Appendix A — GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

User note:

About this resource: In the process of repair and alteration of existing buildings, based on the nature and the extent of the work, this code might require certain upgrades in the fire-resistance rating of building elements, at which time it becomes critical for the designers and the code officials to be able to determine the fire-resistance rating of the existing building elements as part of the overall evaluation for the assessment of the need for improvements. This resource document provides a guideline for such an evaluation for fire-resistance rating of archaic materials that is not typically found in the modern model building codes.

INTRODUCTION

The International Existing Building Code ® (IEBC®) is a comprehensive code with the goal of addressing all aspects of work taking place in existing buildings and providing user-friendly methods and tools for regulation and improvement of such buildings. This resource document is included within the cover of the IEBC with that goal in mind and as a step towards accomplishing that goal.

In the process of repair and alteration of existing buildings, based on the nature and the extent of the work, the IEBC might require certain upgrades in the fire-resistance rating of building elements, at which time it becomes critical for the designers and the code officials to be able to determine the fire-resistance rating of the existing building elements as part of the overall evaluation for the assessment of the need for improvements. This resource document provides a guideline for such an evaluation for fire-resistance ratings of archaic materials that are not typically found in the modern model building codes.

Resource A is only a guideline and is not intended to be a document for specific adoption as it is not written in the format or language of ICC’s International Codes and is not subject to the code development process.

PURPOSE

The Guidelines on Fire Ratings of Archaic Materials and Assemblies focuses upon the fire-related performance of archaic construction. “Archaic” encompasses construction typical of an earlier time, generally prior to 1950. “Fire-related performance” includes fire resistance, flame spread, smoke production and degree of combustibility.

The purpose of this guideline is to update the information which was available at the time of original construction, for use by architects, engineers and code officials when evaluating the fire safety of a rehabilitation project. In addition, information relevant to the evaluation of general classes of materials and types of construction is presented for those cases when documentation of the fire performance of a particular archaic material or assembly cannot be found.

lable at the time of original construction, for use by architects, engineers and code officials when evaluating the fire safety of a rehabilitation project. In addition, information relevant to the evaluation of general classes of materials and types of construction is presented for those cases when documentation of the fire performance of a particular archaic material or assembly cannot be found.

It has been assumed that the building materials and their fastening, joining and incorporation into the building structure are sound mechanically. Therefore, some determination must be made that the original manufacture, the original construction practice and the rigors of aging and use have not weakened the building. This assessment can often be difficult because process and quality control was not good in many industries, and variations among locally available raw materials and manufacturing techniques often resulted in a product which varied widely in its strength and durability. The properties of iron and steel, for example, varied widely, depending on the mill and the process used.

There is nothing inherently inferior about archaic materials or construction techniques. The pressures that promote fundamental change are most often economic or technological matters not necessarily related to concerns for safety. The high cost of labor made wood lath and plaster uneconomical. The high cost of land and the congestion of the cities provided the impetus for high-rise construction. Improved technology made it possible. The difficulty with archaic materials is not a question of suitability, but familiarity.

Code requirements for the fire performance of key building elements (e.g., walls, floor/ceiling assemblies, doors, shaft enclosures) are stated in performance terms: hours of fire resistance. It matters not whether these elements were built in 1908 or 1980, only that they provide the required degree of fire resistance. The level of performance will be defined by the local community, primarily through the enactment of a building or rehabilitation code. This guideline is only a tool to help evaluate the various building elements, regardless of what the level of performance is required to be.

The problem with archaic materials is simply that documentation of their fire performance is not readily available. The application of engineering judgment is more difficult because building officials may not be familiar with the materials or construction method involved. As a result, either a full-scale fire test is required or the archaic construction in question removed and replaced. Both alternatives are time consuming and wasteful.

This guideline and the accompanying appendix are designed to help fill this information void. By providing the necessary documentation, there will be a firm basis for the continued acceptance of archaic materials and assemblies.

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1—FIRE-RELATED PERFORMANCE OF ARCHAIC MATERIALS AND ASSEMBLIES

1.1 FIRE PERFORMANCE MEASURES

This guideline does not specify the level of performance required for the various building components. These requirements are controlled by the building occupancy and use and are set forth in the local building or rehabilitation code.

The fire resistance of a given building element is established by subjecting a sample of the assembly to a “standard” fire test which follows a “standard” time-temperature curve. This test method has changed little since the 1920s. The test results tabulated in the Appendix have been adjusted to reflect current test methods.

The current model building codes cite other fire-related properties not always tested for in earlier years: flame spread, smoke production and degree of combustibility. However, they can generally be assumed to fall within well-defined values because the principal combustible component of archaic materials is cellulose. Smoke production is more important today because of the increased use of plastics. However, the early flame spread tests, developed in the early 1940s, also included a test for smoke production.

“Plastics,” one of the most important classes of contemporary materials, were not found in the review of archaic materials. If plastics are to be used in a rehabilitated building, they should be evaluated by contemporary standards. Information and documentation of their fire-related properties and performance is widely available.

Flame spread, smoke production and degree of combustibility are discussed in detail below. Test results for eight common species of lumber, published in an Underwriter’s Laboratories’ (UL) report (104), are noted in the following table:

TABLE 1.1
TUNNEL TEST RESULTS FOR EIGHT SPECIES OF LUMBER

Flame Spread

The flame spread of interior finishes is most often measured by the ASTM E84 “tunnel test.” This test measures how far and how fast the flames spread across the surface of the test sample. The resulting flame spread rating (FSR) is expressed as a number on a continuous scale where cement-asbestos board is 0 and red oak is 100. (Materials with a flame spread greater than red oak have an FSR greater than 100.) The scale is divided into distinct groups or classes. The most commonly used flame spread classifications are:

– – – Class I or A, with a 0 25 FSR; Class II or B, with a 26 75 FSR; and Class III or C, with a 76 200 FSR. (Note: Some codes use Roman

– numerals and others use letters.) The NFPA Life Safety Code also has a Class D (201 500 FSR) and Class E (over 500 FSR) interior finish.

These classifications are typically used in modern building codes to restrict the rate of fire spread. Only the first three classifications are normally permitted, though not all classes of materials can be used in all places throughout a building. For example, the interior finish of building materials used in exits or in corridors leading to exits is more strictly regulated than materials used within private dwelling units.

In general, inorganic archaic materials (e.g., bricks or tile) can be expected to be in Class I. Materials of whole wood are mostly Class II. Whole wood is defined as wood used in the same form as sawn from the tree. This is in contrast to the contemporary reconstituted wood products such as plywood, fiberboard, hardboard or particle board. If the organic archaic material is not whole wood, the flame spread classification could be well over 200 and thus would be particularly unsuited for use in exits and other critical locations in a building. Some plywoods and various wood fiberboards have flame spreads over 200. Although they can be treated with fire retardants to reduce their flame spread, it would be advisable to assume that all such products have a flame spread over 200 unless there is information to the contrary.

Smoke Production

The evaluation of smoke density is part of the ASTM E84 tunnel test. For the eight species of lumber shown in Table 1.1, the highest levels are 275–305 for Yellow Pine, but most of the others are less smoky than red oak which has an index of 100. The advent of plastics caused substantial increases in the smoke density values measured by the tunnel test. The ensuing limitation of the smoke production for wall and ceiling materials by the model building codes has been a reaction to the introduction of plastic materials. In general, cellulosic materials fall in the 50–300 range of smoke density which is below the general limitation of 450 adopted by many codes.

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Degree of Combustibility

The model building codes tend to define “noncombustibility” on the basis of having passed ASTM E136 or if the material is totally inorganic. The acceptance of gypsum wallboard as noncombustible is based on limiting paper thickness to not over [1] / 8 inch and a 0– 50 flame spread rating by ASTM E84. At times there were provisions to define a Class I or A material (0–25 FSR) as noncombustible, but this is not currently recognized by most model building codes.

If there is any doubt whether or not an archaic material is noncombustible, it would be appropriate to send out samples for evaluation. If an archaic material is determined to be noncombustible according to ASTM E136, it can be expected that it will not contribute fuel to the fire.

1.2 COMBUSTIBLE CONSTRUCTION TYPES

One of the earliest forms of timber construction used exterior load-bearing masonry walls with columns and/or wooden walls supporting wooden beams and floors in the interior of the building. This form of construction, often called “mill” or “heavy timber” construction, has approximately 1-hour fire resistance. The exterior walls will generally contain the fire within the building.

With the development of dimensional lumber, there was a switch from heavy timber to “balloon frame” construction. The balloon frame uses load-bearing exterior wooden walls which have long timbers often extending from foundation to roof. When longer lumber became scarce, another form of construction, “platform” framing, replaced the balloon framing. The difference between the two systems is significant because platform framing is automatically fire-blocked at every floor while balloon framing commonly has concealed spaces that extend unblocked from basement to attic. The architect, engineer and code official must be alert to the details of construction and the ease with which fire can spread in concealed spaces.

2—BUILDING EVALUATION

A given rehabilitation project will most likely go through several stages. The preliminary evaluation process involves the designer in surveying the prospective building. The fire resistance of existing building materials and construction systems is identified; potential problems are noted for closer study. The final evaluation phase includes: developing design solutions to upgrade the fire resistance of building elements, if necessary; preparing working drawings and specifications; and the securing of the necessary code approvals.

2.1 PRELIMINARY EVALUATION

A preliminary evaluation should begin with a building survey to determine the existing materials, the general arrangement of the structure and the use of the occupied spaces, and the details of construction. The designer needs to know “what is there” before a decision can be reached about what to keep and what to remove during the rehabilitation process. This preliminary evaluation should be as detailed as necessary to make initial plans. The fire-related properties need to be determined from the applicable building or rehabilitation code, and the materials and assemblies existing in the building then need to be evaluated for these properties. Two worksheets are shown below to facilitate the preliminary evaluation.

ring the rehabilitation process. This preliminary evaluation should be as detailed as necessary to make initial plans. The fire-related properties need to be determined from the applicable building or rehabilitation code, and the materials and assemblies existing in the building then need to be evaluated for these properties. Two worksheets are shown below to facilitate the preliminary evaluation.

Two possible sources of information helpful in the preliminary evaluation are the original building plans and the building code in effect at the time of original construction. Plans may be on file with the local building department or in the offices of the original designers (e.g., architect, engineer) or their successors. If plans are available, the investigator should verify that the building was actually constructed as called for in the plans, as well as incorporate any later alterations or changes to the building. Earlier editions of the local building code should be on file with the building official. The code in effect at the time of construction will contain fire performance criteria. While this is no guarantee that the required performance was actually provided, it does give the investigator some guidance as to the level of performance which may be expected. Under some code administration and enforcement systems, the code in effect at the time of construction also defines the level of performance that must be provided at the time of rehabilitation.

Table 2.1(1) illustrates one method for organizing preliminary field notes. Space is provided for the materials, dimensions and condition of the principal building elements. Each floor of the structure should be visited and the appropriate information obtained. In practice, there will often be identical materials and construction on every floor, but the exception may be of vital importance. A schematic diagram should be prepared of each floor showing the layout of exits and hallways and indicating where each element described in the field notes fits into the structure as a whole. The exact arrangement of interior walls within apartments is of secondary importance from a fire safety point of view and need not be shown on the drawings unless these walls are required by code to have a fire-resistance rating.

The location of stairways and elevators should be clearly marked on the drawings. All exterior means of escape (e.g., fire escapes) should be identified. (Note: Problems providing adequate exiting are discussed at length in the Egress Guideline for Residential Rehabilitation .)

The following notes explain the entries in Table 2.1(1).

Exterior Bearing Walls. Many old buildings utilize heavily constructed walls to support the floor/ceiling assemblies at the exterior of the building. There may be columns and/or interior bearing walls within the structure, but the exterior walls are an important factor in assessing the fire safety of a building.

The field investigator should note how the floor/ceiling assemblies are supported at the exterior of the building. If columns are incorporated in the exterior walls, the walls may be considered nonbearing.

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Interior Bearing Walls. It may be difficult to determine whether or not an interior wall is load bearing, but the field investigator should attempt to make this determination. At a later stage of the rehabilitation process, this question will need to be determined exactly. Therefore, the field notes should be as accurate as possible.

Exterior Nonbearing Walls. The fire resistance of the exterior walls is important for two reasons. These walls (both bearing and nonbearing) are depended upon to: a) contain a fire within the building of origin; or b) keep an exterior fire outside the building. It is therefore important to indicate on the drawings where any openings are located as well as the materials and construction of all doors or shutters. The drawings should indicate the presence of wired glass, its thickness and framing, and identify the materials used for windows and door frames. The protection of openings adjacent to exterior means of escape (e.g., exterior stairways, fire escapes) is particularly important. The ground floor drawing should locate the building on the property and indicate the precise distances to adjacent buildings.

Interior Nonbearing Walls (Partitions). A partition is a “wall that extends from floor to ceiling and subdivides space within any story of a building” (see Bibliography entry 35). Table 2.1(1) has two categories (A & B) for Interior Nonbearing Walls (Partitions) which can be used for different walls, such as hallway walls as compared to inter-apartment walls. Under some circumstances there may be only one type of wall construction; in others, three or more types of wall construction may occur.

The field investigator should be alert for differences in function as well as in materials and construction details. In general, the details within apartments are not as important as the major exit paths and exit stairways. The preliminary field investigation should attempt to determine the thickness of all walls. A term introduced below called “thickness design” will depend on an accurate (± [1] / 4 inch) determination. Even though this initial field survey is called “preliminary,” the data generated should be as accurate and complete as possible.

The field investigator should note the exact location from which observations are recorded. For instance, if a hole is found through a wall enclosing an exit stairway which allows a cataloguing of the construction details, the field investigation notes should reflect the location of the “find.” At the preliminary stage it is not necessary to core every wall; the interior details of construction can usually be determined at some location.

act location from which observations are recorded. For instance, if a hole is found through a wall enclosing an exit stairway which allows a cataloguing of the construction details, the field investigation notes should reflect the location of the “find.” At the preliminary stage it is not necessary to core every wall; the interior details of construction can usually be determined at some location.

Structural Frame. There may or may not be a complete skeletal frame, but usually there are columns, beams, trusses or other like elements. The dimensions and spacing of the structural elements should be measured and indicated on the drawings. For instance, if there are 10-inch-square columns located on a 30-foot-square grid throughout the building, this should be noted. The structural material and cover or protective materials should be identified wherever possible. The thickness of the cover materials should be determined to an accuracy of ± [1] / 4 inch. As discussed above, the preliminary field survey usually relies on accidental openings in the cover materials rather than a systematic coring technique.

Floor/Ceiling Structural Systems. The span between supports should be measured. If possible, a sketch of the cross-section of the system should be made. If there is no location where accidental damage has opened the floor/ceiling construction to visual inspection, it is necessary to make such an opening. An evaluation of the fire resistance of a floor/ceiling assembly requires detailed knowledge of the materials and their arrangement. Special attention should be paid to the cover on structural steel elements and the condition of suspended ceilings and similar membranes.

Roofs. The preliminary field survey of the roof system is initially concerned with watertightness. However, once it is apparent that the roof is sound for ordinary use and can be retained in the rehabilitated building, it becomes necessary to evaluate the fire performance. The field investigator must measure the thickness and identify the types of materials which have been used. Be aware that there may be several layers of roof materials.

Doors. Doors to stairways and hallways represent some of the most important fire elements to be considered within a building. The uses of the spaces separated largely controls the level of fire performance necessary. Walls and doors enclosing stairways or elevator shafts would normally require a higher level of performance than between the bedroom and bath. The various uses are differentiated in Table 2.1(1).

Careful measurements of the thickness of door panels must be made, and the type of core material within each door must be determined. It should be noted whether doors have self-closing devices; the general operation of the doors should be checked. The latch should engage and the door should fit tightly in the frame. The hinges should be in good condition. If glass is used in the doors, it should be identified as either plain glass or wired glass mounted in either a wood or steel frame.

terial within each door must be determined. It should be noted whether doors have self-closing devices; the general operation of the doors should be checked. The latch should engage and the door should fit tightly in the frame. The hinges should be in good condition. If glass is used in the doors, it should be identified as either plain glass or wired glass mounted in either a wood or steel frame.

Materials. The field investigator should be able to identify ordinary building materials. In situations where an unfamiliar material is found, a sample should be obtained. This sample should measure at least 10 cubic inches so that an ASTM E136 fire test can be conducted to determine if it is combustible.

Thickness. The thickness of all materials should be measured accurately since, under certain circumstances, the level of fire resistance is very sensitive to the material thickness.

Condition. The method of attaching the various layers and facings to one another or to the supporting structural element should be noted under the appropriate building element. The “secureness” of the attachment and the general condition of the layers and facings should be noted here.

Notes. The “Notes” column can be used for many purposes, but it might be a good idea to make specific references to other field notes or drawings.

After the building survey is completed, the data collected must be analyzed. A suggested work sheet for organizing this information is given as Table 2.1(2).

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TABLE 2.1(1)
PRELIMINARY EVALUATION FIELD NOTES

The required fire resistance and flame spread for each building element are normally established by the local building or rehabilitation code. The fire performance of the existing materials and assemblies should then be estimated, using one of the techniques described below. If the fire performance of the existing building element(s) is equal to or greater than that required, the materials and assemblies may remain. If the fire performance is less than required, then corrective measures must be taken.

cal building or rehabilitation code. The fire performance of the existing materials and assemblies should then be estimated, using one of the techniques described below. If the fire performance of the existing building element(s) is equal to or greater than that required, the materials and assemblies may remain. If the fire performance is less than required, then corrective measures must be taken.

The most common methods of upgrading the level of protection are to either remove and replace the existing building element(s) or to repair and upgrade the existing materials and assemblies. Other fire protection measures, such as automatic sprinklers or detection and alarm systems, also could be considered, though they are beyond the scope of this guideline. If the upgraded protection is still less than that required or deemed to be acceptable, additional corrective measures must be taken. This process must continue until an acceptable level of performance is obtained. TABLE 2.1(2) PRELIMINARY EVALUATION WORKSHEET

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2.2 FIRE RESISTANCE OF EXISTING BUILDING ELEMENTS

The fire resistance of the existing building elements can be estimated from the tables and histograms contained in the Appendix. The Appendix is organized first by type of building element: walls, columns, floor/ceiling assemblies, beams and doors. Within each building element, the tables are organized by type of construction (e.g., masonry, metal, wood frame) and then further divided by minimum dimensions or thickness of the building element.

A histogram precedes every table that has 10 or more entries. The X-axis measures fire resistance in hours; the Y-axis shows the number of entries in that table having a given level of fire resistance. The histograms also contain the location of each entry within that table for easy cross-referencing.

The histograms, because they are keyed to the tables, can speed the preliminary investigation. For example, Table 1.3.2, Wood Frame Walls 4" to Less Than 6" Thick, contains 96 entries. Rather than study each table entry, the histogram shows that every wall assembly listed in that table has a fire resistance of less than 2 hours. If the building code required the wall to have 2-hour fire resistance, the designer, with a minimum of effort, is made aware of a problem that requires closer study.

Suppose the code had only required a wall of 1-hour fire resistance. The histogram shows far fewer complying elements (19) than noncomplying ones (77). If the existing assembly is not one of the 19 complying entries, there is a strong possibility the existing assembly is deficient. The histograms can also be used in the converse situation. If the existing assembly is not one of the smaller number of entries with a lower than required fire resistance, there is a strong possibility the existing assembly will be acceptable.

At some point, the existing building component or assembly must be located within the tables. Otherwise, the fire resistance must be determined through one of the other techniques presented in the guideline. Locating the building component in the Appendix tables not only guarantees the accuracy of the fire-resistance rating, but also provides a source of documentation for the building official.

2.3 EFFECTS OF PENETRATIONS IN FIRE-RESISTANT ASSEMBLIES

There are often many features in existing walls or floor/ceiling assemblies which were not included in the original certification or fire testing. The most common examples are pipes and utility wires passed through holes poked through an assembly. During the life of the building, many penetrations are added, and by the time a building is ready for rehabilitation, it is not sufficient to just consider the fire resistance of the assembly as originally constructed. It is necessary to consider all penetrations and their relative impact upon fire performance. For instance, the fire resistance of the corridor wall may be less important than the effect of plain glass doors or transoms. In fact, doors are the most important single class of penetrations.

A fully developed fire generates substantial quantities of heat and excess gaseous fuel capable of penetrating any holes which might be present in the walls or ceiling of the fire compartment. In general, this leads to a severe degradation of the fire resistance of those building elements and to a greater potential for fire spread. This is particularly applicable to penetrations located high in a compartment where the positive pressure of the fire can force the unburned gases through the penetration.

ating any holes which might be present in the walls or ceiling of the fire compartment. In general, this leads to a severe degradation of the fire resistance of those building elements and to a greater potential for fire spread. This is particularly applicable to penetrations located high in a compartment where the positive pressure of the fire can force the unburned gases through the penetration.

Penetrations in a floor/ceiling assembly will generally completely negate the barrier qualities of the assembly and will lead to rapid spread of fire to the space above. It will not be a problem, however, if the penetrations are filled with noncombustible materials strongly fastened to the structure. The upper half of walls are similar to the floor/ceiling assembly in that a positive pressure can reasonably be expected in the top of the room, and this will push hot and/or burning gases through the penetration unless it is completely sealed.

Building codes require doors installed in fire-resistive walls to resist the passage of fire for a specified period of time. If the door to a fully involved room is not closed, a large plume of fire will typically escape through the doorway, preventing anyone from using the space outside the door while allowing the fire to spread. This is why door closers are so important. Glass in doors and transoms can be expected to rapidly shatter unless constructed of listed or approved wire glass in a steel frame. As with other building elements, penetrations or nonrated portions of doors and transoms must be upgraded or otherwise protected.

Table 5.1 in Section V of the Appendix contains 41 entries of doors mounted in sound tight-fitting frames. Section 3.4 below outlines one procedure for evaluating and possibly upgrading existing doors.

3—FINAL EVALUATION AND DESIGN SOLUTION

The final evaluation begins after the rehabilitation project has reached the final design stage and the choice is made to keep certain archaic materials and assemblies in the rehabilitated building. The final evaluation process is essentially a more refined and detailed version of the preliminary evaluation. The specific fire-resistance and flame-spread requirements are determined for the project. This may involve local building and fire officials reviewing the preliminary evaluation as depicted in Tables 2.1(1) and 2.1(2) and the field drawings and notes. When necessary, provisions must be made to upgrade existing building elements to provide the required level of fire performance.

There are several approaches to design solutions that can make possible the continued use of archaic materials and assemblies in the rehabilitated structure. The simplest case occurs when the materials and assembly in question are found within the Appendix tables and the fire performance properties satisfy code requirements. Other approaches must be used, though, if the assembly cannot be found within the Appendix or the fire performance needs to be upgraded. These approaches have been grouped into two classes: experimental and theoretical.

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3.1 THE EXPERIMENTAL APPROACH

If a material or assembly found in a building is not listed in the Appendix tables, there are several other ways to evaluate fire performance. One approach is to conduct the appropriate fire test(s) and thereby determine the fire-related properties directly. There are a number of laboratories in the United States which routinely conduct the various fire tests.

The contract with any of these testing laboratories should require their observation of specimen preparation as well as the testing of the specimen. A complete description of where and how the specimen was obtained from the building, the transportation of the specimen, and its preparation for testing should be noted in detail so that the building official can be satisfied that the fire test is representative of the actual use.

The test report should describe the fire test procedure and the response of the material or assembly. The laboratory usually submits a cover letter with the report to describe the provisions of the fire test that were satisfied by the material or assembly under investigation. A building official will generally require this cover letter but will also read the report to confirm that the material or assembly complies with the code requirements. Local code officials should be involved in all phases of the testing process.

The experimental approach can be costly and time consuming because specimens must be taken from the building and transported to the testing laboratory. When a load-bearing assembly has continuous reinforcement, the test specimen must be removed from the building, transported and tested in one piece. However, when the fire performance cannot be determined by other means, there may be no alternative to a full-scale test. A “nonstandard” small-scale test can be used in special cases. Sample sizes need only be 10–25 square feet (0.93–2.3 m [2] ), while full-scale tests require test samples of either 100 or 180 square feet (9.3 or 17 m [2] ) in size. This small-scale test is best suited for testing nonload-bearing assemblies against thermal transmission only.

3.2 THE THEORETICAL APPROACH

There will be instances when materials and assemblies in a building undergoing rehabilitation cannot be found in the Appendix tables. Even where test results are available for more or less similar construction, the proper classification may not be immediately apparent. Variations in dimensions, loading conditions, materials or workmanship may markedly affect the performance of the individual building elements, and the extent of such a possible effect cannot be evaluated from the tables.

on cannot be found in the Appendix tables. Even where test results are available for more or less similar construction, the proper classification may not be immediately apparent. Variations in dimensions, loading conditions, materials or workmanship may markedly affect the performance of the individual building elements, and the extent of such a possible effect cannot be evaluated from the tables.

Theoretical methods being developed offer an alternative to the full-scale fire tests discussed above. For example, Section 4302(b) of the 1979 edition of the Uniform Building Code specifically allows an engineering design for fire resistance in lieu of conducting full-scale tests. These techniques draw upon computer simulation and mathematical modeling, thermodynamics, heatflow analysis and materials science to predict the fire performance of building materials and assemblies.

One theoretical method, known as the “Ten Rules of Fire Endurance Ratings,” was published by T. Z. Harmathy in the May, 1965 edition of Fire Technology (see Bibliography entry 35). Harmathy’s Rules provide a foundation for extending the data within the Appendix tables to analyze or upgrade current as well as archaic building materials or assemblies.

HARMATHY'S TEN RULES

Rule 1: The “thermal” fire endurance of a construction consisting of a number of parallel layers is greater than the sum of the “thermal” fire endurances characteristic of the individual layers when exposed separately to fire. (Note: The “thermal” fire endurance is the time at which the average temperature on the unexposed side of a construction exceeds its initial value by 250°F (121°C) when the other side is exposed to the “standard” fire specified by ASTM Test Method E-19.)

The minimum performance of an untested assembly can be estimated if the fire endurance of the individual components is known. Though the exact rating of the assembly cannot be stated, the endurance of the assembly is greater than the sum of the endurance of the components.

When a building assembly or component is found to be deficient, the fire endurance can be upgraded by providing a protective membrane. This membrane could be a new layer of brick, plaster or drywall. The fire endurance of this membrane is called the “finish rating.” Appendix tables 1.5.1 and 1.5.2 contain the finish ratings for the most commonly employed materials. (See also the notes to Rule 2.)

The test criteria for the finish rating is the same as for the thermal fire endurance of the total assembly: average temperature increases of 250°F (121°C) above ambient or 325°F (163°C) above ambient at any one place with the membrane being exposed to the fire. The temperature is measured at the interface of the assembly and the protective membrane.

Rule 2: The fire endurance of a construction does not decrease with the addition of further layers.

Harmathy notes that this rule is a consequence of the previous rule. Its validity follows from the fact that the additional layers increase both the resistance to heat flow and the heat capacity of the construction. This, in turn, reduces the rate of temperature rise at the unexposed surface.

This rule is not just restricted to “thermal” performance but affects the other fire test criteria: direct flame passage, cotton waste ignition and load bearing performance. This means that certain restrictions must be imposed on the materials to be added and on the loading conditions. One restriction is that a new layer, if applied to the exposed surface, must not produce additional thermal stresses in the construction, i.e., its thermal expansion characteristics must be similar to those of the adjacent layer. Each new layer must also be capable of contributing enough additional strength to the assembly to sustain the added dead load. If this requirement is not fulfilled, the allowable live load must be reduced by an amount equal to the weight of the new layer. Because of these limitations, this rule should not be applied without careful consideration.

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Particular care must be taken if the material added is a good thermal insulator. Properly located, the added insulation could improve the “thermal” performance of the assembly. Improperly located, the insulation could block necessary thermal transmission through the assembly, thereby subjecting the structural elements to greater temperatures for longer periods of time, and could cause premature structural failure of the supporting members.

Rule 3: The fire endurance of constructions containing continuous air gaps or cavities is greater than the fire endurance of similar constructions of the same weight, but containing no air gaps or cavities.

By providing for voids in a construction, additional resistances are produced in the path of heat flow. Numerical heat flow analyses indicate that a 10 to 15 percent increase in fire endurance can be achieved by creating an air gap at the midplane of a brick wall. Since the gross volume is also increased by the presence of voids, the air gaps and cavities have a beneficial effect on stability as well. However, constructions containing combustible materials within an air gap may be regarded as exceptions to this rule because of the possible development of burning in the gap.

There are numerous examples of this rule in the tables. For instance:

Table 1.1.4; Item W-8-M-82: Cored concrete masonry, nominal 8 inch thick wall with one unit in wall thickness and with 62 percent minimum of solid material in each unit, load bearing (80 PSI). Fire endurance: 2 [1] / 2 hours.

Table 1.1.5; Item W-10-M-11: Cored concrete masonry, nominal 10 inch thick wall with two units in wall thickness and a 2-inch (51 mm) air space, load bearing (80 PSI). The units are essentially the same as item W-8-M-82. Fire endurance: 3 [1] / 2 hours.

These walls show 1 hour greater fire endurance by the addition of the 2-inch (51 mm) air space.

Rule 4: The farther an air gap or cavity is located from the exposed surface, the more beneficial is its effect on the fire endurance.

Radiation dominates the heat transfer across an air gap or cavity, and it is markedly higher where the temperature is higher.

The air gap or cavity is thus a poor insulator if it is located in a region which attains high temperatures during fire exposure.

Some of the clay tile designs take advantage of these factors. The double cell design, for instance, ensures that there is a cavity near the unexposed face. Some floor/ceiling assemblies have air gaps or cavities near the top surface and these enhance their thermal performance.

Rule 5: The fire endurance of a construction cannot be increased by increasing the thickness of a completely enclosed air layer. Harmathy notes that there is evidence that if the thickness of the air layer is larger than about [1] / 2 inch (12.7 mm), the heat transfer through the air layer depends only on the temperature of the bounding surfaces, and is practically independent of the distance between them. This rule is not applicable if the air layer is not completely enclosed, i.e., if there is a possibility of fresh air entering the gap at an appreciable rate.

Rule 6: Layers of materials of low thermal conductivity are better utilized on that side of the construction on which fire is more likely to happen.

As in Rule 4, the reason lies in the heat transfer process, though the conductivity of the solid is much less dependent on the ambient temperature of the materials. The low thermal conductor creates a substantial temperature differential to be established across its thickness under transient heat flow conditions. This rule may not be applicable to materials undergoing physical-chemical changes accompanied by significant heat absorption or heat evolution.

Rule 7: The fire endurance of asymmetrical constructions depends on the direction of heat flow.

This rule is a consequence of Rules 4 and 6, as well as other factors. This rule is useful in determining the relative protection of corridors and walls enclosing an exit stairway from the surrounding spaces. In addition, there are often situations where a fire is more likely, or potentially more severe, from one side or the other.

Rule 8: The presence of moisture, if it does not result in explosive spalling, increases the fire endurance.

The flow of heat into an assembly is greatly hindered by the release and evaporation of the moisture found within cementitious materials such as gypsum, Portland cement or magnesium oxychloride. Harmathy has shown that the gain in fire endurance may be as high as 8 percent for each percent (by volume) of moisture in the construction. It is the moisture chemically bound within the construction material at the time of manufacture or processing that leads to increased fire endurance. There is no direct relationship between the relative humidity of the air in the pores of the material and the increase in fire endurance.

Under certain conditions there may be explosive spalling of low permeability cementitious materials such as dense concrete. In general, one can assume that extremely old concrete has developed enough minor cracking that this factor should not be significant.

Rule 9: Load-supporting elements, such as beams, girders and joists, yield higher fire endurances when subjected to fire endurance tests as parts of floor, roof or ceiling assemblies than they would when tested separately.

One of the fire endurance test criteria is the ability of a load-supporting element to carry its design load. The element will be deemed to have failed when the load can no longer be supported.

Failure usually results for two reasons. Some materials, particularly steel and other metals, lose much of their structural strength at elevated temperatures. Physical deflection of the supporting element, due to decreased strength or thermal expansion, causes a redistribution of the load forces and stresses throughout the element. Structural failure often results because the supporting element is not designed to carry the redistributed load.

Roof, floor and ceiling assemblies have primary (e.g., beams) and secondary (e.g., floor joists) structural members. Since the primary load-supporting elements span the largest distances, their deflection becomes significant at a stage when the strength of the secondary members (including the roof or floor surface) is hardly affected by the heat. As the secondary members follow the

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deflection of the primary load-supporting element, an increasingly larger portion of the load is transferred to the secondary members.

When load-supporting elements are tested separately, the imposed load is constant and equal to the design load throughout the test. By definition, no distribution of the load is possible because the element is being tested by itself. Without any other structural members to which the load could be transferred, the individual elements cannot yield a higher fire endurance than they do when tested as parts of a floor, roof or ceiling assembly.

Rule 10: The load-supporting elements (beams, girders, joists, etc.) of a floor, roof or ceiling assembly can be replaced by such other load-supporting elements which, when tested separately, yielded fire endurances not less than that of the assembly.

This rule depends on Rule 9 for its validity. A beam or girder, if capable of yielding a certain performance when tested separately, will yield an equally good or better performance when it forms a part of a floor, roof or ceiling assembly. It must be emphasized that the supporting element of one assembly must not be replaced by the supporting element of another assembly if the performance of this latter element is not known from a separate (beam) test. Because of the load-reducing effect of the secondary elements that results from a test performed on an assembly, the performance of the supporting element alone cannot be evaluated by simple arithmetic. This rule also indicates the advantage of performing separate fire tests on primary load-supporting elements.

ILLUSTRATION OF HARMATHY’S RULES

Harmathy provided one schematic figure which illustrated his rules. It should be useful as a quick reference to assist in applying his rules.

FIGURE 3.2—DIAGRAMMATIC ILLUSTRATION OF HARMATHY’S TEN RULES [a]

IRE

t = Fire endurance

a. Reproduced from the May 1965 Fire Technology (Vol. 1, No. 2). Copyright National Fire Protection Association, Boston. Reproduced by permission.

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EXAMPLE APPLICATION OF HARMATHY’S RULES

The following examples, based in whole or in part upon those presented in Harmathy’s paper (see Bibliography entry 35), show how the rules can be applied to practical cases.

Example 1 :

Problem

A contractor would like to keep a partition which consists of a 3 [3] / 4 inch (95 mm) thick layer of red clay brick, a 1 [1] / 4 inch (32 mm) thick layer of plywood and a [3] / 8 inch (9.5 mm) thick layer of gypsum wallboard at a location where 2-hour fire endurance is required. Is this assembly capable of providing a 2-hour protection?

Solution

(1) This partition does not appear in the Appendix tables. (2) Bricks of this thickness yield fire endurances of approximately 75 minutes (Table 1.1.2, Item W-4-M-2). (3) The 1 [1] / 4 inch (32 mm) thick plywood has a finish rating of 30 minutes. (4) The [3] / 8 inch (9.5 mm) gypsum wallboard has a finish rating of 10 minutes. (5) Using the recommended values from the tables and applying Rule 1, the fire endurance (FI) of the assembly is larger than the sum of the individual layers, or FI > 75 + 30 + 10 = 115 minutes

Discussion

This example illustrates how the Appendix tables can be utilized to determine the fire resistance of assemblies not explicitly listed.

Example 2 :

Problem

(1) A number of buildings to be rehabilitated have the same type of roof slab which is supported with different structural elements.

(2) The designer and contractor would like to determine whether or not this roof slab is capable of yielding a 2-hour fire endurance. According to a rigorous interpretation of ASTM E119, however, only the roof assembly, including the roof slab as well as the cover and the supporting elements, can be subjected to a fire test. Therefore, a fire endurance classification cannot be issued for the slabs separately. (3) The designer and contractor believe this slab will yield a 2-hour fire endurance even without the cover, and any beam of at least 2-hour fire endurance will provide satisfactory support. Is it possible to obtain a classification for the slab separately?

Solution

(1) The answer to the question is yes. (2) According to Rule 10, it is not contrary to common sense to test and classify roofs and supporting elements separately. Furthermore, according to Rule 2, if the roof slabs actually yield a 2-hour fire endurance, the endurance of an assembly, including the slabs, cannot be less than 2 hours. (3) The recommended procedure would be to review the tables to see if the slab appears as part of any tested roof or floor/ceiling assembly. The supporting system can be regarded as separate from the slab specimen, and the fire endurance of the assembly listed in the table is at least the fire endurance of the slab. There would have to be an adjustment for the weight of the roof cover in the allowable load if the test specimen did not contain a cover. (4) The supporting structure or element would have to have at least a 2-hour fire endurance when tested separately.

Discussion

If the tables did not include tests on assemblies which contained the slab, one procedure would be to assemble the roof slabs on any convenient supporting system (not regarded as part of the specimen) and to subject them to a load which, besides the usually required superimposed load, includes some allowances for the weight of the cover.

Example 3 :

Problem

A steel-joisted floor and ceiling assembly is known to have yielded a fire endurance of 1 hour and 35 minutes. At a certain location, a 2-hour endurance is required. What is the most economical way of increasing the fire endurance by at least 25 minutes?

Solution

(1) The most effective technique would be to increase the ceiling plaster thickness. Existing coats of paint would have to be removed and the surface properly prepared before the new plaster could be applied. Other materials (e.g., gypsum wallboard) could also be considered. (2) There may be other techniques based on other principles, but an examination of the drawings would be necessary.

Discussion

(1) The additional plaster has at least three effects: a) The layer of plaster is increased and thus there is a gain of fire endurance (Rule 1).

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b) There is a gain due to shifting the air gap farther from the exposed surface (Rule 4). c) There is more moisture in the path of heat flow to the structural elements (Rules 7 and 8). (2) The increase in fire endurance would be at least as large as that of the finish rating for the added thickness of plaster. The combined effects in (1) above would further increase this by a factor of 2 or more, depending upon the geometry of the assembly.

Example 4:

Problem

The fire endurance of item W-10-M-l in Table 1.1.5 is 4 hours. This wall consists of two 3 [3] / 4 inch (95 mm) thick layers of structural tiles separated by a 2-inch (51 mm) air gap and [3] / 4 inch (19 mm) Portland cement plaster or stucco on both sides. If the actual wall in the building is identical to item W-10-M-1 except that it has a 4-inch (102 mm) air gap, can the fire endurance be estimated at 5 hours?

nce of item W-10-M-l in Table 1.1.5 is 4 hours. This wall consists of two 3 [3] / 4 inch (95 mm) thick layers of structural tiles separated by a 2-inch (51 mm) air gap and [3] / 4 inch (19 mm) Portland cement plaster or stucco on both sides. If the actual wall in the building is identical to item W-10-M-1 except that it has a 4-inch (102 mm) air gap, can the fire endurance be estimated at 5 hours?

Solution

The answer to the question is no for the reasons contained in Rule 5.

Example 5 :

Problem

In order to increase the insulating value of its precast roof slabs, a company has decided to use two layers of different concretes. The lower layer of the slabs, where the strength of the concrete is immaterial (all the tensile load is carried by the steel reinforcement), would be made with a concrete of low strength but good insulating value. The upper layer, where the concrete is supposed to carry the compressive load, would remain the original high strength, high thermal conductivity concrete. How will the fire endurance of the slabs be affected by the change?

Solution

The effect on the thermal fire endurance is beneficial:

(1) The total resistance to heat flow of the new slabs has been increased due to the replacement of a layer of high thermal conductivity by one of low conductivity. (2) The layer of low conductivity is on the side more likely to be exposed to fire, where it is more effectively utilized according to Rule 6. The layer of low thermal conductivity also provides better protection for the steel reinforcement, thereby extending the time before reaching the temperature at which the creep of steel becomes significant.

3.3 “THICKNESS DESIGN” STRATEGY

The “thickness design” strategy is based upon Harmathy’s Rules 1 and 2. This design approach can be used when the construction materials have been identified and measured but the specific assembly cannot be located within the tables. The tables should be surveyed again for thinner walls of like material and construction detail that have yielded the desired or greater fire endurance. If such an assembly can be found, then the thicker walls in the building have more than enough fire resistance. The thickness of the walls thus becomes the principal concern.

This approach can also be used for floor/ceiling assemblies, except that the thickness of the cover and the slab become the central concern. (Note: “Cover” is defined as the protective layer or membrane of material which shows the flow of heat to the structural elements.) The fire resistance of the untested assembly will be at least the fire resistance of an assembly listed in the table having a similar design but with less cover and/or thinner slabs. For other structural elements (e.g., beams and columns), the element listed in the table must also be of a similar design but with less cover thickness.

3.4 EVALUATION OF DOORS

A separate section on doors has been included because the process for evaluation presented below differs from those suggested previously for other building elements. The impact of unprotected openings or penetrations in fire resistant assemblies has been detailed in Section 2.3 above. It is sufficient to note here that openings left unprotected will likely lead to failure of the barrier under actual fire conditions.

For other types of building elements (e.g., beams, columns), the Appendix tables can be used to establish a minimum level of fire performance. The benefit to rehabilitation is that the need for a full-scale fire test is then eliminated. For doors, however, this cannot be done. The data contained in Appendix Table 5.1, Resistance of Doors to Fire Exposure, can only provide guidance as to whether a successful fire test is even feasible.

For example, a door required to have 1 hour fire resistance is noted in the tables as providing only 5 minutes. The likelihood of achieving the required 1 hour, even if the door is upgraded, is remote. The ultimate need for replacement of the doors is reasonably clear, and the expense and time needed for testing can be saved. However, if the performance documented in the table is near or in excess of what is being required, then a fire test should be conducted. The test documentation can then be used as evidence of compliance with the required level of performance.

The table entries cannot be used as the sole proof of performance of the door in question because there are too many unknown variables which could measurably affect fire performance. The wood may have dried over the years; coats of flammable varnish could have been added. Minor deviations in the internal construction of a door can result in significant differences in performance.

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Methods of securing inserts in panel doors can vary. The major nondestructive method of analysis, an X-ray, often cannot provide the necessary detail. It is for these, and similar reasons, that a fire test is still felt to be necessary.

It is often possible to upgrade the fire performance of an existing door. Sometimes, “as is” and modified doors are evaluated in a single series of tests when failure of the unmodified door is expected. Because doors upgraded after an initial failure must be tested again, there is a potential savings of time and money.

The most common problems encountered are plain glass, panel inserts of insufficient thickness and improper fit of a door in its frame. The latter problem can be significant because a fire can develop a substantial positive pressure, and the fire will work its way through otherwise innocent-looking gaps between door and frame.

One approach to solving these problems is as follows. The plain glass is replaced with approved or listed wire glass in a steel frame. The panel inserts can be upgraded by adding an additional layer of material. Gypsum wallboard is often used for this purpose. Intumescent paint applied to the edges of the door and frame will expand when exposed to fire, forming an effective seal around the edges. This seal, coupled with the generally even thermal expansion of a wood door in a wood frame, can prevent the passage of flames and other fire gases. Figure 3.4 illustrates these solutions.

Because the interior construction of a door cannot be determined by a visual inspection, there is no absolute guarantee that the remaining doors are identical to the one(s) removed from the building and tested. But the same is true for doors constructed today, and reason and judgment must be applied. Doors that appear identical upon visual inspection can be weighed. If the weights are reasonably close, the doors can be assumed to be identical and therefore provide the same level of fire performance. Another approach is to fire test more than one door or to dismantle doors selected at random to see if they had been constructed in the same manner. Original building plans showing door details or other records showing that doors were purchased at one time or obtained from a single supplier can also be evidence of similar construction.

More often though, it is what is visible to the eye that is most significant. The investigator should carefully check the condition and fit of the door and frame, and for frames out of plumb or separating from the wall. Door closers, latches and hinges must be examined to see that they function properly and are tightly secured. If these are in order and the door and frame have passed a fullscale test, there can be a reasonable basis for allowing the existing doors to remain.

FIGURE 3.4

MODIFICATION DETAILS

3/ 8"
PLYWOOD

For SI: 1 inch = 25.4 mm.

4—SUMMARY

This section summarizes the various approaches and design solutions discussed in the preceding sections of the guideline. The term “structural system” includes: frames, beams, columns and other structural elements. “Cover” is a protective layer(s) of materials or membrane which slows the flow of heat to the structural elements. It cannot be stressed too strongly that the fire endurance of actual building elements can be greatly reduced or totally negated by removing part of the cover to allow pipes, ducts or conduits to pass through the element. This must be repaired in the rehabilitation process.

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The following approaches shall be considered equivalent.

4.1 The fire resistance of a building element can be established from the Appendix tables. This is subject to the following limitations:

The building element in the rehabilitated building shall be constructed of the same materials with the same nominal dimensions as stated in the tables.

All penetrations in the building element or its cover for services such as electricity, plumbing and HVAC shall be packed with noncombustible cementitious materials and so fixed that the packing material will not fall out when it loses its water of hydration.

The effects of age and wear and tear shall be repaired so that the building element is sound and the original thickness of all components, particularly covers and floor slabs, is maintained.

This approach essentially follows the approach taken by model building codes. The assembly must appear in a table either published in or accepted by the code for a given fire-resistance rating to be recognized and accepted.

4.2 The fire resistance of a building element which does not explicitly appear in the Appendix tables can be established if one or more elements of same design but different dimensions have been listed in the tables. For walls, the existing element must be thicker than the one listed. For floor/ceiling assemblies, the assembly listed in the table must have the same or less cover and the same or thinner slab constructed of the same material as the actual floor/ceiling assembly. For other structural elements, the element listed in the table must be of a similar design but with less cover thickness. The fire resistance in all instances shall be the fire resistance recommended in the table. This is subject to the following limitations:

The actual element in the rehabilitated building shall be constructed of the same materials as listed in the table. Only the following dimensions may vary from those specified: for walls, the overall thickness must exceed that specified in the table; for floor/ceiling assemblies, the thickness of the cover and the slab must be greater than, or equal to, that specified in the table; for other structural elements, the thickness of the cover must be greater than that specified in the table.

All penetrations in the building element or its cover for services such as electricity, plumbing or HVAC shall be packed with noncombustible cementitious materials and so fixed that the packing material will not fall out when it loses its water of hydration.

The effects of age and wear and tear shall be repaired so that the building element is sound and the original thickness of all components, particularly covers and floor slabs, is maintained.

This approach is an application of the “thickness design” concept presented in Section 3.3 of the guideline. There should be many instances when a thicker building element was utilized than the one listed in the Appendix tables. This guideline recognizes the inherent superiority of a thicker design. (Note: “Thickness design” for floor/ceiling assemblies and structural elements refers to cover and slab thickness rather than total thickness.)

The “thickness design” concept is essentially a special case of Harmathy’s Rules (specifically Rules 1 and 2). It should be recognized that the only source of data is the Appendix tables. If other data are used, it must be in connection with the approach below.

4.3 The fire resistance of building elements can be established by applying Harmathy’s Ten Rules of Fire Resistance Ratings as set forth in Section 3.2 of the guideline. This is subject to the following limitations:

The data from the tables can be utilized subject to the limitations in Section 4.2.

Test reports from recognized journals or published papers can be used to support data utilized in applying Harmathy’s Rules.

Calculations utilizing recognized and well established computational techniques can be used in applying Harmathy’s Rules. These include, but are not limited to, analysis of heat flow, mechanical properties, deflections and load bearing capacity.

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APPENDIX

INTRODUCTION

The fire-resistance tables that follow are a part of Resource A and provide a tabular form of assigning fire-resistance ratings to various archaic building elements and assemblies.

These tables for archaic materials and assemblies do for archaic materials what Tables 721.1(1) through 721.1(3) of the California Building Code [®] do for more modern building elements and assemblies. The fire-resistance tables of Resource A should be used as described in the “Purpose and Procedure” that follows the table of contents for these tables.

TABLE OF CONTENTS

Purpose and Procedure RESOURCE A-19

Section I—Walls

1.1.1 Masonry 0 in. to less than 4 in. thick RESOURCE A-20

1.1.2 Masonry 4 in. to less than 6 in. thick RESOURCE A-23

1.1.3 Masonry 6 in. to less than 8 in. thick RESOURCE A-29

1.1.4 Masonry 8 in. to less than 10 in. thick RESOURCE A-33

1.1.5 Masonry 10 in. to less than 12 in. thick RESOURCE A-40

1.1.6 Masonry 12 in. to less than 14 in. thick RESOURCE A-43

1.1.7 Masonry 14 in. or more thick RESOURCE A-48

1.2.1 Metal Frame 0 in. to less than 4 in. thick RESOURCE A-51

1.2.2 Metal Frame 4 in. to less than 6 in. thick RESOURCE A-54

1.2.3 Metal Frame 6 in. to less than 8 in. thick RESOURCE A-55

1.2.4 Metal Frame 8 in. to less than 10 in. thick RESOURCE A-56

1.3.1 Wood Frame 0 in. to less than 4 in. thick RESOURCE A-56

1.3.2 Wood Frame 4 in. to less than 6 in. thick RESOURCE A-57

1.3.3 Wood Frame 6 in. to less than 8 in. thick RESOURCE A-63

1.4.1 Miscellaneous Materials 0 in. to less than 4 in. thick RESOURCE A-64

1.4.2 Miscellaneous Materials 4 in. to less than 6 in. thick RESOURCE A-64

1.5.1 Finish Ratings—Inorganic Materials RESOURCE A-65

1.5.2 Finish Ratings—Organic Materials RESOURCE A-66

Section II—Columns

2.1.1 Reinforced Concrete Minimum Dimension 0 in. to less than 6 in. RESOURCE A-67

2.1.2 Reinforced Concrete Minimum Dimension 10 in. to less than 12 in. RESOURCE A-67

2.1.3 Reinforced Concrete Minimum Dimension 12 in. to less than 14 in. RESOURCE A-70

2.1.4 Reinforced Concrete Minimum Dimension 14 in. to less than 16 in. RESOURCE A-70

2.1.5 Reinforced Concrete Minimum Dimension 16 in. to less than 18 in. RESOURCE A-71

2.1.6 Reinforced Concrete Minimum Dimension 18 in. to less than 20 in. RESOURCE A-73

2.1.7 Reinforced Concrete Minimum Dimension 20 in. to less than 22 in. RESOURCE A-74

2.1.8 Hexagonal Reinforced Concrete Minimum Dimension 12 in. to less than 14 in. RESOURCE A-75

2.1.9 Hexagonal Reinforced Concrete Minimum Dimension 14 in. to less than 16 in. RESOURCE A-75

2.1.10 Hexagonal Reinforced Concrete Minimum Dimension 16 in. to less than 18 in. RESOURCE A-76

2.1.11 Hexagonal Reinforced Concrete Minimum Dimension 20 in. to less than 22 in. RESOURCE A-76

2.2 Round Cast Iron Columns Minimum Dimension RESOURCE A-76

2.3 Steel Columns—Gypsum Encasements Minimum Area of Solid Material RESOURCE A-77

2.4 Timber Minimum Dimension RESOURCE A-78

2.5.1.1 Steel Columns—Concrete Encasements Minimum Dimension less than 6 in. RESOURCE A-78

2.5.1.2 Steel Columns—Concrete Encasements Minimum Dimension 6 in. to less than 8 in. RESOURCE A-79

2.5.1.3 Steel Columns—Concrete Encasements Minimum Dimension 8 in. to less than 10 in. RESOURCE A-79

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2.5.1.4 Steel Columns—Concrete Encasements Minimum Dimension 10 in. to less than 12 in. RESOURCE A-81

2.5.1.5 Steel Columns—Concrete Encasements Minimum Dimension 12 in. to less than 14 in. RESOURCE A-84

2.5.1.6 Steel Columns—Concrete Encasements Minimum Dimension 14 in. to less than 16 in. RESOURCE A-85

2.5.1.7 Steel Columns—Concrete Encasements Minimum Dimension 16 in. to less than 18 in. RESOURCE A-86

2.5.2.1 Steel Columns—Brick and Block Encasements Minimum Dimension 10 in. to less than 12 in. RESOURCE A-87

2.5.2.2 Steel Columns—Brick and Block Encasements Minimum Dimension 12 in. to less than 14 in. RESOURCE A-87

2.5.2.3 Steel Columns—Brick and Block Encasements Minimum Dimension 14 in. to less than 16 in. RESOURCE A-88

2.5.3.1 Steel Columns—Plaster Encasements Minimum Dimension 6 in. to less than 8 in. RESOURCE A-88

2.5.3.2 Steel Columns—Plaster Encasements Minimum Dimension 8 in. to less than 10 in. RESOURCE A-89

2.5.4.1 Steel Columns—Miscellaneous Encasements Minimum Dimension 6 in. to less than 8 in. RESOURCE A-89

2.5.4.2 Steel Columns—Miscellaneous Encasements Minimum Dimension 8 in. to less than 10 in. RESOURCE A-89

2.5.4.3 Steel Columns—Miscellaneous Encasements Minimum Dimension 10 in. to less than 12 in. RESOURCE A-90

2.5.4.4 Steel Columns—Miscellaneous Encasements Minimum Dimension 12 in. to less than 14 in. RESOURCE A-90

Section III—Floor/Ceiling Assemblies

3.1 Reinforced Concrete RESOURCE A-91

3.2 Steel Structural Elements RESOURCE A-96

3.3 Wood Joist RESOURCE A-101

3.4 Hollow Clay Tile with Reinforced Concrete RESOURCE A-104

Section IV—Beams

4.1.1 Reinforced Concrete Depth 10 in. to less than 12 in. RESOURCE A-107

4.1.2 Reinforced Concrete Depth 12 in. to less than 14 in. RESOURCE A-109

4.1.3 Reinforced Concrete Depth 14 in. to less than 16 in. RESOURCE A-110

4.2.1 Reinforced Concrete—Unprotected Depth 10 in. to less than 12 in. RESOURCE A-110

4.2.2 Steel—Concrete Protection Depth 10 in. to less than 12 in. RESOURCE A-111

Section V—Doors

5.1 Resistance of Doors to Fire Exposure RESOURCE A-112

Bibliography RESOURCE A-115

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PURPOSE AND PROCEDURE

The tables and histograms which follow are to be used only within the analytical framework detailed in the main body of this guideline.

Histograms precede any table with 10 or more entries. The use and interpretation of these histograms is explained in Section 2 of the guideline. The tables are in a format similar to that found in the model building codes. The following example, taken from an entry in Table 1.1.2, best explains the table format.

1. Item Code. The item code consists of a four place series in the general form w-x-y-z in which each member of the series denotes the following:

w = Type of building element (e.g., W=Walls; F=Floors, etc.). x = The building element thickness rounded down to the nearest 1-inch increment (e.g., 4 [5] / 8 inches is rounded off to 4 inches).

y = The general type of material from which the building element is constructed (e.g., M=Masonry; W=Wood, etc.).

z = The item number of the particular building element in a given table.

The item code shown in the example W-4-M-50 denotes the following:

W = Wall, as the building element.

4 = Wall thickness in the range of 4 inches (102 mm) to less than 5 inches (127 mm).

M = Masonry construction.

50 = The 50th entry in Table 1.1.2. 2. Critical Dimension. The specific name or heading of this column identifies the dimension which, if varied, has the greatest impact on fire resistance. The critical dimension for walls, in the example here, is thickness. It is different for other building elements (e.g., depth for beams; membrane thickness for some floor/ceiling assemblies). The table entry is the named dimension of the building element measured at the time of actual testing to within ± [1] / 8 inch (3.2 mm) tolerance. The thickness tabulated includes facings where facings are a part of the wall construction. 3. Construction Details. The construction details provide a brief description of the manner in which the building element was constructed.

4. Performance. This heading is subdivided into two columns. The column labeled “Load” will either list the load that the building element was subjected to during the fire test or it will contain a note number which will list the load and any other significant details. If the building element was not subjected to a load during the test, this column will contain “n/a,” which means “not applicable.”

The second column under performance is labeled “Time” and denotes the actual fire endurance time observed in the fire test.

5. Reference Number. This heading is subdivided into three columns: Pre-BMS-92; BMS-92; and Post-BMS-92. The table entry under this column is the number in the Bibliography of the original source reference for the test data.
6. Notes. Notes are provided at the end of each table to allow a more detailed explanation of certain aspects of the test. In certain tables the notes given to this column have also been listed under the “Construction Details” and/or “Load” columns.
7. Rec. Hours. This column lists the recommended fire endurance rating, in hours, of a building element. In some cases, the recommended fire endurance will be less than that listed under the “Time” column. In no case is the “Rec. Hours” greater than given in the “Time” column.

EXAMPLE ENTRY

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

SECTION I—WALLS

FIGURE 1.1.1

MASONRY WALLS 0 ″ TO LESS THAN 4 ″ THICK

10

5

0

MBER OF
The number in each box is
EMBLIES
keyed to the last number in the
Item Code column in the table.
For example:
W-3-M-20
20
19
18
14 17
13 5
12 15 4 8 22 6
11 10 9 16 3 7 1 21 2

0 1 2 3 4

FIRE-RESISTANCE RATING (HOURS)

TABLE 1.1.1
MASONRY WALLS
0″ TO LESS THAN 4″ THICK

RESOURCE A-20 2025 CALIFORNIA EXISTING BUILDING CODE

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.1.1—continued
MASONRY WALLS
0″ TO LESS THAN 4″ THICK

For SI: 1 inch = 25.4 mm, 1 pound per square inch = 0.00689 MPa, °C = [(°F) - 32]/1.8.

Notes:

1. Failure mode—flame thru.

2. Passed 2-hour fire test (Grade “C” fire res. - British).

3. Passed hose stream test.

4. Tested at NBS under ASA Spec. No. A2-1934. As non-load-bearing partitions.

5. Tested at NBS under ASA Spec. No. 42-1934 (ASTM C19-33), except that hose stream testing where carried out was run on test specimens exposed for full test duration, not for a reduced period as is contemporarily done.

6. Failure by thermal criteria—maximum temperature rise 325°F.

7. Hose stream failure.

8. Hose stream—pass.

9. Specimen removed prior to any failure occurring.

10. Failure mode—collapse.

11. For clay tile walls, unless the source or density of the clay can be positively identified or determined, it is suggested that the lowest hourly rating for the fire endurance of a clay tile partition of that thickness be followed. Identified sources of clay showing longer fire endurance can lead to longer time recommendations.

12. See appendix for construction and design details for clay tile walls.

13. Load: 80 psi for gross wall area.

14. One cell in wall thickness.

15. Two cells in wall thickness.

16. Double shells plus one cell in wall thickness.

17. One cell in wall thickness, cells filled with broken tile, crushed stone, slag cinders or sand mixed with mortar.

18. Dense hard-burned clay or shale tile.

19. Medium-burned clay tile.

20. Not less than [5] / 8 inch thickness of 1:3 sanded gypsum plaster.

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.1.1—continued

MASONRY WALLS 0 ″ TO LESS THAN 4 ″ THICK

21. Units of not less than 30 percent solid material.
22. Units of not less than 40 percent solid material.
23. Units of not less than 50 percent solid material.
24. Units of not less than 45 percent solid material.
25. Units of not less than 60 percent solid material.
26. All tiles laid in Portland cement-lime mortar.
27. Blocks laid in 1:3 sanded gypsum mortar voids in blocks not to exceed 30 percent.
28. Units of expanded slag or pumice aggregate.
29. Units of crushed limestone, blast furnace, slag, cinders and expanded clay or shale.
30. Units of calcareous sand and gravel. Coarse aggregate, 60 percent or more calcite and dolomite.
31. Units of siliceous sand and gravel. Ninety percent or more quartz, chert or flint.
32. Unit at least 49 percent solid.
33. Unit at least 62 percent solid.
34. Unit at least 65 percent solid.
35. Unit at least 73 percent solid.
36. Ratings based on one unit and one cell in wall thickness.
37. Minimum of [1] / 2 inch—1:3 sanded gypsum plaster.
38. Non-load-bearing.
39. See clay tile partition design construction drawings below.

RESOURCE A-22 2025 CALIFORNIA EXISTING BUILDING CODE

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NUMBER OF ASSEMBLIES

15

10

5

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

FIGURE 1.1.2

MASONRY WALLS 4 ″ TO LESS THAN 6 ″ THICK

0

0 1 2 3 4

FIRE-RESISTANCE RATING (HOURS)

TABLE 1.1.2
MASONRY WALLS
4″ TO LESS THAN 6″ THICK

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.1.2—continued
MASONRY WALLS
4″ TO LESS THAN 6″ THICK

RESOURCE A-24 2025 CALIFORNIA EXISTING BUILDING CODE

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.1.2—continued
MASONRY WALLS
4″ TO LESS THAN 6″ THICK

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.1.2—continued
MASONRY WALLS
4″ TO LESS THAN 6″ THICK

__

RESOURCE A-26 2025 CALIFORNIA EXISTING BUILDING CODE

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.1.2—continued
MASONRY WALLS
4″ TO LESS THAN 6″ THICK

For SI: 1 inch = 25.4 mm, 1 pound per square inch = 0.00689 MPa.

Notes:

1. Tested as NBS under ASA Spec. No. A 2-1934.
2. Failure mode—maximum temperature rise.
3. Treated at NBS under ASA Spec. No. 42-1934 (ASTM C19-53) except that hose stream testing where carried out was run on test specimens exposed for full test duration, not for a reduced period as is contemporarily done.
4. For clay tile walls, unless the source the clay can be positively identified, it is suggested that the most pessimistic hour rating for the fire endurance of a clay tile partition of that thickness be followed. Identified sources of clay showing longer fire endurance can lead to longer time recommendations.

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.1.2—continued

MASONRY WALLS 4 ″ TO LESS THAN 6 ″ THICK

5. See appendix for construction and design details for clay tile walls.

6. Failure mode—flame thru or crack formation showing flames.

7. Hole formed at 25 minutes; partition collapsed at 42 minutes on removal from furnace.

8. Failure mode—collapse.

9. Hose stream pass.

10. Hose stream hole formed in specimen.

11. Load: 80 psi for gross wall cross-sectional area.

12. One cell in wall thickness.

13. Two cells in wall thickness.

14. Double cells plus one cell in wall thickness.

15. One cell in wall thickness, cells filled with broken tile, crushed stone, slag, cinders or sand mixed with mortar.

16. Dense hard-burned clay or shale tile.

17. Medium-burned clay tile.

18. Not less than [5] / 8 inch thickness of 1:3 sanded gypsum plaster.

19. Units of not less than 30 percent solid material.

20. Units of not less than 40 percent solid material.

21. Units of not less than 50 percent solid material.

22. Units of not less than 45 percent solid material.

23. Units of not less than 60 percent solid material.

24. All tiles laid in Portland cement-lime mortar.

25. Minimum [1] / 2 inch—1:3 sanded gypsum plaster.

26. Laid in 1:3 sanded gypsum mortar. Voids in hollow units not to exceed 30 percent.

27. Units of expanded slag or pumice aggregate.

28. Units of crushed limestone, blast furnace slag, cinders and expanded clay or shale.

29. Units of calcareous sand and gravel. Coarse aggregate, 60 percent or more calcite and dolomite.

30. Units of siliceous sand and gravel. Ninety percent or more quartz, chert or flint.

31. Unit at least 49 percent solid.

32. Unit at least 62 percent solid.

33. Unit at least 65 percent solid.

34. Unit at least 73 percent solid.

35. Ratings based on one unit and one cell in wall thickness.

36. See clay tile partition design construction drawings below.

RESOURCE A-28 2025 CALIFORNIA EXISTING BUILDING CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

NUMBER OF ASSEMBLIES

10

5

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

FIGURE 1.1.3

MASONRY WALLS 6 ″ TO LESS THAN 8 ″ THICK

5 6

0

0 1 2 3 4

FIRE-RESISTANCE RATING (HOURS)

TABLE 1.1.3
MASONRY WALLS
6″ TO LESS THAN 8″ THICK

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.1.3—continued
MASONRY WALLS
6″ TO LESS THAN 8″ THICK

RESOURCE A-30 2025 CALIFORNIA EXISTING BUILDING CODE

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.1.3—continued
MASONRY WALLS
6″ TO LESS THAN 8″ THICK

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.1.3—continued

MASONRY WALLS 6 ″ TO LESS THAN 8 ″ THICK

For SI: 1 inch = 25.4 mm, 1 pound per square inch = 0.00689 MPa.

Notes:

1. Tested at NBS under ASA Spec. No. 43-1934 (ASTM C19-53), except that hose stream testing where carried out was run on test specimens exposed for full test duration, not for a reduced period as is contemporarily done.

2. Failure by thermal criteria—maximum temperature rise.

3. For clay tile walls, unless the source or density of the clay can be positively identified or determined, it is suggested that the lowest hourly rating for the fire endurance of a clay tile partition of that thickness be followed. Identified sources of clay showing longer fire endurance can lead to longer time recommendations.

4. See Note 55 for construction and design details for clay tile walls.

5. Tested at NBS under ASA Spec. No. A2-1934.

6. Failure mode—collapse.

7. Collapsed on removal from furnace at 1 hour 9 minutes.

8. Hose stream—failed.

9. Hose stream—passed.

10. No end point met in test.

11. Wall collapsed at 1 hour 28 minutes.

12. One cell in wall thickness.

13. Two cells in wall thickness.

14. Double shells plus one cell in wall thickness.

15. One cell in wall thickness, cells filled with broken tile, crushed stone, slag, cinders or sand mixed with mortar.

16. Dense hard-burned clay or shale tile.

17. Medium-burned clay tile.

18. Not less than [5] / 8 inch thickness of 1:3 sanded gypsum plaster.

19. Units of not less than 30 percent solid material.

20. Units of not less than 40 percent solid material.

21. Units of not less than 50 percent solid material.

22. Units of not less than 45 percent solid material.

23. Units of not less than 60 percent solid material.

24. All tiles laid in Portland cement-lime mortar.

25. Load: 80 psi for gross cross-sectional area of wall.

26. Three cells in wall thickness.

27. Minimum percent of solid material in concrete units = 52.

28. Minimum percent of solid material in concrete units = 54.

29. Minimum percent of solid material in concrete units = 55.

30. Minimum percent of solid material in concrete units = 57.

31. Minimum percent of solid material in concrete units = 62.

32. Minimum percent of solid material in concrete units = 65.

33. Minimum percent of solid material in concrete units = 70.

34. Minimum percent of solid material in concrete units = 76.

35. Not less than [1] / 2 inch of 1:3 sanded gypsum plaster.

36. Noncombustible or no members framed into wall.

37. Combustible members framed into wall.

38. One unit in wall thickness.

39. Two units in wall thickness.

40. Three units in wall thickness.

41. Concrete units made with expanded slag or pumice aggregates.

42. Concrete units made with expanded burned clay or shale, crushed limestone, air-cooled slag or cinders.

43. Concrete units made with calcareous sand and gravel. Coarse aggregate, 60 percent or more calcite and dolomite.

44. Concrete units made with siliceous sand and gravel. Ninety percent or more quartz, chert or flint.

45. Laid in 1:3 sanded gypsum mortar.

46. Units of expanded slag or pumice aggregate.

47. Units of crushed limestone, blast furnace, slag, cinder and expanded clay or shale.

48. Units of calcareous sand and gravel. Coarse aggregate, 60 percent or more calcite and dolomite.

49. Units of siliceous sand and gravel. Ninety percent or more quartz, chert or flint.

50. Unit minimum 49 percent solid.

51. Unit minimum 62 percent solid.

52. Unit minimum 65 percent solid.

53. Unit minimum 73 percent solid.

54. Ratings based on one unit and one cell in wall section.

55. See clay tile partition design construction drawings:

RESOURCE A-32 2025 CALIFORNIA EXISTING BUILDING CODE

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

FIGURE 1.1.4

MASONRY WALLS

8² TO LESS THAN 10² THICK

NUMBER OF ASSEMBLIES

15

10

5

0

OF LIES

OF LIES 107
110
92
29
40
44
15
62
67
68
69
78
96
80
17
20
42
13
82
98
11
34
36
7
38
41
49
84
89
93
5
9
35
3
37
43
45
75
39
79
95
97
109
91
8
14
16
1
47
77
81
99
4
6
10
2
12
57
83
102
112|

0 1 2 3 4 5 6

FIRE-RESISTANCE RATING (HOURS)

7 8 9 10

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.1.4
MASONRY WALLS
8″ TO LESS THAN 10″ THICK

RESOURCE A-34 2025 CALIFORNIA EXISTING BUILDING CODE

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.1.4—continued
MASONRY WALLS
8″ TO LESS THAN 10″ THICK

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.1.4—continued
MASONRY WALLS
8″ TO LESS THAN 10″ THICK

RESOURCE A-36 2025 CALIFORNIA EXISTING BUILDING CODE

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.1.4—continued
MASONRY WALLS
8″ TO LESS THAN 10″ THICK

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.1.4—continued
MASONRY WALLS
8″ TO LESS THAN 10″ THICK

For SI: 1 inch = 25.4 mm, 1 pound per square inch = 0.00689 MPa.

Notes:

1. Tested at NBS under ASA Spec. No. 43-1934 (ASTM C19-53).

2. One unit in wall thickness.

3. Two units in wall thickness.

4. Two or three units in wall thickness.

5. Two cells in wall thickness.

RESOURCE A-38 2025 CALIFORNIA EXISTING BUILDING CODE

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.1.4—continued

MASONRY WALLS 8 ″ TO LESS THAN 10 ″ THICK

6. Three or four cells in wall thickness.

7. Four or five cells in wall thickness.

8. Five or six cells in wall thickness.

9. Minimum percent of solid materials in units = 40%.

10. Minimum percent of solid materials in units = 43%.

11. Minimum percent of solid materials in units = 46%.

12. Minimum percent of solid materials in units = 48%.

13. Minimum percent of solid materials in units = 49%.

14. Minimum percent of solid materials in units = 45%.

15. Minimum percent of solid materials in units = 51%.

16. Minimum percent of solid materials in units = 53%.

17. Not less than [5] / 8 inch thickness of 1:3 sanded gypsum plaster.

18. Noncombustible or no members framed into wall.

19. Combustible members framed into wall.

20. Load: 80 psi for gross cross-sectional area of wall.

21. Portland cement-lime mortar.

22. Failure mode—thermal.

23. British test.

24. Passed all criteria.

25. Failed by sudden collapse with no preceding signs of impending failure.

26. One cell in wall thickness.

27. Two cells in wall thickness.

28. Three cells in wall thickness.

29. Minimum percent of solid material in concrete units = 52.

30. Minimum percent of solid material in concrete units = 54.

31. Minimum percent of solid material in concrete units = 55.

32. Minimum percent of solid material in concrete units = 57.

33. Minimum percent of solid material in concrete units = 60.

34. Minimum percent of solid material in concrete units = 62.

35. Minimum percent of solid material in concrete units = 65.

36. Minimum percent of solid material in concrete units = 70.

37. Minimum percent of solid material in concrete units = 76.

38. Not less than [1] / 2 inch of 1:3 sanded gypsum plaster.

39. Three units in wall thickness.

40. Concrete units made with expanded slag or pumice aggregates.

41. Concrete units made with expanded burned clay or shale, crushed limestone, air-cooled slag or cinders.

42. Concrete units made with calcareous sand and gravel. Coarse aggregate, 60 percent or more calcite and dolomite.

43. Concrete units made with siliceous sand and gravel. Ninety percent or more quartz, chert and dolomite.

44. Load: 120 psi for gross cross-sectional area of wall.

45. Load: 160 psi for gross cross-sectional area of wall.

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

FIGURE 1.1.5

MASONRY WALLS 10 ″ TO LESS THAN 12 ″ THICK

NUMBER OF ASSEMBLIES

10

5

0

0 1 2 3 4 5

FIRE-RESISTANCE RATING (HOURS)

6 7

TABLE 1.1.5
MASONRY WALLS
10″ TO LESS THAN 12″ THICK

RESOURCE A-40 2025 CALIFORNIA EXISTING BUILDING CODE

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.1.5—continued
MASONRY WALLS
10″ TO LESS THAN 12″ THICK

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.1.5—continued

MASONRY WALLS 10 ″ TO LESS THAN 12 ″ THICK

For SI: 1 inch = 25.4 mm, 1 pound per square inch = 0.00689 MPa.

Notes:

1. Tested at NBS under ASA Spec. No. A2-1934.

2. One unit in wall thickness.

3. Two units in wall thickness.

4. Two or three units in wall thickness.

5. Two cells in wall thickness.

6. Three or four cells in wall thickness.

7. Four or five cells in wall thickness.

8. Five or six cells in wall thickness.

9. Minimum percent of solid materials in units = 40%.

10. Minimum percent of solid materials in units = 43%.

11. Minimum percent of solid materials in units = 46%.

12. Minimum percent of solid materials in units = 48%.

13. Minimum percent of solid materials in units = 49%.

14. Minimum percent of solid materials in units = 45%.

15. Minimum percent of solid materials in units = 51%.

16. Minimum percent of solid materials in units = 53%.

17. Not less than [5] / 8 inch thickness of 1:3 sanded gypsum plaster.

18. Noncombustible or no members framed into wall.

19. Combustible members framed into wall.

20. Load: 80 psi for gross cross-sectional area of wall.

21. Portland cement-lime mortar.

22. Failure mode—thermal.

23. British test.

24. Passed all criteria.

25. Failed by sudden collapse with no preceding signs of impending failure.

26. One cell in wall thickness.

27. Two cells in wall thickness.

28. Three cells in wall thickness.

29. Minimum percent of solid material in concrete units = 52%.

30. Minimum percent of solid material in concrete units = 54%.

31. Minimum percent of solid material in concrete units = 55%.

32. Minimum percent of solid material in concrete units = 57%.

33. Minimum percent of solid material in concrete units = 60%.

34. Minimum percent of solid material in concrete units = 62%.

35. Minimum percent of solid material in concrete units = 65%.

36. Minimum percent of solid material in concrete units = 70%.

37. Minimum percent of solid material in concrete units = 76%.

38. Not less than [1] / 2 inch of 1:3 sanded gypsum plaster.

39. Three units in wall thickness.

40. Concrete units made with expanded slag or pumice aggregates.

41. Concrete units made with expanded burned clay or shale, crushed limestone, air-cooled slag or cinders.

42. Concrete units made with calcareous sand and gravel. Coarse aggregate, 60 percent or more calcite and dolomite.

RESOURCE A-42 2025 CALIFORNIA EXISTING BUILDING CODE

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

FIGURE 1.1.6

MASONRY WALLS 12 ″ TO LESS THAN 14 ″ THICK

10

5

0

BER OF
The number in each box is
MBLIES
keyed to the last number in the
81 84 Item Code column in the Table.
For example:
80 83
W-12-M-42
76 82 42
64 87 78 39
59 61 77 37
50 58 47 63 85 34
46 48 60 62 57 31 49 79 23 73
30 44 53 55 56 27 45 75 9 70
51 26 20 22 52 54 21 41 72 7 66 74
33 18 14 16 17 29 8 36 68 4 24 43 35 38 67
32 28 12 11 13 15 19 3 25 65 86 2 10 1 5 6 40 59 71

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14

1 2 3 4

5 6 7 8 9 10 11

15 16 17

FIRE-RESISTANCE RATING (HOURS)

TABLE 1.1.6
MASONRY WALLS
12″ TO LESS THAN 14″ THICK

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.1.6—continued
MASONRY WALLS
12″ TO LESS THAN 14″ THICK

RESOURCE A-44 2025 CALIFORNIA EXISTING BUILDING CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.1.6—continued
MASONRY WALLS
12″ TO LESS THAN 14″ THICK

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.1.6—continued
MASONRY WALLS
12″ TO LESS THAN 14″ THICK

RESOURCE A-46 2025 CALIFORNIA EXISTING BUILDING CODE

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.1.6—continued
MASONRY WALLS
12″ TO LESS THAN 14″ THICK

For SI: 1 inch = 25.4 mm, 1 pound per square inch = 0.00689 MPa.

Notes:

1. Tested at NBS under ASA Spec. No. A2-1934.

2. One unit in wall thickness.

3. Two units in wall thickness.

4. Two or three units in wall thickness.

5. Two cells in wall thickness.

6. Three or four cells in wall thickness.

7. Four or five cells in wall thickness.

8. Five or six cells in wall thickness.

9. Minimum percent of solid materials in units = 40%.

10. Minimum percent of solid materials in units = 43%.

11. Minimum percent of solid materials in units = 46%.

12. Minimum percent of solid materials in units = 48%.

13. Minimum percent of solid materials in units = 49%.

14. Minimum percent of solid materials in units = 45%.

15. Minimum percent of solid materials in units = 51%.

16. Minimum percent of solid materials in units = 53%.

17. Not less than [5] / 8 inch thickness of 1:3 sanded gypsum plaster.

18. Noncombustible or no members framed into wall.

19. Combustible members framed into wall.

20. Load: 80 psi for gross area.

21. Portland cement-lime mortar.

22. Failure mode–thermal.

23. British test.

24. Passed all criteria.

25. Failed by sudden collapse with no preceding signs of impending failure.

26. One cell in wall thickness.

27. Two cells in wall thickness.

28. Three cells in wall thickness.

29. Minimum percent of solid material in concrete units = 52%.

30. Minimum percent of solid material in concrete units = 54%.

31. Minimum percent of solid material in concrete units = 55%.

32. Minimum percent of solid material in concrete units = 57%.

33. Minimum percent of solid material in concrete units = 60%.

34. Minimum percent of solid material in concrete units = 62%.

35. Minimum percent of solid material in concrete units = 65%.

36. Minimum percent of solid material in concrete units = 70%.

37. Minimum percent of solid material in concrete units = 76%.

38. Not less than [1] / 2 inch of 1:3 sanded gypsum plaster.

39. Three units in wall thickness.

40. Concrete units made with expanded slag or pumice aggregates.

41. Concrete units made with expanded burned clay or shale, crushed limestone, air-cooled slag or cinders.

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TABLE 1.1.6—continued

MASONRY WALLS 12 ″ TO LESS THAN 14 ″ THICK

42. Concrete units made with calcareous sand and gravel. Coarse aggregate, 60 percent or more calcite and dolomite.
43. Concrete units made with siliceous sand and gravel. Ninety percent or more quartz, chert or flint.
44. Load: 160 psi of gross wall cross-sectional area.
45. Load: 120 psi of gross wall cross-sectional area.

FIGURE 1.1.7

MASONRY WALLS

14 ″ OR MORE THICK

NUMBER OF ASSEMBLIES

10

5

0

1 2 3 4

5 6 7 8 9

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14

FIRE-RESISTANCE RATING (HOURS)

TABLE 1.1.7
MASONRY WALLS
14″ OR MORE THICK

RESOURCE A-48 2025 CALIFORNIA EXISTING BUILDING CODE

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TABLE 1.1.7—continued
MASONRY WALLS
14″ OR MORE THICK

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.1.7—continued
MASONRY WALLS
14″ OR MORE THICK

For SI: 1 inch = 25.4 mm, 1 pound per square inch = 0.00689 MPa. Notes: 1 Tested at NBS under ASA Spec. No. A2-1934. 2. One unit in wall thickness.

3. Two units in wall thickness.

4. Two or three units in wall thickness.

5. Two cells in wall thickness.

6. Three or four cells in wall thickness.

7. Four or five cells in wall thickness.

8. Five or six cells in wall thickness.

9. Minimum percent of solid materials in units = 40%.

10. Minimum percent of solid materials in units = 43%.

11. Minimum percent of solid materials in units = 46%.

12. Minimum percent of solid materials in units = 48%.

13. Minimum percent of solid materials in units = 49%.

14. Minimum percent of solid materials in units = 45%.

15. Minimum percent of solid materials in units = 51%.

16. Minimum percent of solid materials in units = 53%.

17. Not less than [5] / 8 inch thickness of 1:3 sanded gypsum plaster.

18. Noncombustible or no members framed into wall.

19. Combustible members framed into wall.

20. Load: 80 psi for gross area.

21. Portland cement-lime mortar.

22. Failure mode—thermal.

23. British test.

24. Passed all criteria.

25. Failed by sudden collapse with no preceding signs of impending failure.

26. One cell in wall thickness.

27. Two cells in wall thickness.

28. Three cells in wall thickness.

29. Minimum percent of solid material in concrete units = 52%.

30. Minimum percent of solid material in concrete units = 54%.

31. Minimum percent of solid material in concrete units = 55%.

32. Minimum percent of solid material in concrete units = 57%.

33. Minimum percent of solid material in concrete units = 60%.

34. Minimum percent of solid material in concrete units = 62%.

35. Minimum percent of solid material in concrete units = 65%.

36. Minimum percent of solid material in concrete units = 70%.

37. Minimum percent of solid material in concrete units = 76%.

38. Not less than [1] / 2 inch of 1:3 sanded gypsum plaster.

39. Three units in wall thickness.

40. Concrete units made with expanded slag or pumice aggregates.

41. Concrete units made with expanded burned clay or shale, crushed limestone, air-cooled slag or cinders.

42. Concrete units made with calcareous sand and gravel. Coarse aggregate, 60 percent or more calcite and dolomite.

43. Concrete units made with siliceous sand and gravel. Ninety percent or more quartz, chert or flint.

RESOURCE A-50 2025 CALIFORNIA EXISTING BUILDING CODE

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NUMBER OF ASSEMBLIES

15

10

5

0

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

FIGURE 1.2.1

METAL FRAME WALLS

0 ″ TO LESS THAN 4 ″ THICK

0 1 2 3 4

FIRE-RESISTANCE RATING (HOURS)

TABLE 1.2.1
METAL FRAME WALLS
0″ TO LESS THAN 4″ THICK

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TABLE 1.2.1—continued
METAL FRAME WALLS
0″ TO LESS THAN 4″ THICK

RESOURCE A-52 2025 CALIFORNIA EXISTING BUILDING CODE

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.2.1—continued
METAL FRAME WALLS
0″ TO LESS THAN 4″ THICK

For SI: 1 inch = 25.4 mm.

Notes:

1. Failure mode—local temperature rise—back face.
2. Three-fourths inch or 1 inch channel framing—hot-rolled or strip-steel channels.
3. Reinforcement is 4-inch square mesh of No. 6 wire welded at intersections (no channels).
4. Ratings are for any usual type of non-load-bearing metal framing providing 2 inches (or more) air space.

General Note:

The construction details of the wall assemblies are as complete as the source documentation will permit. Data on the method of attachment of facings and the gage of steel studs was provided when known. The cross-sectional area of the steel stud can be computed, thereby permitting a reasoned estimate of actual loading conditions. For load-bearing assemblies, the maximum allowable stress for the steel studs has been provided in the table “Notes.” More often, it is the thermal properties of the facing materials, rather than the specific gage of the steel, that will determine the degree of fire resistance. This is particularly true for nonbearing wall assemblies.

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9

TABLE 1.2.2
METAL FRAME WALLS
4″ TO LESS THAN 6″ THICK

RESOURCE A-54 2025 CALIFORNIA EXISTING BUILDING CODE

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.2.2—continued
METAL FRAME WALLS
4″ TO LESS THAN 6″ THICK

For SI: 1 inch = 25.4 mm, 1 pound per square inch = 0.00689 MPa.

Notes:

1. Failure mode—local back face temperature rise.
2. Ratings are for any usual type of nonbearing metal framing providing a minimum 2-inch air space.
3. Facing materials secured to lightweight steel studs not less than 3 inches deep.
4. Rating based on loading to develop a maximum stress of 7270 psi for net area of each stud.
5. Spacing of steel studs must be sufficient to develop adequate rigidity in the metal-lath or gypsum-plaster base.
6. As per Note 4 but load/stud not to exceed 5120 psi.

General Note:

The construction details of the wall assemblies are as complete as the source documentation will permit. Data on the method of attachment of facings and the gage of steel studs was provided when known. The cross-sectional area of the steel stud can be computed, thereby permitting a reasoned estimate of actual loading conditions. For load-bearing assemblies, the maximum allowable stress for the steel studs has been provided in the table “Notes.” More often, it is the thermal properties of the facing materials, rather than the specific gage of the steel, that will determine the degree of fire resistance. This is particularly true for nonbearing wall assemblies.

by permitting a reasoned estimate of actual loading conditions. For load-bearing assemblies, the maximum allowable stress for the steel studs has been provided in the table “Notes.” More often, it is the thermal properties of the facing materials, rather than the specific gage of the steel, that will determine the degree of fire resistance. This is particularly true for nonbearing wall assemblies.

TABLE 1.2.3
METAL FRAME WALLS
6″ TO LESS THAN 8″ THICK

For SI: 1 inch = 25.4 mm, 1 pound per square inch = 0.00689 MPa.

Notes:

1. Lightweight steel studs (minimum 3 inches deep) used. Stud spacing dependent on loading, but in each case, spacing is to be such that adequate rigidity is provided to the metal lath plaster base.
2. Load is such that stress developed in studs is not greater than 5120 psi calculated from net stud area.

General Note:

The construction details of the wall assemblies are as complete as the source documentation will permit. Data on the method of attachment of facings and the gage of steel studs was provided when known. The cross-sectional area of the steel stud can be computed, thereby permitting a reasoned estimate of actual loading conditions. For load-bearing assemblies, the maximum allowable stress for the steel studs has been provided in the table “Notes.” More often, it is the thermal properties of the facing materials, rather than the specific gage of the steel, that will determine the degree of fire resistance. This is particularly true for nonbearing wall assemblies.

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.2.4
METAL FRAME WALLS
8″ TO LESS THAN 10″ THICK

For SI: 1 inch = 25.4 mm, 1 pound per square inch = 0.00689 MPa.

Notes:

1. Lightweight steel studs ≥ 3 inches in depth. Stud spacing dependent on loading, but in any case, the spacing is to be such that adequate rigidity is provided to the metal-lath plaster base.
2. Load is such that stress developed in studs is ≤ 5120 psi calculated from the net area of the stud.

General Note:

The construction details of the wall assemblies are as complete as the source documentation will permit. Data on the method of attachment of facings and the gage of steel studs was provided when known. The cross-sectional area of the steel stud can be computed, thereby permitting a reasoned estimate of actual loading conditions. For load-bearing assemblies, the maximum allowable stress for the steel studs has been provided in the table “Notes.” More often, it is the thermal properties of the facing materials, rather than the specific gage of the steel, that will determine the degree of fire resistance. This is particularly true for nonbearing wall assemblies.

by permitting a reasoned estimate of actual loading conditions. For load-bearing assemblies, the maximum allowable stress for the steel studs has been provided in the table “Notes.” More often, it is the thermal properties of the facing materials, rather than the specific gage of the steel, that will determine the degree of fire resistance. This is particularly true for nonbearing wall assemblies.

TABLE 1.3.1
WOOD FRAME WALLS
0″ TO LESS THAN 4″ THICK

For SI: 1 inch = 25.4 mm, 1 pound per square inch = 0.00689 MPa.

Notes:

1. Achieved “Grade C” fire resistance (British).
2. Nominal 2 × 4 wood studs of No. 1 common or better lumber set edgewise, 2 × 4 plates at top and bottom and blocking at mid-height of wall.
3. All horizontal joints in facing material backed by 2 × 4 blocking in wall.
4. Load: 360 psi of net stud cross-sectional area.
5. facings secured with 6d casing nails. Nail holes predrilled and 0.02 inch to 0.03 inch smaller than nail diameter.
6. The wood-wool core is a pressed excelsior slab which possesses insulating properties similar to cellulosic insulation.

RESOURCE A-56 2025 CALIFORNIA EXISTING BUILDING CODE

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

FIGURE 1.3.2 WOOD FRAME WALLS 4 ″ TO LESS THAN 6 ″ THICK

NUMBER OF ASSEMBLIES

30

10

0

0 1 2 3 4

FIRE-RESISTANCE RATING (HOURS)

TABLE 1.3.2
WOOD FRAME WALLS
4″ TO LESS THAN 6″ THICK

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TABLE 1.3.2—continued
WOOD FRAME WALLS
4″ TO LESS THAN 6″ THICK

RESOURCE A-58 2025 CALIFORNIA EXISTING BUILDING CODE

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TABLE 1.3.2—continued
WOOD FRAME WALLS
4″ TO LESS THAN 6″ THICK

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TABLE 1.3.2—continued
WOOD FRAME WALLS
4″ TO LESS THAN 6″ THICK

RESOURCE A-60 2025 CALIFORNIA EXISTING BUILDING CODE

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.3.2—continued
WOOD FRAME WALLS
4″ TO LESS THAN 6″ THICK

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TABLE 1.3.2—continued
WOOD FRAME WALLS
4″ TO LESS THAN 6″ THICK

For SI: 1 inch = 25.4 mm, 1 foot = 305 mm, 1 pound = 0.004448 kN, 1 pound per square inch = 0.00689 MPa, 1 pound per square foot = 47.9 N/m [2] .

Notes:

1. All specimens 8 feet or 8 feet 8 inches by 10 feet 4 inches, i.e. one-half of furnace size. See Note 42 for design cross section.
2. Specimens tested in tandem (two per exposure).
3. Test per ASA No. A2-1934, except where unloaded. Also, panels were of “half” size of furnace opening. Time value signifies a thermal failure time.
4. Two-inch by 4-inch studs: 16 inches on center; where 10 feet 4 inches, blocking at 2-foot 4-inch height.
5. Facing 4 feet by 8 feet, cement-asbestos board sheets, [3] / 16 inch thick.
6. Sheathing (diagonal): [25] / 32 inch by 5 [1] / 2 inch, 1 inch by 6 inches pine.
7. Facing shingles: 24 inches by 12 inches by [5] / 32 inch where used.
8. Asbestos felt: asphalt set between sheathing and shingles.
9. Load: 30,500 pounds or 360 psi/stud where load was tested.
10. Walls were tested beyond achievement of first test end point. A load-bearing time in excess of performance time indicates that, although thermal criteria were exceeded, loadbearing ability continued.
11. Wall was rated for one-hour combustible use in original source.
12. Hose steam test specimen. See table entry of similar design for recommended rating.
13. Rated one and one-fourth hour load bearing. Rated one and one-half hour non-load-bearing.
14. Failed hose stream.
15. Test terminated due to flame penetration.
16. Test terminated—local back face temperature rise.
17. Nominal 2-inch by 4-inch wood studs of No. 1 common or better lumber set edgewise. Two-inch by four-inch plates at top and bottom and blocking at mid-height of wall.
18. Cavity insulation consists of rock wool bats 1.0 lb./ft [2] of filled cavity area.
19. Cavity insulation consists of glass wool bats 0.6 lb./ft [2] of filled cavity area.
20. Cavity insulation consists of blown-in rock wool 2.0 lbs/ft [2] of filled cavity area

RESOURCE A-62 2025 CALIFORNIA EXISTING BUILDING CODE

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TABLE 1.3.2—continued

WOOD FRAME WALLS 4 ″ TO LESS THAN 6 ″ THICK

21. Mix proportions for plastered walls as follows: first ratio indicates scratch coat mix, weight of dry plaster to dry sand; second ratio indicates brown coat mix.
22. “Neat” plaster is taken to mean unsanded wood-fiber gypsum plaster.
23. Load: 360 psi of net stud cross-sectional area.
24. Rated as non-load-bearing.
25. Nominal 2-inch by 4-inch studs per Note 17, spaced at 16 inches on center.
26. Horizontal joints in facing material supported by 2-inch by 4-inch blocking within wall.
27. facings secured with 6d casing nails. Nail holes predrilled and were 0.02 to 0.03 inch smaller than nail diameter.
28. Cavity insulation consists of mineral wool bats weighing 2 lbs/ft [2] of filled cavity area.
29. Interior wall face exposed to fire.
30. Exterior wall faced exposed to fire.
31. Nominal 2-inch by 4-inch studs of yellow pine or Douglas-fir spaced 16 inches on center in a single row.
32. Studs as in Note 31 except double row, with studs in rows staggered.
33. Six roofing nails with metal-lath pads around heads to each 16-inch by 48-inch lath.
34. Areas of holes less than 2 [3] / 4 percent of area of lath.
35. Wood laths were nailed with either 3d or 4d nails, one nail to each bearing, and the end joining broken every seventh course.
36. One-half-inch thick fiberboard plaster base nailed with 3d or 4d common wire nails spaced 4 to 6 inches on center.
37. Seven-eighths-inch thick fiberboard plaster base nailed with 5d common wire nails spaced 4 to 6 inches on center.
38. Mineral wood bats 1.05 to 1.25 lbs/ft [2] with waterproofed-paper backing.
39. Blown-in mineral wool insulation, 2.2 lbs/ft [2] .
40. Mineral wool bats, 1.4 lbs/ft [2] with waterproofed-paper backing.
41. Mineral wood bats, 0.9 lb./ft [2] .
42. See wall design diagram below:

43. Duplicate specimen of W-4-W-7, tested simultaneously with W-4-W-7 in 18-foot test furnace.

TABLE 1.3.3
WOOD FRAME WALLS
6″ TO LESS THAN 8″ THICK

For SI: 1 inch = 25.4 mm, 1 pound = 0.004448 kN, 1 pound per square inch = 0.00689 MPa, 1 pound per square foot = 47.9 N/m [2] .

Notes:

1. Nominal 2-inch by 4-inch wood studs of No. 1 common or better lumber set edgewise. Two-inch by 4-inch plates at top and bottom and blocking at mid height of wall.
2. Mix proportions for plastered walls as follows: first ratio indicates scratch coat mix, weight of dry plaster to dry sand; second ratio indicates brown coat mix.
3. Load: 360 psi of net stud cross-sectional area.
4. Nominal 2-inch by 4-inch studs of yellow pine of Douglas-fir spaced 16 inches in a double row, with studs in rows staggered.
5. Mineral wool bats, 0.19 lb./ft [2] .

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 1.4.1
MISCELLANEOUS MATERIALS WALLS
0″ TO LESS THAN 4″ THICK

For SI: 1 inch = 25.4 mm, 1 pound = 0.004448 kN.

Notes:

1. No failure reached at 1 hour.

2. These glass blocks are assumed to be solid based on other test data available for similar but hollow units which show significantly reduced fire endurance.

3. Minimum of [1] / 2 inch of 1:3 sanded gypsum plaster required to develop this rating.

TABLE 1.4.2
MISCELLANEOUS MATERIALS WALLS
4″ TO LESS THAN 6″ THICK

For SI: 1 inch = 25.4 mm.

Notes:

1. One-half inch sanded gypsum plaster. Voids in hollow blocks to be not more than 30 percent.

RESOURCE A-64 2025 CALIFORNIA EXISTING BUILDING CODE

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NUMBER OF ASSEMBLIES

10

5

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

FIGURE 1.5.1

FINISH RATINGS—INORGANIC MATERIALS

0

0 12 24 36 48

FIRE-RESISTANCE RATING (HOURS)

60

TABLE 1.5.1
FINISH RATINGS—INORGANIC MATERIALS

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TABLE 1.5.1—continued
FINISH RATINGS—INORGANIC MATERIALS

For SI: 1 inch = 25.4 mm, °C = [(°F) - 32]/1.8.

Notes:

1. The finish rating is the time required to obtain an average temperature rise of 250°F, or a single point rise of 325°F, at the interface between the material being rated and the substrate being protected.
2. Tested in accordance with the Standard Specifications for Fire Tests of Building Construction and Materials, ASA No. A2-1932.
3. Mix proportions for plasters as follows: first ratio, dry weight of plaster to dry weight of sand for scratch coat; second ratio, plaster to sand for brown coat.
4. Neat plaster means unsanded wood-fiber gypsum plaster.

being rated and the substrate being protected. 2. Tested in accordance with the Standard Specifications for Fire Tests of Building Construction and Materials, ASA No. A2-1932. 3. Mix proportions for plasters as follows: first ratio, dry weight of plaster to dry weight of sand for scratch coat; second ratio, plaster to sand for brown coat. 4. Neat plaster means unsanded wood-fiber gypsum plaster.

TABLE 1.5.2
FINISH RATINGS—ORGANIC MATERIALS

For SI: 1 inch = 25.4 mm, 1 pound = 0.004448 kN, 1 pound per square foot = 47.9 N/m [2], °C = [(°F) - 32]/1.8.

Notes:

1. The finish rating is the time required to obtain an average temperature rise of 250°F, or a single point rise of 325°F, at the interface between the material being rated and he substrate being protected.
2. Tested in accordance with the Standard Specifications for Fire Tests of Building Construction and Materials, ASA No. A2-1932.
3. Plaster ratios as follows: first ratio is for scratch coat, weight of dry plaster to weight of dry sand; second ratio is for the brown coat.

General Note:

The finish rating of thinner materials, particularly thinner woods, have not been listed because the possible effects of shrinkage, warpage and aging cannot be predicted.

RESOURCE A-66 2025 CALIFORNIA EXISTING BUILDING CODE

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

SECTION II—COLUMNS

TABLE 2.1.1
REINFORCED CONCRETE COLUMNS
MINIMUM DIMENSION 0″ TO LESS THAN 6″

Notes:

1. Collapse.

2. British test.

NUMBER OF ASSEMBLIES

15

10

5

0

0

FIGURE 2.1.2

REINFORCED CONCRETE COLUMNS

MINIMUM DIMENSION 10 ″ TO LESS THAN 12 ″

2 3 4

1

TABLE 2.1.2
REINFORCED CONCRETE COLUMNS
MINIMUM DIMENSION 10″ TO LESS THAN 12″

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TABLE 2.1.2—continued
REINFORCED CONCRETE COLUMNS
MINIMUM DIMENSION 10″ TO LESS THAN 12″

RESOURCE A-68 2025 CALIFORNIA EXISTING BUILDING CODE

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TABLE 2.1.2—continued
REINFORCED CONCRETE COLUMNS
MINIMUM DIMENSION 10″ TO LESS THAN 12″

For SI: 1 inch = 25.4 mm, 1 pound per square inch = 0.00689 MPa, 1 ton = 8.896 kN.

Notes:

1. Failure mode—collapse.
2. Passed 2-hour fire exposure.
3. Passed hose stream test.
4. Reloaded effectively after 48 hours but collapsed at load in excess of original test load.
5. Failing load was 150 tons.
6. Failing load was 112 tons.
7. Failed during hose stream test.
8. Range of load 58.8 tons (initial) to 92 tons (92 minutes) to 60 tons (80 minutes).
9. Collapsed at 44 tons in reload after 96 hours.
10. Withstood reload after 72 hours.
11. Collapsed on reload after 48 hours.

. Reloaded effectively after 48 hours but collapsed at load in excess of original test load. 5. Failing load was 150 tons. 6. Failing load was 112 tons. 7. Failed during hose stream test. 8. Range of load 58.8 tons (initial) to 92 tons (92 minutes) to 60 tons (80 minutes). 9. Collapsed at 44 tons in reload after 96 hours. 10. Withstood reload after 72 hours. 11. Collapsed on reload after 48 hours.

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TABLE 2.1.3
REINFORCED CONCRETE COLUMNS
MINIMUM DIMENSION 12″ TO LESS THAN 14″

For SI: 1 inch = 25.4 mm, 1 pound per square inch = 0.00689 MPa, 1 pound per square yard = 5.3 N/m [2] .

Notes:

1. Failure mode—unspecified structural.
2. Group I: includes concrete having calcareous aggregate containing a combined total of not more than 10 percent of quartz, chert and flint for the coarse aggregate. Group II: includes concrete having trap-rock aggregate applied without metal ties and also concrete having cinder, sandstone or granite aggregate, if held in place with wire mesh or expanded metal having not larger than 4-inch mesh, weighing not less than 1.7 lbs/yd [2], placed not more than 1 inch from the surface of the concrete. Group III: includes concrete having cinder, sandstone or granite aggregate tied with No. 5 gage steel wire, wound spirally over the column section on a pitch of 8 inches, or equivalent ties, and concrete having siliceous aggregates containing a combined total of 60 percent or more of quartz, chert and flint, if held in place with wire mesh or expanded metal having not larger than 4-inch mesh, weighing not less than 1.7 lbs/yd [2], placed not more than 1 inch from the surface of the concrete. Group IV: includes concrete having siliceous aggregates containing a combined total of 60 percent or more of quartz, chert and flint, and tied with No. 5 gage steel wire wound spirally over the column section on a pitch of 8 inches, or equivalent ties.
3. Groupings of aggregates and ties are the same as for structural steel columns protected solidly with concrete, the ties to be placed over the vertical reinforcing bars and the mesh where required, to be placed within 1 inch from the surface of the column. Column A: working loads are assumed as carried by the area of the column inside of the lines circumscribing the reinforcing steel. Column B: working loads are assumed as carried by the gross area of the column.

TABLE 2.1.4
REINFORCED CONCRETE COLUMNS
MINIMUM DIMENSION 14″ TO LESS THAN 16″

RESOURCE A-70 2025 CALIFORNIA EXISTING BUILDING CODE

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 2.1.4—continued
REINFORCED CONCRETE COLUMNS
MINIMUM DIMENSION 14″ TO LESS THAN 16″

For SI: 1 inch = 25.4 mm, 1 pound per square inch = 0.00689 MPa, 1 pound per square yard = 5.3 N/m [2] .

Notes:

1. Failure mode—main rebars buckled between links at various points.
2. Group I: includes concrete having calcareous aggregate containing a combined total of not more than 10 percent of quartz, chert and flint for the coarse aggregate. Group II: includes concrete having trap-rock aggregate applied without metal ties and also concrete having cinder, sandstone or granite aggregate, if held in place with wire mesh or expanded metal having not larger than 4-inch mesh, weighing not less than 1.7 lbs/yd [2], placed not more than 1 inch from the surface of the concrete. Group III: includes concrete having cinder, sandstone or granite aggregate tied with No. 5 gage steel wire, wound spirally over the column section on a pitch of 8 inches, or equivalent ties, and concrete having siliceous aggregates containing a combined total of 60 percent or more of quartz, chert and flint, if held in place with wire mesh or expanded metal having not larger than 4-inch mesh, weighing not less than 1.7 lbs/yd [2], placed not more than 1 inch from the surface of the concrete. Group IV: includes concrete having siliceous aggregates containing a combined total of 60 percent or more of quartz, chert and flint, and tied with No. 5 gage steel wire wound spirally over the column section on a pitch of 8 inches, or equivalent ties.
3. Groupings of aggregates and ties are the same as for structural steel columns protected solidly with concrete, the ties to be placed over the vertical reinforcing bars and the mesh where required, to be placed within 1 inch from the surface of the column. Column A: working loads are assumed as carried by the area of the column inside of the lines circumscribing the reinforcing steel. Column B: working loads are assumed as carried by the gross area of the column.

FIGURE 2.1.5

REINFORCED CONCRETE COLUMNS MINIMUM DIMENSION 16 ″ TO LESS THAN 18 ″

NUMBER OF ASSEMBLIES

10

5

0

3 4 5 6 7 8 9 10

FIRE-RESISTANCE RATING (HOURS)

1 2

0

TABLE 2.1.5
REINFORCED CONCRETE COLUMNS
MINIMUM DIMENSION 16″ TO LESS THAN 18″

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 2.1.5—continued
REINFORCED CONCRETE COLUMNS
MINIMUM DIMENSION 16″ TO LESS THAN 18″

For SI: 1 inch = 25.4 mm, 1 pound per square inch = 0.00689 MPa, 1 pound per square yard = 5.3 N/m [2] .

Notes:

1. Column passed 1-hour fire test.
2. Column passed hose stream test.
3. No reload specified.
4. Column passed 2-hour fire test.
5. Column reloaded successfully after 24 hours.
6. Reinforcing details same as C-16-RC-1.
7. Column passed reload after 72 hours.
8. Group I: includes concrete having calcareous aggregate containing a combined total of not more than 10 percent of quartz, chert and flint for the coarse aggregate. Group II: includes concrete having trap-rock aggregate applied without metal ties and also concrete having cinder, sandstone or granite aggregate, if held in place with wire mesh or expanded metal having not larger than 4-inch mesh, weighing not less than 1.7 lbs/yd [2], placed not more than 1 inch from the surface of the concrete. Group III: includes concrete having cinder, sandstone or granite aggregate tied with No. 5 gage steel wire, wound spirally over the column section on a pitch of 8 inches, or equivalent ties, and concrete having siliceous aggregates containing a combined total of 60 percent or more of quartz, chert and flint, if held in place with wire mesh or expanded metal having not larger than 4-inch mesh, weighing not less than 1.7 lbs/yd [2], placed not more than 1 inch from the surface of the concrete. Group IV: includes concrete having siliceous aggregates containing a combined total of 60 percent or more of quartz, chert and flint, and tied with No. 5 gage steel wire wound spirally over the column section on a pitch of 8 inches, or equivalent ties.
9. Groupings of aggregates and ties are the same as for structural steel columns protected solidly with concrete, the ties to be placed over the vertical reinforcing bars and the mesh where required, to be placed within 1 inch from the surface of the column. Column A: working loads are assumed as carried by the area of the column inside of the lines circumscribing the reinforcing steel. Column B: working loads are assumed as carried by the gross area of the column.

RESOURCE A-72 2025 CALIFORNIA EXISTING BUILDING CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 2.1.6
REINFORCED CONCRETE COLUMNS
MINIMUM DIMENSION 18″ TO LESS THAN 20″

For SI: 1 inch = 25.4 mm, 1 pound per square yard = 5.3 N/m [2] .

Notes :

1. Group I: includes concrete having calcareous aggregate containing a combined total of not more than 10 percent of quartz, chert and flint for the coarse aggregate. Group II: includes concrete having trap-rock aggregate applied without metal ties and also concrete having cinder, sandstone or granite aggregate, if held in place with wire mesh or expanded metal having not larger than 4-inch mesh, weighing not less than 1.7 lbs/yd [2], placed not more than 1 inch from the surface of the concrete. Group III: includes concrete having cinder, sandstone or granite aggregate tied with No. 5 gage steel wire, wound spirally over the column section on a pitch of 8 inches, or equivalent ties, and concrete having siliceous aggregates containing a combined total of 60 percent or more of quartz, chert and flint, if held in place with wire mesh or expanded metal having not larger than 4-inch mesh, weighing not less than 1.7 lbs/yd [2], placed not more than 1 inch from the surface of the concrete. Group IV: includes concrete having siliceous aggregates containing a combined total of 60 percent or more of quartz, chert and flint and, tied with No. 5 gage steel wire wound spirally over the column section on a pitch of 8 inches, or equivalent ties.
2. Groupings of aggregates and ties are the same as for structural steel columns protected solidly with concrete, the ties to be placed over the vertical reinforcing bars and the mesh where required, to be placed within 1 inch from the surface of the column. Column A: working loads are assumed as carried by the area of the column inside of the lines circumscribing the reinforcing steel. Column B: working loads are assumed as carried by the gross area of the column.

eel columns protected solidly with concrete, the ties to be placed over the vertical reinforcing bars and the mesh where required, to be placed within 1 inch from the surface of the column. Column A: working loads are assumed as carried by the area of the column inside of the lines circumscribing the reinforcing steel. Column B: working loads are assumed as carried by the gross area of the column.

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

FIGURE 2.1.7

REINFORCED CONCRETE COLUMNS

MINIMUM DIMENSION 20 ″ TO LESS THAN 22 ″

NUMBER OF ASSEMBLIES

10

5

0

9 10

11 12

0 1 2 3 4 5 6 7 8

FIRE-RESISTANCE RATING (HOURS)

TABLE 2.1.7
REINFORCED CONCRETE COLUMNS
MINIMUM DIMENSION 20″ TO LESS THAN 22″

RESOURCE A-74 2025 CALIFORNIA EXISTING BUILDING CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 2.1.7—continued
REINFORCED CONCRETE COLUMNS
MINIMUM DIMENSION 20″ TO LESS THAN 22″

For SI: 1 inch = 25.4 mm, 1 pound per square yard = 5.3 N/m [2], 1 ton = 8.896 kN.

Notes:

1. Passed 2-hour fire test.

2. Passed hose stream test.

3. Failed during reload at 300 tons.

4. Passed reload after 72 hours.

5. Failure mode—collapse.

6. Group I: includes concrete having calcareous aggregate containing a combined total of not more than 10 percent of quartz, chert and flint for the coarse aggregate. Group II: includes concrete having trap-rock aggregate applied without metal ties and also concrete having cinder, sandstone or granite aggregate, if held in place with wire mesh or expanded metal having not larger than 4-inch mesh, weighing not less than 1.7 lbs/yd [2], placed not more than 1 inch from the surface of the concrete. Group III: includes concrete having cinder, sandstone or granite aggregate tied with No. 5 gage steel wire, wound spirally over the column section on a pitch of 8 inches, or equivalent ties, and concrete having siliceous aggregates containing a combined total of 60 percent or more of quartz, chert and flint, if held in place with wire mesh or expanded metal having not larger than 4-inch mesh, weighing not less than 1.7 lbs/yd [2], placed not more than 1 inch from the surface of the concrete. Group IV: includes concrete having siliceous aggregates containing a combined total of 60 percent or more of quartz, chert and flint, and tied with No. 5 gage steel wire wound spirally over the column section on a pitch of 8 inches, or equivalent ties.

7. Groupings of aggregates and ties are the same as for structural steel columns protected solidly with concrete, the ties to be placed over the vertical reinforcing bars and the mesh where required, to be placed within 1 inch from the surface of the column. Column A: working loads are assumed as carried by the area of the column inside of the lines circumscribing the reinforcing steel. Column B: working loads are assumed as carried by the gross area of the column.

eel columns protected solidly with concrete, the ties to be placed over the vertical reinforcing bars and the mesh where required, to be placed within 1 inch from the surface of the column. Column A: working loads are assumed as carried by the area of the column inside of the lines circumscribing the reinforcing steel. Column B: working loads are assumed as carried by the gross area of the column.

TABLE 2.1.8
HEXAGONAL REINFORCED CONCRETE COLUMNS
MINIMUM DIMENSION 12″ TO LESS THAN 14″

For SI: 1 inch = 25.4 mm, 1 pound per square inch = 0.00689 MPa, 1 ton = 8.896 kN.

Notes:

1. Failure mode—collapse.
2. Test stopped at 1 hour.

TABLE 2.1.9
HEXAGONAL REINFORCED CONCRETE COLUMNS
MINIMUM DIMENSION 14″ TO LESS THAN 16″

For SI: 1 inch = 25.4 mm, 1 pound per square inch = 0.00689 MPa, 1 ton = 8.896 kN.

Notes:

1. Withstood 2-hour fire test.

2. Withstood hose stream test.

3. Withstood reload after 48 hours.

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 2.1.10
HEXAGONAL REINFORCED CONCRETE COLUMNS
MINIMUM DIMENSION—16″ TO LESS THAN 18″

For SI: 1 inch = 25.4 mm, 1 pound per square inch = 0.00689 MPa, 1 ton = 8.896 kN.

Notes:

1. Failure mode—collapse.
2. Failed on furnace removal.

TABLE 2.1.11
HEXAGONAL REINFORCED CONCRETE COLUMNS
MINIMUM DIMENSION—20″ TO LESS THAN 22″

For SI: 1 inch = 25.4 mm, 1 pound per square inch = 0.00689 MPa, 1 ton = 8.896 kN.

Notes:

1. Column collapsed on furnace removal.

2. Passed 2 [1] / 4 -hour fire test.

3. Passed hose stream test.

4. Withstood reload after 48 hours.

TABLE 2.2
ROUND CAST IRON COLUMNS

For SI: 1 inch = 25.4 mm.

RESOURCE A-76 2025 CALIFORNIA EXISTING BUILDING CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

NUMBER OF ASSEMBLIES

10

5

0

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

FIGURE 2.3

STEEL COLUMNS—GYPSUM ENCASEMENTS

0 1 2 3 4 5 6

7 8 9 10

FIRE-RESISTANCE RATING (HOURS)

TABLE 2.3
STEEL COLUMNS—GYPSUM ENCASEMENTS

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 2.3—continued
STEEL COLUMNS—GYPSUM ENCASEMENTS

For SI: 1 inch = 25.4 mm, 1 square inch = 645 mm [2] .

TABLE 2.4
TIMBER COLUMNS MINIMUM DIMENSION

For SI: 1 inch = 25.4 mm, 1 square inch = 645 mm [2] .

Notes:

1. Minimum area: 120 square inches.
2. Type of wood: long leaf pine or Douglas fir.

TABLE 2.5.1.1
STEEL COLUMNS—CONCRETE ENCASEMENTS
MINIMUM DIMENSION LESS THAN 6″

For SI: 1 inch = 25.4 mm, 1 pound per square inch = 0.00689 MPa, 1 ton = 8.896 kN.

Notes:

1. Failure mode—collapse.

RESOURCE A-78 2025 CALIFORNIA EXISTING BUILDING CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 2.5.1.2
STEEL COLUMNS—CONCRETE ENCASEMENTS
6″ TO LESS THAN 8″ THICK

For SI: 1 inch = 25.4 mm, 1 pound per square inch = 0.00689 MPa, 1 ton = 8.896 kN.

Notes:

1. Failure mode—collapse.

FIGURE 2.5.1.3

STEEL COLUMNS—CONCRETE ENCASEMENTS

MINIMUM DIMENSION 8 ″ TO LESS THAN 10 ″

NUMBER OF ASSEMBLIES

10

5

0

0 1 2 3 4 5 6

7 8 9 10

FIRE-RESISTANCE RATING (HOURS)

TABLE 2.5.1.3
STEEL COLUMNS—CONCRETE ENCASEMENTS
MINIMUM DIMENSION 8″ TO LESS THAN 10″

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 2.5.1.3—continued
STEEL COLUMNS—CONCRETE ENCASEMENTS
MINIMUM DIMENSION 8″ TO LESS THAN 10″

For SI: 1 inch = 25.4 mm, 1 pound = 0.004448 kN, 1 pound per square inch = 0.00689 MPa, 1 pound per square yard = 5.3 N/m [2], 1 ton = 8.896 kN.

Notes:

1. Failure mode—collapse.
2. Group I: includes concrete having calcareous aggregate containing a combined total of not more than 10 percent of quartz, chert and flint for the coarse aggregate. Group II: includes concrete having trap-rock aggregate applied without metal ties and also concrete having cinder, sandstone or granite aggregate, if held in place with wire mesh or expanded metal having not larger than 4-inch mesh, weighing not less than 1.7 lbs/yd [2], placed not more than 1 inch from the surface of the concrete. Group III: includes concrete having cinder, sandstone or granite aggregate tied with No. 5 gage steel wire, wound spirally over the column section on a pitch of 8 inches, or equivalent ties, and concrete having siliceous aggregates containing a combined total of 60 percent or more of quartz, chert and flint, if held in place with wire mesh or expanded metal having not larger than 4-inch mesh, weighing not less than 1.7 lbs/yd [2], placed not more than 1 inch from the surface of the concrete. Group IV: includes concrete having siliceous aggregates containing a combined total of 60 percent or more of quartz, chert and flint, and tied with No. 5 gage steel wire wound spirally over the column section on a pitch of 8 inches, or equivalent ties.

RESOURCE A-80 2025 CALIFORNIA EXISTING BUILDING CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

NUMBER OF ASSEMBLIES

10

5

0

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

FIGURE 2.5.1.4 STEEL COLUMNS—CONCRETE ENCASEMENTS MINIMUM DIMENSION 10 ″ TO LESS THAN 12 ″

0 1 2 3 4 5 6 7

8 9 10

FIRE-RESISTANCE RATING (HOURS)

TABLE 2.5.1.4
STEEL COLUMNS—CONCRETE ENCASEMENTS
MINIMUM DIMENSION 10″ TO LESS THAN 12″

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 2.5.1.4—continued
STEEL COLUMNS—CONCRETE ENCASEMENTS
MINIMUM DIMENSION 10″ TO LESS THAN 12″

RESOURCE A-82 2025 CALIFORNIA EXISTING BUILDING CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 2.5.1.4—continued
STEEL COLUMNS—CONCRETE ENCASEMENTS
MINIMUM DIMENSION 10″ TO LESS THAN 12″

For SI: 1 inch = 25.4 mm, 1 pound = 0.004448 kN, 1 pound per square inch = 0.00689 MPa, 1 pound per square yard = 5.3 N/m [2], 1 ton = 8.896 kN.

Notes:

1. Tested under total restraint load to prevent expansion—minimum load 90 tons.

2. Failure mode—collapse.

3. Passed 2-hour fire test (Grade “C,” British).

4. Passed hose stream test.

5. Column tested and passed 3-hour grade fire resistance (British).

6. Column passed 3-hour fire test.

7. Column collapsed during hose stream testing.

8. Column passed 6-hour fire test.

9. Group I: includes concrete having calcareous aggregate containing a combined total of not more than 10 percent of quartz, chert and flint for the coarse aggregate. Group II: includes concrete having trap-rock aggregate applied without metal ties and also concrete having cinder, sandstone or granite aggregate, if held in place with wire mesh or expanded metal having not larger than 4-inch mesh, weighing not less than 1.7 lbs/yd [2], placed not more than 1 inch from the surface of the concrete. Group III: includes concrete having cinder, sandstone or granite aggregate tied with No. 5 gage steel wire, wound spirally over the column section on a pitch of 8 inches, or equivalent ties, and concrete having siliceous aggregates containing a combined total of 60 percent or more of quartz, chert and flint, if held in place with wire mesh or expanded metal having not larger than 4-inch mesh, weighing not less than 1.7 lbs/yd [2], placed not more than 1 inch from the surface of the concrete. Group IV: includes concrete having siliceous aggregates containing a combined total of 60 percent or more of quartz, chert and flint, and tied with No. 5 gage steel wire wound spirally over the column section on a pitch of 8 inches, or equivalent ties.

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

FIGURE 2.5.1.5

STEEL COLUMNS—CONCRETE ENCASEMENTS MINIMUM DIMENSION 12 ″ TO LESS THAN 14 ″

NUMBER OF ASSEMBLIES

10

5

0

0 1 2 3 4 5 6 7

8 9 10

11

FIRE-RESISTANCE RATING (HOURS)

TABLE 2.5.1.5
STEEL COLUMNS—CONCRETE ENCASEMENTS
MINIMUM DIMENSION 12″ TO LESS THAN 14″

RESOURCE A-84 2025 CALIFORNIA EXISTING BUILDING CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 2.5.1.5—continued
STEEL COLUMNS—CONCRETE ENCASEMENTS
MINIMUM DIMENSION 12″ TO LESS THAN 14″

For SI: 1 inch = 25.4 mm, 1 pound = 0.004448 kN, 1 pound per square inch = 0.00689 MPa, 1 pound per square yard = 5.3 N/m [2], 1 ton = 8.896 kN.

Notes:

1. Failure mode—collapse.
2. Group I: includes concrete having calcareous aggregate containing a combined total of not more than 10 percent of quartz, chert and flint for the coarse aggregate. Group II: includes concrete having trap-rock aggregate applied without metal ties and also concrete having cinder, sandstone or granite aggregate, if held in place with wire mesh or expanded metal having not larger than 4-inch mesh, weighing not less than 1.7 lbs/yd [2], placed not more than 1 inch from the surface of the concrete. Group III: includes concrete having cinder, sandstone or granite aggregate tied with No. 5 gage steel wire, wound spirally over the column section on a pitch of 8 inches, or equivalent ties, and concrete having siliceous aggregates containing a combined total of 60 percent or more of quartz, chert and flint, if held in place with wire mesh or expanded metal having not larger than 4-inch mesh, weighing not less than 1.7 lbs/yd [2], placed not more than 1 inch from the surface of the concrete. Group IV: includes concrete having siliceous aggregates containing a combined total of 60 percent or more of quartz, chert and flint, and tied with No. 5 gage steel wire wound spirally over the column section on a pitch of 8 inches, or equivalent ties.

FIGURE 2.5.1.6

STEEL COLUMNS—CONCRETE ENCASEMENTS

MINIMUM DIMENSION 14 ″ TO LESS THAN 16 ″

NUMBER OF ASSEMBLIES

10

5

0

0 1 2 3 4 5 6 7 8

FIRE-RESISTANCE RATING (HOURS)

9 10

11 12

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 2.5.1.6
STEEL COLUMNS—CONCRETE ENCASEMENTS
MINIMUM DIMENSION 14″ TO LESS THAN 16″

For SI: 1 inch = 25.4 mm, 1 pound = 0.004448 kN, 1 pound per square inch = 0.00689 MPa, 1 pound per square yard = 5.3 N/m [2], 1 ton = 8.896 kN.

Notes:

1. Collapse.
2. Group I: includes concrete having calcareous aggregate containing a combined total of not more than 10 percent of quartz, chert and flint for the coarse aggregate. Group II: includes concrete having trap-rock aggregate applied without metal ties and also concrete having cinder, sandstone or granite aggregate, if held in place with wire mesh or expanded metal having not larger than 4-inch mesh, weighing not less than 1.7 lbs/yd [2], placed not more than 1 inch from the surface of the concrete. Group III: includes concrete having cinder, sandstone or granite aggregate tied with No. 5 gage steel wire, wound spirally over the column section on a pitch of 8 inches, or equivalent ties, and concrete having siliceous aggregates containing a combined total of 60 percent or more of quartz, chert and flint, if held in place with wire mesh or expanded metal having not larger than 4-inch mesh, weighing not less than 1.7 lbs/yd [2], placed not more than 1 inch from the surface of the concrete. Group IV: includes concrete having siliceous aggregates containing a combined total of 60 percent or more of quartz, chert and flint, and tied with No. 5 gage steel wire wound spirally over the column section on a pitch of 8 inches, or equivalent ties.

TABLE 2.5.1.7
STEEL COLUMNS—CONCRETE ENCASEMENTS
MINIMUM DIMENSION 16″ TO LESS THAN 18″

For SI: 1 inch = 25.4 mm.

Notes:

1. Group I: includes concrete having calcareous aggregate containing a combined total of not more than 10 percent of quartz, chert and flint for the coarse aggregate. Group II: includes concrete having trap-rock aggregate applied without metal ties and also concrete having cinder, sandstone or granite aggregate, if held in place with wire mesh or expanded metal having not larger than 4-inch mesh, weighing not less than 1.7 lbs/yd [2], placed not more than 1 inch from the surface of the concrete. Group III: includes concrete having cinder, sandstone or granite aggregate tied with No. 5 gage steel wire, wound spirally over the column section on a pitch of 8 inches, or equivalent ties, and concrete having siliceous aggregates containing a combined total of 60 percent or more of quartz, chert and flint, if held in place with wire mesh or expanded metal having not larger than 4-inch mesh, weighing not less than 1.7 lbs/yd [2], placed not more than 1 inch from the surface of the concrete. Group IV: includes concrete having siliceous aggregates containing a combined total of 60 percent or more of quartz, chert and flint, and tied with No. 5 gage steel wire wound spirally over the column section on a pitch of 8 inches, or equivalent ties.

RESOURCE A-86 2025 CALIFORNIA EXISTING BUILDING CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 2.5.2.1
STEEL COLUMNS—BRICK AND BLOCK ENCASEMENTS
MINIMUM DIMENSION 10″ TO LESS THAN 12″

For SI: 1 inch = 25.4 mm, 1 pound = 0.004448 kN, 1 ton = 8.896 kN.

Notes:

1. Failure mode—collapse.

2. Passed 2-hour fire test (Grade “C,” British).

3. Passed hose stream test.

4. Passed reload test.

5. Passed 2-hour fire exposure but collapsed immediately following hose stream test.

TABLE 2.5.2.2
STEEL COLUMNS—BRICK AND BLOCK ENCASEMENTS
MINIMUM DIMENSION 12″ TO LESS THAN 14″

For SI: 1 inch = 25.4 mm, 1 pound = 0.004448 kN, 1 ton = 8.896 kN.

Notes:

1. Failure mode—collapse.

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 2.5.2.3
STEEL COLUMNS—BRICK AND BLOCK ENCASEMENTS
MINIMUM DIMENSION 14″ TO LESS THAN 16″

For SI: 1 inch = 25.4 mm, 1 pound = 0.004448 kN, 1 ton = 8.896 kN.

Notes:

1. Only a nominal load was applied to specimen.
2. Passed 6-hour fire test (Grade “A,” British).
3. Passed (6 minute) hose stream test.
4. Reload not specified.
5. Passed 4-hour fire exposure.
6. Failed by collapse between first and second minute of hose stream exposure.
7. Mode of failure—collapse.

TABLE 2.5.3.1
STEEL COLUMNS—PLASTER ENCASEMENTS
MINIMUM DIMENSION 6″ TO LESS THAN 8″

Notes:

1. Failure mode—collapse.

RESOURCE A-88 2025 CALIFORNIA EXISTING BUILDING CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 2.5.3.2
STEEL COLUMNS—PLASTER ENCASEMENTS
MINIMUM DIMENSION 8″ TO LESS THAN 10″

For SI: 1 inch = 25.4 mm, 1 pound = 0.004448 kN, 1 ton = 8.896 kN.

Notes:

1. Failure mode—collapse.

2. Passed 2 hour fire exposure test (Grade “C,” British).

3. Passed hose stream test.

4. Passed reload test.

TABLE 2.5.4.1
STEEL COLUMNS—MISCELLANEOUS ENCASEMENTS
MINIMUM DIMENSION 6″ TO LESS THAN 8″

For SI: 1 inch = 25.4 mm, 1 pound = 0.004448 kN, 1 ton = 8.896 kN.

Notes:

1. Failure mode—collapse.

TABLE 2.5.4.2
STEEL COLUMNS—MISCELLANEOUS ENCASEMENTS
MINIMUM DIMENSION 8″ TO LESS THAN 10″

For SI: 1 inch = 25.4 mm, 1 pound = 0.004448 kN, 1 ton = 8.896 kN.

Notes:

1. Passed 2-hour fire exposure test.
2. Collapsed during hose stream test.

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 2.5.4.3
STEEL COLUMNS—MISCELLANEOUS ENCASEMENTS
MINIMUM DIMENSION 10″ TO LESS THAN 12″

For SI: 1 inch = 25.4 mm, 1 pound = 0.004448 kN, 1 ton = 8.896 kN.

Notes:

1. Passed 2-hour fire exposure (Grade “C,” British).

2. Passed hose stream test.

3. Passed reload test.

4. Passed 4-hour fire exposure test.

TABLE 2.5.4.4
STEEL COLUMNS—MISCELLANEOUS ENCASEMENTS
MINIMUM DIMENSION 12″ TO LESS THAN 14″

For SI: 1 inch = 25.4 mm, 1 pound = 0.004448 kN, 1 ton = 8.896 kN.

Notes:

1. Passed 4 hour fire exposure (Grade “B,” British).

2. Passed hose stream test.

3. Passed reload test.

RESOURCE A-90 2025 CALIFORNIA EXISTING BUILDING CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

10

5

RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

SECTION III—FLOOR/CEILING ASSEMBLIES

FIGURE 3.1 FLOOR/CEILING ASSEMBLIES—REINFORCED CONCRETE

BER OF The number in each box is
MBLIES keyed to the last number in the
Item Code column in the Table.
For example:
F/C-7-RC-40
49 50
48 42
23 39 40
45 20 33 36
44 46 18 21 34
17 41 16 13 29
43 14 19 10 11 35 28
30 4 12 8 9 26 25 38
5 3 47 1 7 15 2 22 24 27 31 6 32 37

5 6

0

0 1 2 3 4

FIRE-RESISTANCE RATING (HOURS)

TABLE 3.1
FLOOR/CEILING ASSEMBLIES—REINFORCED CONCRETE

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TABLE 3.1—continued
FLOOR/CEILING ASSEMBLIES—REINFORCED CONCRETE

RESOURCE A-92 2025 CALIFORNIA EXISTING BUILDING CODE

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TABLE 3.1—continued
FLOOR/CEILING ASSEMBLIES—REINFORCED CONCRETE

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TABLE 3.1—continued
FLOOR/CEILING ASSEMBLIES—REINFORCED CONCRETE

RESOURCE A-94 2025 CALIFORNIA EXISTING BUILDING CODE

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TABLE 3.1—continued
FLOOR/CEILING ASSEMBLIES—REINFORCED CONCRETE

For SI: 1 inch = 25.4 mm, 1 foot = 305 mm, 1 pound per square inch = 0.00689 MPa, 1 pound per square foot = 47.9 N/m [2] .

Notes:

1. British test.

2. Failure mode—local back face temperature rise.

3. Tested for Grade “C” (2-hour) fire resistance

4. Collapse imminent following hose stream.

5. Failure mode—flame thru.

6. Void formed with explosive force and report.

7. Achieved Grade “B” (4-hour) fire resistance (British).

8. Failure mode—collapse.

9. Test was run to 2 hours, but specimen was partially supported by the furnace at 1 [1] / 4 hours.

10. Failure mode—average back face temperature.

11. Recommended endurance for non-load-bearing performance only.

12. Floor maintained load-bearing ability to 2 hours at which point test was terminated.

13. Test was run to 3 hours at which time failure mode 2 (above) was reached in spite of crack formation at 29 minutes.

14. Tested for Grade “A” (6-hour) fire resistance.

16. Load unspecified.

17. Total assembly thickness 5 [1] / 2 inches. Three-inch thick blocks of molded excelsior bonded with Portland cement used as inserts with 2 [1] / 2 -inch cover (concrete) above blocks and 3 / 4 -inch gypsum plaster below. Nine-inch-wide ribs containing reinforcing steel of unspecified size interrupted 20-inch-wide segments of slab composite (i.e., plaster, excelsior blocks, concrete cover).

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FIGURE 3.2 FLOOR/CEILING ASSEMBLIES—STEEL STRUCTURAL ELEMENTS

10

5

0

0 1 2 3 4

5

FIRE-RESISTANCE RATING (HOURS)

TABLE 3.2
FLOOR/CEILING ASSEMBLIES—STEEL STRUCTURAL ELEMENTS

RESOURCE A-96 2025 CALIFORNIA EXISTING BUILDING CODE

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TABLE 3.2—continued
FLOOR/CEILING ASSEMBLIES—STEEL STRUCTURAL ELEMENTS

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TABLE 3.2—continued
FLOOR/CEILING ASSEMBLIES—STEEL STRUCTURAL ELEMENTS

RESOURCE A-98 2025 CALIFORNIA EXISTING BUILDING CODE

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TABLE 3.2—continued
FLOOR/CEILING ASSEMBLIES—STEEL STRUCTURAL ELEMENTS

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TABLE 3.2—continued
FLOOR/CEILING ASSEMBLIES—STEEL STRUCTURAL ELEMENTS

For SI: 1 inch = 25.4 mm, 1 foot = 305 mm, 1 pound per square inch = 0.00689 MPa, 1 pound per square foot = 47.9 N/m [2] .

Notes:

1. No protective membrane over structural steel.

2. Performance time indicates first endpoint reached; only several tests were continued to points where other failures occurred.

3. Load failure.

4. Thermal failure.

5. This is an estimated time to load-bearing failure. The same joist and deck specimen was used for a later test with different membrane protection.

6. Test stopped at 3 hours to reuse specimen; no endpoint reached.

7. Test stopped at 1 hour to reuse specimen; no endpoint reached.

8. All plaster used = gypsum.

9. Specimen size: 18 feet by 13 [1] / 2 inches. Floor deck base material: [1] / 4 -inch by 18-foot steel plate welded to “I” beams.

10. “I” beams, 24 inches o.c.

11. “I” beams, 48 inches o.c.

12. Apply to open-web joists, pressed steel joists or rolled steel beams, which are not stressed beyond 18,000 lbs/in. [2] in flexure for open-web pressed or light rolled joists, and 20,000 lbs/in. [2] for American standard or heavier rolled beams.

13. Ratio of weight of Portland cement to fine and coarse aggregates combined for floor slabs shall not be less than 1:6 [1] / 2 .

14. Plaster for ceiling shall be applied on metal lath which shall be tied to supports to give the equivalent of single No. 18 gage steel wires 5 inches o.c.

15. Load: maximum fiber stress in steel not to exceed 16,000 psi.

16. Prefabricated units 2 feet wide with length equal to the span, composed of two pieces of No. 18 gage formed steel welded together to give four longitudinal cells.

17. Depth not less than 3 inches and distance between cells not less than 2 inches.

18. Ceiling: metal lath tied to furring channels secured to runner channels hung from cellular steel.

19. Load: rolled steel supporting beams and steel plate base shall not be stressed beyond 20,000 psi in flexure. Formed steel (with wide upper flange) construction shall not be stressed beyond 16,000 psi.

20. Some type of expanded metal or woven wire shall be embedded to prevent cracking in concrete flooring.

21. Ceiling plaster shall be metal lath wired to rods or channels which are clipped or welded to steel construction. Lath shall be no smaller than 18 gage steel wire and not more than 7 inches o.c.

22. The securing rods or channels shall be at least as effective as single [3] / 16 -inch rods with 1-inch of their length bent over the lower flanges of beams with the rods or channels tied to this clip with 14 gage iron wire.

RESOURCE A-100 2025 CALIFORNIA EXISTING BUILDING CODE

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NUMBER OF ASSEMBLIES

15

10

5

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FIGURE 3.3 FLOOR/CEILING ASSEMBLIES—WOOD JOIST

0

0 1 2 3 4

FIRE-RESISTANCE RATING (HOURS)

TABLE 3.3
FLOOR/CEILING ASSEMBLIES—WOOD JOIST

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TABLE 3.3—continued
FLOOR/CEILING ASSEMBLIES—WOOD JOIST

RESOURCE A-102 2025 CALIFORNIA EXISTING BUILDING CODE

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TABLE 3.3—continued
FLOOR/CEILING ASSEMBLIES—WOOD JOIST

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TABLE 3.3—continued
FLOOR/CEILING ASSEMBLIES—WOOD JOIST

For SI: 1 inch = 25.4 mm, 1 foot = 305 mm, 1 pound per square inch = 0.00689 MPa, 1 pound per square foot = 47.9 N/m [2] .

Notes:

1. Thickness indicates thickness of first membrane protection on ceiling surface.
2. Failure mode—flame thru.
3. Failure mode—collapse.
4. No endpoint reached at termination of test.
5. Failure imminent—test terminated.
6. Joist failure—11.5 minutes; flame thru—13 minutes; collapse—24 minutes.
7. Joist failure—17 minutes; flame thru—18 minutes; collapse—33 minutes.
8. Joist failure—18 minutes; flame thru—8 minutes; collapse—30 minutes.
9. Joist failure—12 minutes; flame thru—8 minutes; collapse—22 minutes.
10. Joist failure—11 minutes; flame thru—17 minutes; collapse—27 minutes.
11. Joist failure—17 minutes; flame thru—20 minutes; collapse—43 minutes.
12. Joists: 2-inch by 10-inch southern pine or Douglas fir, No. 1 common or better. Subfloor: [3] / 4 -inch wood sheathing diaphragm of asbestos paper, and finish of tongue-and-groove wood flooring.
13. Loadings: not more than 1,000 psi maximum fiber stress in joists.
14. Perforations in gypsum lath are to be not less than [3] / 4 -inch diameter with one perforation for not more than 16/in. [2] diameter.
15. “Distemper” is a British term for a water-based paint such as white wash or calcimine.

FIGURE 3.4 FLOOR/CEILING ASSEMBLIES—HOLLOW CLAY TILE WITH REINFORCED CONCRETE

NUMBER OF ASSEMBLIES

10

5

0

0 1 2 3 4

FIRE-RESISTANCE RATING (HOURS)

RESOURCE A-104 2025 CALIFORNIA EXISTING BUILDING CODE

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TABLE 3.4
FLOOR/CEILING ASSEMBLIES—HOLLOW CLAY TILE WITH REINFORCED CONCRETE

For SI: 1 inch = 25.4 mm, 1 foot = 305 mm, 1 pound per square inch = 0.00689 MPa, 1 pound per square foot = 47.9 N/m [2] .

Notes:

1. A generalized cross section of this floor type follows:

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TABLE 3.4—continued FLOOR/CEILING ASSEMBLIES—HOLLOW CLAY TILE WITH REINFORCED CONCRETE 2. Failure mode - structural. 3. Plaster: base coat—lime-cement-sand; top coat—gypsum (neat). 4. Failure mode—collapse. 5. Test stopped before any endpoints were reached. 6. A generalized cross section of this floor type follows:

7. Failure mode—thermal; back face temperature rise.

8. Passed hose stream test.

9. Failed hose stream test.

10. Test stopped at 4 hours before any endpoints were reached.

11. A generalized cross section of this floor type follows:

12. Plaster: base coat—retarded hemihydrate gypsum-sand; second coat—neat gypsum.

13. Concrete in Item 7 is Portland cement-based but with crushed brick aggregates, while in Item 8, river sand and river gravels are used with the Portland cement.

14. Load—unspecified.

15. The 12-inch by 12-inch fire-clay tiles were laid end to end in rows spaced 2 [1] / 2 inches or 4 inches apart. The reinforcing steel was placed between these rows and the concrete cast around them and over the tile to form the structural floor.

RESOURCE A-106 2025 CALIFORNIA EXISTING BUILDING CODE

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SECTION IV—BEAMS

TABLE 4.1.1
REINFORCED CONCRETE BEAMS
DEPTH 10″ TO LESS THAN 12″

For SI: 1 inch = 25.4 mm, 1 foot = 305 mm, 1 pound = 0.004448 kN, 1 pound per square inch = 0.00689 MPa, 1 ton = 8.896 kN.

Notes:

1. Load concentrated at mid-span.
2. Achieved 4-hour performance (Class “B,” British).
3. Failure mode—collapse.
4. Achieved 6-hour performance (Class “A,” British).

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RESOURCE A-108 2025 CALIFORNIA EXISTING BUILDING CODE

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

TABLE 4.1.2
REINFORCED CONCRETE BEAMS
DEPTH 12″ TO LESS THAN 14″

For SI: 1 inch = 25.4 mm, 1 foot = 305 mm, 1 pound = 0.004448 kN, 1 pound per square inch = 0.00689 MPa, 1 ton = 8.896 kN.

Notes:

1. Qualified for 2-hour use. British test (Grade “C”) included hose stream and reload at 48 hours.

2. Load concentrated at mid-span.

3. British test.

4. British test—qualified for 6-hour use (Grade “A”).

4" × 6" WIRE MESH OF NO. 13 S.W.G

4" × 6"

2'

8. See Table 4.1.3, Note 5.
9. Hourly rating based upon B-12-RC-2.

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TABLE 4.1.3
REINFORCED CONCRETE BEAMS
DEPTH 14″ TO LESS THAN 16″

For SI: 1 inch = 25.4 mm, 1 foot = 305 mm, 1 pound = 0.004448 kN, 1 pound per square inch = 0.00689 MPa, 1 ton = 8.896 kN.

Notes:

1. Load concentrated at mid-span.
2. Achieved 6-hour fire rating (Grade “A,” British).

5. Section 43.147 of the 1979 edition of the Uniform Building Code Standards provides: “A restrained condition in fire tests, as used in this standard, is one in which expansion at the supports of a load-carrying element resulting from the effects of the fire is resisted by forces external to the element. An unrestrained condition is one in which the load-carrying element is free to expand and rotate at its support. “Restraint in buildings is defined as follows: Floor and roof assemblies and individual beams in buildings shall be considered restrained when the surrounding or supporting structure is capable of resisting the thermal expansion throughout the range of anticipated elevated temperatures. Construction not complying . . . is assumed to be free to rotate and expand and shall be considered as unrestrained. “Restraint may be provided by the lateral stiffness of supports for floor and roof assemblies and intermediate beams forming part of the assembly. In order to develop restraint, connections must adequately transfer thermal thrusts to such supports. The rigidity of adjoining panels or structures shall be considered in assessing the capabilities of a structure to resist thermal expansion.” Because it is difficult to determine whether an existing building’s structural system is capable of providing the required restraint, the lower hourly ratings of a similar but unrestrained assembly have been recommended.
6. Hourly rating based upon Table 4.2.1, Item B-12-RC-2.

TABLE 4.2.1
REINFORCED CONCRETE BEAMS—UNPROTECTED DEPTH
10″ TO LESS THAN 12″

For SI: 1 inch = 25.4 mm, 1 pound = 0.004448 kN, 1 ton = 8.896 kN.

Notes:

1. Concentrated at mid-span.

RESOURCE A-110 2025 CALIFORNIA EXISTING BUILDING CODE

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TABLE 4.2.2
STEEL BEAMS—CONCRETE PROTECTION DEPTH
10″ TO LESS THAN 12″

For SI: 1 inch = 25.4 mm, 1 pound = 0.004448 kN, 1 pound per square inch = 0.00689 MPa, 1 ton = 8.896 kN.

Notes:

1. Load concentrated at mid-span.
2. Specimen 10-foot 3-inch clear span simply supported.
3. Passed Grade “C” fire resistance (British), including hose stream and reload.
4. Specimen 11-foot clear span—restrained.
5. Passed Grade “B” fire resistance (British), including hose stream and reload.
6. See Table 4.1.3, Note 5.
7. Hourly rating based upon B-SC-1.

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SECTION V—DOORS

FIGURE 5.1

RESISTANCE OF DOORS TO FIRE EXPOSURE

NUMBER OF ASSEMBLIES

10

5

0

0 20 40 60 80

EFFECTIVE BARRIER TIME (MINUTES)

TABLE 5.1
RESISTANCE OF DOORS TO FIRE EXPOSURE

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TABLE 5.1—continued
RESISTANCE OF DOORS TO FIRE EXPOSURE

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TABLE 5.1—continued

RESISTANCE OF DOORS TO FIRE EXPOSURE

For SI: 1 inch = 25.4 mm, 1 foot = 305 mm.

Notes:

1. All door frames were of standard lumber construction.

2. Wood door stop protected by asbestos millboard.

3. Wood door stop protected by sheet metal.

4. Door frame protected by sheet metal and weather strip.

5. Surface painted with intumescent coating.

6. Door edge sheet metal protected.

7. Door edge intumescent paint protected.

8. Formal steel frame and door stop.

9. Door opened into furnace at 12 feet.

10. Similar door opened into furnace at 12 feet.

11. The doors reported in these tests represent the type contemporaries used as 20-minute solid-core wood doors. The test results demonstrate the necessity of having wallanchored metal frames with the minimum clearance possible between door, frame and stops. They also indicate the utility of long throw latches and the possible use of intumescent paints to seal doors to frames in event of a fire.

12. Minimum working clearance and good latch closure are absolute necessities for effective containment for all such working door assemblies.

13. Based on British tests.

14. Failure at door-frame interface.

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BIBLIOGRAPHY

1. Central Housing Committee on Research, Design, and Construction; Subcommittee on Fire Resistance Classifications, “Fire-Resistance Classifications of Building Constructions,” Building Materials and Structures, Report BMS 92, National Bureau of Standards, Washington, Oct. 1942. (Available from NTIS No. COM-73-10974)
2. Foster, H. D., Pinkston, E. R., and Ingberg, S. H., “Fire Resistance of Structural Clay Tile Partitions,” Building Materials and Structures, Report BMS 113, National Bureau of Standards, Washington, Oct. 1948.
3. Ryan, J. V., and Bender, E.W., “Fire Endurance of Open-Web Steel-Joist Floors with Concrete Slabs and Gypsum Ceilings,” Building Materials and Structures, Report BMS 141, National Bureau of Standards, Washington, Aug. 1954.
4. Mitchell, N. D., “Fire Tests of Wood-Framed Walls and Partitions with Asbestos-Cement facings,” Building Materials and Structures, Report BMS 123, National Bureau of Standards, Washington, May 1951.
5. Robinson, H. E., Cosgrove, L. A., and Powell, F. J., “Thermal Resistance of Airspace and Fibrous Insulations Bounded by Reflective Surfaces,” Building Materials and Structures, Report BMS 151, National Bureau of Standards, Washington, Nov.

Partitions with Asbestos-Cement facings,” Building Materials and Structures, Report BMS 123, National Bureau of Standards, Washington, May 1951. 5. Robinson, H. E., Cosgrove, L. A., and Powell, F. J., “Thermal Resistance of Airspace and Fibrous Insulations Bounded by Reflective Surfaces,” Building Materials and Structures, Report BMS 151, National Bureau of Standards, Washington, Nov. 1957.

6. Shoub, H., and Ingberg, S. H., “Fire Resistance of Steel Deck Floor Assemblies,” Building Science Series, 11, National Bureau of Standards, Washington, Dec. 1967.
7. Davey, N., and Ashton, L. A., “Investigations on Building Fires, Part V: Fire Tests of Structural Elements,” National Building Studies, Research Paper, No. 12, Dept. of Scientific and Industrial Research (Building Research Station), London, 1953.
8. National Board of Fire Underwriters, Fire Resistance Ratings of Beam, Girder, and Truss Protections, Ceiling Constructions, Column Protections, Floor and Ceiling Constructions, Roof Constructions, Walls and Partitions, New York, April 1959.
9. Mitchell, N.D., Bender, E.D., and Ryan, J.V., “Fire Resistance of Shutters for Moving-Stairway Openings,” Building Materi- als and Structures, Report BMS 129, National Bureau of Standards, Washington, March 1952.
10. National Board of Fire Underwriters, National Building Code; an Ordinance Providing for Fire Limits, and Regulations Governing the Construction, Alteration, Equipment, or Removal of Buildings or Structures, New York, 1949.
11. Department of Scientific and Industrial Research and of the Fire Offices’ Committee, Joint Committee of the Building Research Board, “Fire Gradings of Buildings, Part I: General Principles and Structural Precautions,” Post-War Building Studies, No. 20, Ministry of Works, London, 1946.
12. Lawson, D. I., Webster, C. T., and Ashton, L. A., “Fire Endurance of Timber Beams and Floors,” National Building Studies, Bulletin, No. 13, Dept. of Scientific and Industrial Research and Fire Offices’ Committee (Joint Fire Research Organization), London, 1951.
13. Parker, T. W., Nurse, R. W., and Bessey, G. E., “Investigations on Building Fires. Part I: The Estimation of the Maximum Temperature Attained in Building Fires from Examination of the Debris, and Part II: The Visible Change in Concrete or Mortar Exposed to High Temperatures,” National Building Studies, Technical Paper, No. 4, Dept. of Scientific and Industrial Research (Building Research Station), London, 1950.
14. Bevan, R. C., and Webster, C. T., “Investigations on Building Fires, Part III: Radiation from Building Fires,” National Build- ing Studies, Technical Paper, No. 5, Dept. of Scientific and Industrial Research (Building Research Station), London, 1950.
15. Webster, D. J., and Ashton, L. A., “Investigations on Building Fires, Part IV: Fire Resistance of Timber Doors,” National Building Studies, Technical Paper, No. 6, Dept. of Scientific and Industrial Research (Building Research Station), London,

ational Build-_ ing Studies, Technical Paper, No. 5, Dept. of Scientific and Industrial Research (Building Research Station), London, 1950. 15. Webster, D. J., and Ashton, L. A., “Investigations on Building Fires, Part IV: Fire Resistance of Timber Doors,” National Building Studies, Technical Paper, No. 6, Dept. of Scientific and Industrial Research (Building Research Station), London, 1951.

16. Kidder, F. E., Architects’ and Builders’ Handbook: Data for Architects, Structural Engineers, Contractors, and Draughtsmen, comp. by a Staff of Specialists and H. Parker, editor-in-chief, 18th ed., enl., J. Wiley, New York, 1936.

17. Parker, H., Gay, C. M., and MacGuire, J. W., Materials and Methods of Architectural Construction, 3rd ed., J. Wiley, New York, 1958.

18. Diets, A. G. H., Dwelling House Construction, The MIT Press, Cambridge, 1971.

19. Crosby, E. U., and Fiske, H. A., Handbook of Fire Protection, 5th ed., The Insurance Field Company, Louisville, Ky., 1914.

20. Crosby, E. U., Fiske, H. A., and Forster, H.W., Handbook of Fire Protection, 8th ed., R. S. Moulton, general editor, National Fire Protection Association, Boston, 1936.

21. Kidder, F. E., Building Construction and Superintendence, rev. and enl., by T. Nolan, W. T. Comstock, New York, 1909-1913, 2 vols.

22. National Fire Protection Association, Committee on Fire-Resistive Construction, The Baltimore Conflagration, 2nd ed., Chicago, 1904.

23. Przetak, L., Standard Details for Fire-Resistive Building Construction, McGraw-Hill Book Co., New York, 1977.

24. Hird, D., and Fischl, C. F., “Fire Hazard of Internal Linings,” National Building Studies, Special Report, No. 22, Dept. of Scientific and Industrial Research and Fire Offices’ Committee (Joint Fire Research Organization), London, 1954.

25. Menzel, C. A., Tests of the Fire-Resistance and Strength of Walls Concrete Masonry Units, Portland Cement Association, Chicago, 1934.

26. Hamilton, S. B., “A Short History of the Structural Fire Protection of Buildings Particularly in England,” National Building Studies, Special Report, No. 27, Dept. of Scientific and Industrial Research (Building Research Station), London, 1958.

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

27. Sachs, E. O., and Marsland, E., “The Fire Resistance of Doors and Shutters being Tabulated Results of Fire Tests Conducted by the Committee,” Journal of the British Fire Prevention Committee, No. VII, London, 1912.

28. Egan, M. D., Concepts in Building Firesafety, J. Wiley, New York, 1978.

29. Sachs, E. O., and Marsland, E., “The Fire Resistance of Floors being Tabulated Results of Fire Tests Conducted by the Committee,” Journal of the British Fire Prevention Committee, No. VI, London, 1911.

30. Sachs, E. O., and Marsland, E., “The Fire Resistance of Partitions being Tabulated Results of Fire Tests Conducted by the Committee,” Journal of the British Fire Prevention Committee, No. IX, London, 1914.

31. Ryan, J. V., and Bender, E. W., “Fire Tests of Precast Cellular Concrete Floors and Roofs,” National Bureau of Standards Monograph, 45, Washington, April 1962.

32. Kingberg, S. H., and Foster, H. D., “Fire Resistance of Hollow Load-Bearing Wall Tile,” National Bureau of Standards Research Paper, No. 37, (Reprint from NBS Journal of Research, Vol. 2) Washington, 1929.

33. Hull, W. A., and Ingberg, S. H., “Fire Resistance of Concrete Columns,” Technologic Papers of the Bureau of Standards, No. 272, Vol. 18, Washington, 1925, pp. 635-708.

34. National Board of Fire Underwriters, Fire Resistance Ratings of Less than One Hour, New York, Aug. 1956.

35. Harmathy, T. Z., “Ten Rules of Fire Endurance Rating,” Fire Technology, Vol. 1, May 1965, pp. 93-102.

36. Son, B. C., “Fire Endurance Test on a Steel Tubular Column Protected with Gypsum Board,” National Bureau of Stan- dards, NBSIR, 73-165, Washington, 1973.

37. Galbreath, M., “Fire Tests of Wood Door Assemblies,” Fire Study, No. 36, Div. of Building Research, National Research Council Canada, Ottawa, May 1975.

38. Morris, W. A., “An Investigation into the Fire Resistance of Timber Doors,” Fire Research Note, No. 855, Fire Research Station, Boreham Wood, Jan. 1971.

39. Hall, G. S., “Fire Resistance Tests of Laminated Timber Beams,” Timber Association Research Report, WR/RR/1, High Sycombe, July 1968.

40. Goalwin, D. S., “Fire Resistance of Concrete Floors,” Building Materials and Structures, Report BMS 134, National Bureau of Standards, Washington, Dec. 1952.

41. Mitchell, N. D., and Ryan, J. V., “Fire Tests of Steel Columns Encased with Gypsum Lath and Plaster,” Building Materials and Structures, Report BMS 135, National Bureau of Standards, Washington, April 1953.

42. Ingberg, S. H., “Fire Tests of Brick Walls,” Building Materials and Structures, Report BMS 143, National Bureau of Standards, Washington, Nov. 1954.

43. National Bureau of Standards, “Fire Resistance and Sound-Insulation Ratings for Walls, Partitions, and Floors,” Technical Report on Building Materials, 44, Washington, 1944.

44. Malhotra, H. L., “Fire Resistance of Brick and Block Walls,” Fire Note, No. 6, Ministry of Technology and Fire Offices’ Committee Joint Fire Research Organization, London, HMSO, 1966.

45. Mitchell, N. D., “Fire Tests of Steel Columns Protected with Siliceous Aggregate Concrete,” Building Materials and Struc- tures, Report BMS 124, National Bureau of Standards, Washington, May 1951.

46. Freitag, J. K., Fire Prevention and Fire Protection as Applied to Building Construction; a Handbook of Theory and Practice, 2nd ed., J. Wiley, New York, 1921.

47. Ingberg, S. H., and Mitchell, N. D., “Fire Tests of Wood and Metal-Framed Partition,” Building Materials and Structures, Report BMS 71, National Bureau of Standards, Washington, 1941.

48. Central Housing Committee on Research, Design, and Construction, Subcommittee on Definitions, “A Glossary of Housing Terms,” Building Materials and Structures, Report BMS 91, National Bureau of Standards, Washington, Sept. 1942.

49. Crosby, E. U., Fiske, H. A., and Forster, H.W., Handbook of Fire Protection, 7th ed., D. Van Nostrand Co., New York, 1924.

50. Bird, E. L., and Docking, S. J., Fire in Buildings, A. & C. Black, London, 1949.

51. American Institute of Steel Construction, Fire Resistant Construction in Modern Steel-Framed Buildings, New York, 1959.

52. Central Dockyard Laboratory, “Fire Retardant Paint Tests—a Critical Review,” CDL Technical Memorandum , No. P87/73, H. M. Naval Base, Portsmouth, Dec. 1973.

trand Co., New York, 1924. 50. Bird, E. L., and Docking, S. J., Fire in Buildings, A. & C. Black, London, 1949. 51. American Institute of Steel Construction, Fire Resistant Construction in Modern Steel-Framed Buildings, New York, 1959. 52. Central Dockyard Laboratory, “Fire Retardant Paint Tests—a Critical Review,” CDL Technical Memorandum , No. P87/73, H. M. Naval Base, Portsmouth, Dec. 1973.

53. Malhotra, H. L., “Fire Resistance of Structural Concrete Beams,” Fire Research Note, No. 741, Fire Research Station, Borehamwood, May 1969.

54. Abrams, M. S., and Gustaferro, A. H., “Fire Tests of Poke-Thru Assemblies,” Research and Development Bulletin, 1481-1, Portland Cement Association, Skokie, 1971.

55. Bullen, M. L., “A Note on the Relationship between Scale Fire Experiments and Standard Test Results,” Building Research Establishment Note, N51/75, Borehamwood, May 1975.

56. The America Fore Group of Insurance Companies, Research Department, Some Characteristic Fires in Fire Resistive Build- ings, Selected from twenty years record in the files of the N.F.P.A. “Quarterly,” New York, c. 1933.

57. Spiegelhalter, F., “Guide to Design of Cavity Barriers and Fire Stops,” Current Paper, CP 7/77, Building Research Establishment, Borehamwood, Feb. 1977.

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

58. Wardle, T. M. “Notes on the Fire Resistance of Heavy Timber Construction,” Information Series, No. 53, New Zealand Forest Service, Wellington, 1966.
59. Fisher, R. W., and Smart, P. M. T., “Results of Fire Resistance Tests on Elements of Building Construction,” Building Research Establishment Report, G R6, London, HMSO, 1975.
60. Serex, E. R., “Fire Resistance of Alta Bates Gypsum Block Non-Load Bearing Wall,” Report to Alta Bates Community Hospital, Structural Research Laboratory Report, ES-7000, University of Calif., Berkeley, 1969.
61. Thomas, F. G., and Webster, C. T., “Investigations on Building Fires, Part VI: The Fire Resistance of Reinforced Concrete Columns,” National Building Studies, Research Paper, No. 18, Dept. of Scientific and Industrial Research (Building Research Station), London, HMSO, 1953.

Alta Bates Community Hospital, Structural Research Laboratory Report, ES-7000, University of Calif., Berkeley, 1969. 61. Thomas, F. G., and Webster, C. T., “Investigations on Building Fires, Part VI: The Fire Resistance of Reinforced Concrete Columns,” National Building Studies, Research Paper, No. 18, Dept. of Scientific and Industrial Research (Building Research Station), London, HMSO, 1953.

62. Building Research Establishment, “Timber Fire Doors,” Digest, 220, Borehamwood, Nov. 1978.

63. Massachusetts State Building Code; Recommended Provisions, Article 22: Repairs, Alterations, Additions, and Change of Use of Existing Buildings, Boston, Oct. 23, 1978.

64. Freitag, J. K., Architectural Engineering; with Especial Reference to High Building Construction, Including Many Examples of Prominent Office Buildings, 2nd ed., rewritten, J. Wiley, New York, 1906.

65. Architectural Record, Sweet’s Indexed Catalogue of Building Construction for the Year 1906, New York, 1906.

66. Dept. of Commerce, Building Code Committee, “Recommended Minimum Requirements for Fire Resistance in Buildings,” Building and Housing, No. 14, National Bureau of Standards, Washington, 1931.

67. British Standards Institution, “Fire Tests on Building Materials and Structures,” British Standards, 476, Pt. 1, London,

69. Lonberg-Holm, K., “Glass,” The Architectural Record, Oct. 1930, pp. 345-357.

70. Structural Clay Products Institute, “Fire Resistance,” Technical Notes on Brick and Tile Construction, 16 rev., Washington,

72. Ramsey, C. G., and Sleeper, H. R., Architectural Graphic Standards for Architects, Engineers, Decorators, Builders, and Draftsmen, 3rd ed., J. Wiley, New York, 1941.

73. Underwriters’ Laboratories, Fire Protection Equipment List, Chicago, Jan. 1957.

74. Underwriters’ Laboratories, Fire Resistance Directory; with Hourly Ratings for Beams, Columns, Floors, Roofs, Walls, and Partitions, Chicago, Jan. 1977.

75. Mitchell, N. D., “Fire Tests of Gunite Slabs and Partitions,” Building Materials and Structures, Report BMS 131, National Bureau of Standards, Washington, May 1952.

76. Woolson, I. H., and Miller, R. P., “Fire Tests of Floors in the United States,” Proceedings International Association for Test- ing Materials, VIth Congress, New York, 1912, Section C, pp. 36-41.

77. Underwriters’ Laboratories, “An Investigation of the Effects of Fire Exposure upon Hollow Concrete Building Units, Conducted for American Concrete Institute, Concrete Products Association, Portland Cement Association, Joint Submittors,” Retardant Report, No. 1555, Chicago, May 1924.

78. Dept. of Scientific & Industrial Research and of the Fire Offices’ Committee, Joint Committee of the Building Research Board, “Fire Gradings of Buildings. Part IV: Chimneys and Flues,” Post-War Building Studies, No. 29, London, HMSO, 1952.

79. National Research Council of Canada. Associate Committee on the National Building Code, Fire Performance Ratings, Suppl. No. 2 to the National Building Code of Canada, Ottawa, 1965.

80. Associated Factory Mutual Fire Insurance Companies, The National Board of Fire Underwriters, and the Bureau of Standards, Fire Tests of Building Columns; an Experimental Investigation of the Resistance of Columns, Loaded and Exposed to Fire or to Fire and Water, with Record of Characteristic Effects, Jointly Conducted at Underwriters. Laboratories, Chicago, 1917-19.

f Canada, Ottawa, 1965. 78. Associated Factory Mutual Fire Insurance Companies, The National Board of Fire Underwriters, and the Bureau of Standards, Fire Tests of Building Columns; an Experimental Investigation of the Resistance of Columns, Loaded and Exposed to Fire or to Fire and Water, with Record of Characteristic Effects, Jointly Conducted at Underwriters. Laboratories, Chicago, 1917-19.

79. Malhotra, H. L., “Effect of Age on the Fire Resistance of Reinforced Concrete Columns,” Fire Research Memorandum, No. 1, Fire Research Station, Borehamwood, April 1970.
80. Bond, H., ed., Research on Fire; a Description of the Facilities, Personnel and Management of Agencies Engaged in Research on Fire, a Staff Report, National Fire Protection Association, Boston, 1957.
81. California State Historical Building Code, Draft, 1978.
82. Fisher, F. L., et al., “A Study of Potential Flashover Fires in Wheeler Hall and the Results from a Full Scale Fire Test of a Modified Wheeler Hall Door Assembly,” Fire Research Laboratory Report, UCX 77-3; UCX-2480, University of Calif., Dept. of Civil Eng., Berkeley, 1977.
83. Freitag, J. K., The Fireproofing of Steel Buildings, 1st ed., J. Wiley, New York, 1906.
84. Gross, D., “Field Burnout Tests of Apartment Dwellings Units,” Building Science Series, 10, National Bureau of Standards, Washington, 1967.
85. Dunlap, M. E., and Cartwright, F. P., “Standard Fire Tests for Combustible Building Materials,” Proceedings of the Ameri- can Society for Testing Materials, vol. 27, Philadelphia, 1927, pp. 534-546.
86. Menzel, C. A., “Tests of the Fire Resistance and Stability of Walls of Concrete Masonry Units,” Proceedings of the American Society for Testing Materials, vol. 31, Philadelphia, 1931, pp. 607-660.

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

87. Steiner, A. J., “Method of Fire-Hazard Classification of Building Materials,” Bulletin of the American Society for Testing and Materials, March 1943, Philadelphia, 1943, pp. 19-22.

88. Heselden, A. J. M., Smith, P. G., and Theobald, C. R., “Fires in a Large Compartment Containing Structural Steelwork; Detailed Measurements of Fire Behavior,” Fire Research Note, No. 646, Fire Research Station, Borehamwood, Dec. 1966.

89. Ministry of Technology and Fire Offices’ Committee Joint Fire Research Organization, “Fire and Structural Use of Timber in Buildings; Proceedings of the Symposium Held at the Fire Research Station, Borehamwood, Herts on 25th October, 1967,” Symposium, No. 3, London, HMSO, 1970.

90. Shoub, H., and Gross, D., “Doors as Barriers to Fire and Smoke,” Building Science Series, 3, National Bureau of Standards, Washington, 1966.

91. Ingberg, S. H., “The Fire Resistance of Gypsum Partitions,” Proceedings of the American Society for Testing and Materials, vol. 25, Philadelphia, 1925, pp. 299-314.

92. Ingberg, S.H., “Influence of Mineral Composition of Aggregates on Fire Resistance of Concrete,” Proceedings of the Ameri- can Society for Testing and Materials, vol. 29, Philadelphia, 1929, pp. 824-829.

93. Ingberg, S. H., “The Fire Resistive Properties of Gypsum,” Proceedings of the American Society for Testing and Materials, vol. 23, Philadelphia, 1923, pp. 254-256.

94. Gottschalk, F.W., “Some Factors in the Interpretation of Small-Scale Tests for Fire-Retardant Wood,” Bulletin of the Amer- ican Society for Testing and Materials, October 1945, pp. 40-43.

95. Ministry of Technology and Fire Offices’ Committee Joint Fire Research Organization, “Behaviour of Structural Steel in Fire; Proceedings of the Symposium Held at the Fire Research Station Borehamwood, Herts on 24th January, 1967,” Symposium, No. 2, London, HMSO, 1968.

96. Gustaferro, A. H., and Martin, L. D., Design for Fire Resistance of Pre-cast Concrete, prep. for the Prestressed Concrete Institute Fire Committee, 1st ed., Chicago, PCI, 1977.

97. “The Fire Endurance of Concrete; a Special Issue,” Concrete Construction, vol. 18, no. 8, Aug. 1974, pp. 345-440.

98. The British Constructional Steelwork Association, “Modern Fire Protection for Structural Steelwork,” Publication, No. FPl, London, 1961.

99. Underwriters’ Laboratories, “Fire Hazard Classification of Building Materials,” Bulletin, No. 32, Sept. 1944, Chicago, 1959.

100. Central Housing Committee on Research, Design, and Construction, Subcommittee on Building Codes, “Recommended Building Code Requirements for New Dwelling Construction with Special Reference to War Housing; Report,” Building Materials and Structures, Report BMS 88, National Bureau of Standards, Washington, Sept. 1942.

101. De Coppet Bergh, D., Safe Building Construction; a Treatise Giving in Simplest Forms Possible Practical and Theoretical Rules and Formulae Used in Construction of Buildings and General Instruction, new ed., thoroughly rev. Macmillan Co., New York, 1908.

ence to War Housing; Report,” Building Materials and Structures, Report BMS 88, National Bureau of Standards, Washington, Sept. 1942. 101. De Coppet Bergh, D., Safe Building Construction; a Treatise Giving in Simplest Forms Possible Practical and Theoretical Rules and Formulae Used in Construction of Buildings and General Instruction, new ed., thoroughly rev. Macmillan Co., New York, 1908.

102. Cyclopedia of Fire Prevention and Insurance; a General Reference Work on Fire and Fire Losses, Fireproof Construction, Building Inspection..., prep. by architects, engineers, underwriters and practical insurance men. American School of Correspondence, Chicago, 1912.

103. Setchkin, N. P., and Ingberg, S. H., “Test Criterion for an Incombustible Material,” Proceedings of the American Society for Testing Materials, vol. 45, Philadelphia, 1945, pp. 866-877.

104. Underwriters’ Laboratories, “Report on Fire Hazard Classification of Various Species of Lumber,” Retardant, 3365, Chicago, 1952.

105. Steingiser, S., “A Philosophy of Fire Testing,” Journal of Fire & Flammability, vol. 3, July 1972, pp. 238-253.

106. Yuill, C. H., Bauerschlag, W. H., and Smith, H. M., “An Evaluation of the Comparative Performance of 2.4.1 Plywood and Two-Inch Lumber Roof Decking under Equivalent Fire Exposure,” Fire Protection Section, Final Report, Project No. 717A-3211, Southwest Research Institute, Dept. of Structural Research, San Antonio, Dec. 1962.

107. Ashton, L. A., and Smart, P.M. T., Sponsored Fire-Resistance Tests on Structural Elements, London, Dept. of Scientific and Industrial Research and Fire Offices. Committee, London, 1960.

108. Butcher, E. G., Chitty, T. B., and Ashton, L. A., “The Temperature Attained by Steel in Building Fires,” Fire Research Techni- cal Paper, No. 15, Ministry of Technology and Fire Offices. Committee, Joint Fire Research Organization, London, HMSO,

110. Dept. of the Environment and Fire Offices’ Committee, Joint Fire Research Organization, “Fire-Resistance Requirements for Buildings—a New Approach; Proceedings of the Symposium Held at the Connaught Rooms, London, 28 September 1971,” Symposium, No. 5, London, HMSO, 1973.

111. Langdon Thomas, G. J., “Roofs and Fire,” Fire Note, No. 3, Dept. of Scientific and Industrial Research and Fire Offices’ Committee, Joint Fire Research Organization, London, HMSO, 1963.

112. National Fire Protection Association and the National Board of Fire Underwriters, Report on Fire in the Edison Phonograph Works, Thomas A. Edison, Inc., West Orange, N.J., December 9, 1914, Boston, 1915.

113. Thompson, J. P., Fire Resistance of Reinforced Concrete Floors, Portland Cement Association, Chicago, 1963.

114. Forest Products Laboratory, “Fire Resistance Tests of Plywood Covered Wall Panels,” Information reviewed and reaffirmed, Forest Service Report, No. 1257, Madison, April 1961.

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

114. Forest Products Laboratory, “Charring Rate of Selected Woods—Transverse to Grain,” Forest Service Research Paper, FLP 69, Madison, April 1967.

115. Bird, G. I., “Protection of Structural Steel Against Fire,” Fire Note, No. 2, Dept. of Scientific and Industrial Research and Fire Offices’ Committee, Joint Fire Research Organization, London, HMSO, 1961.

116. Robinson, W. C., The Parker Building Fire, Underwriters’ Laboratories, Chicago, c. 1908.

117. Ferris, J. E., “Fire Hazards of Combustible Wallboards,” Commonwealth Experimental Building Station Special Report, No. 18, Sydney, Oct. 1955.

118. Markwardt, L. J., Bruce, H. D., and Freas, A. D., “Brief Description of Some Fire-Test Methods Used for Wood and WoodBased Materials,” Forest Service Report, No. 1976, Forest Products Laboratory, Madison, 1976.

119. Foster, H. D., Pinkston, E. R., and Ingberg, S. H., “Fire Resistance of Walls of Gravel-Aggregate Concrete Masonry Units,” Building Materials and Structures, Report, BMS 120, National Bureau of Standards, Washington, March 1951.

120. Foster, H. D., Pinkston, E.R., and Ingberg, S. H., “Fire Resistance of Walls of Lightweight-Aggregate Concrete Masonry Units,” Building Materials and Structures, Report BMS 117, National Bureau of Standards, Washington, May 1950.

121. Structural Clay Products Institute, “Structural Clay Tile Fireproofing,” Technical Notes on Brick & Tile Construction, vol. 1, no. 11, San Francisco, Nov. 1950.

122. Structural Clay Products Institute, “Fire Resistance Ratings of Clay Masonry Walls—I,” Technical Notes on Brick & Tile Construction, vol. 3, no. 12, San Francisco, Dec. 1952.

123. Structural Clay Products Institute, “Estimating the Fire Resistance of Clay Masonry Walls—II,” Technical Notes on Brick & Tile Construction, vol. 4, no. 1, San Francisco, Jan. 1953.

124. Building Research Station, “Fire: Materials and Structures,” Digest, No. 106, London, HMSO, 1958.

125. Mitchell, N. D., “Fire Hazard Tests with Masonry Chimneys,” NFPA Publication, No. Q-43-7, Boston, Oct. 1949.

126. Clinton Wire Cloth Company, Some Test Data on Fireproof Floor Construction Relating to Cinder Concrete, Terra Cotta and Gypsum, Clinton, 1913.

127. Structural Engineers Association of Southern California, Fire Ratings Subcommittee, “Fire Ratings, a Report,” part of Annual Report, Los Angeles, 1962, pp. 30-38.

128. Lawson, D. I., Fox, L. L., and Webster, C. T., “The Heating of Panels by Flue Pipes,” Fire Research, Special Report, No. 1, Dept. of Scientific and Industrial Research and Fire Offices’ Committee, London, HMSO, 1952.

129. Forest Products Laboratory, “Fire Resistance of Wood Construction,” excerpt from “Wood Handbook—Basic Information on Wood as a Material of Construction with Data for its Use in Design and Specification,” Dept. of Agriculture Handbook, No. 72, Washington, 1955, pp. 337-350.

130. Goalwin, D. S., “Properties of Cavity Walls,” Building Materials and Structures, Report BMS 136, National Bureau of Standards, Washington, May 1953.

131. Humphrey, R. L., “The Fire-Resistive Properties of Various Building Materials,” Geological Survey Bulletin, 370, Washington, 1909.

Use in Design and Specification,” Dept. of Agriculture Handbook, No. 72, Washington, 1955, pp. 337-350. 130. Goalwin, D. S., “Properties of Cavity Walls,” Building Materials and Structures, Report BMS 136, National Bureau of Standards, Washington, May 1953. 131. Humphrey, R. L., “The Fire-Resistive Properties of Various Building Materials,” Geological Survey Bulletin, 370, Washington, 1909.

132. National Lumber Manufacturers Association, “Comparative Fire Test on Wood and Steel Joists,” Technical Report, No. 1, Washington, 1961.

133. National Lumber Manufacturers Association, “Comparative Fire Test of Timber and Steel Beams,” Technical Report, No. 3, Washington, 1963.

134. Malhotra, H. L., and Morris, W. A., “Tests on Roof Construction Subjected to External Fire,” Fire Note, No. 4, Dept. of Scientific and Industrial Research and Fire Offices’ Committee, Joint Fire Research Organization, London, HMSO, 1963.

135. Brown, C. R., “Fire Tests of Treated and Untreated Wood Partitions,” Research Paper, RP 1076, part of Journal of Research of the National Bureau of Standards, vol. 20, Washington, Feb. 1938, pp. 217-237.

136. Underwriters’ Laboratories, “Report on Investigation of Fire Resistance of Wood Lath and Lime Plaster Interior Finish,” Publication, SP. 1.230, Chicago, Nov. 1922.

137. Underwriters’ Laboratories, “Report on Interior Building Construction Consisting of Metal Lath and Gypsum Plaster on Wood Supports,” Retardant, No. 1355, Chicago, 1922.

138. Underwriters’ Laboratories, “An Investigation of the Effects of Fire Exposure upon Hollow Concrete Building Units,” Retardant, No. 1555, Chicago, May 1924.

139. Moran, T. H., “Comparative Fire Resistance Ratings of Douglas Fir Plywood,” Douglas Fir Plywood Association Laboratory Bulletin, 57-A, Tacoma, 1957.

140. Gage Babcock & Association, “The Performance of Fire-Protective Materials under Varying Conditions of Fire Severity,” Report 6924, Chicago, 1969.

141. International Conference of Building Officials, Uniform Building Code (1979 ed.), Whittier, CA, 1979.

142. Babrauskas, V., and Williamson, R. B., “The Historical Basis of Fire Resistance Testing, Part I and Part II,” Fire Technology, vol. 14, no. 3 & 4, Aug. & Nov. 1978, pp. 184-194, 205, 304-316.

143. Underwriters’ Laboratories, “Fire Tests of Building Construction and Materials,” 8th ed., Standard for Safety, UL263, Chicago, 1971.

144. Hold, H. G., Fire Protection in Buildings, Crosby, Lockwood, London, 1913.

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RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

145. Kollbrunner, C. F., “Steel Buildings and Fire Protection in Europe,” Journal of the Structural Division, ASCE, vol. 85, no. ST9, Proc. Paper 2264, Nov. 1959, pp. 125-149.

146. Smith, P., “Investigation and Repair of Damage to Concrete Caused by Formwork and Falsework Fire,” Journal of the American Concrete Institute, vol. 60, Title no. 60-66, Nov. 1963, pp. 1535-1566.

147. “Repair of Fire Damage,” 3 parts, Concrete Construction, March-May, 1972.

148. National Fire Protection Association, National Fire Codes; a Compilation of NFPA Codes, Standards, Recommended Prac- tices and Manuals, 16 vols., Boston, 1978.

149. Ingberg, S. H. “Tests of Severity of Building Fires,” NFPA Quarterly, vol. 22, no. 1, July 1928, pp. 43-61.

150. Underwriters’ Laboratories, “Fire Exposure Tests of Ordinary Wood Doors,” Bulletin of Research, no. 6, Dec. 1938, Chicago, 1942.

151. Parson, H., “The Tall Building under Test of Fire,” Red Book, no. 17, British Fire Prevention Committee, London, 1899.

152. Sachs, E. O., “The British Fire Prevention Committee Testing Station,” Red Book, no. 13, British Fire Prevention Committee, London, 1899.

153. Sachs, E. O., “Fire Tests with Unprotected Columns,” Red Book, no. 11, British Fire Prevention Committee, London, 1899.

154. British Fire Prevention Committee, “Fire Tests with Floors a Floor by the Expended Metal Company,” Red Book, no. 14, London, 1899.

155. Engineering News, vol. 56, Aug. 9, 1906, pp. 135-140.

156. Engineering News, vol. 36, Aug. 6, 1896, pp. 92-94.

157. Bauschinger, J., Mittheilungen de Mech.-Tech. Lab. der K. Tech. Hochschule, Müchen, vol. 12, 1885.

158. Engineering News, vol. 46, Dec. 26, 1901, pp. 482-486, 489-490.

159. The American Architect and Building News, vol. 31, March 28, 1891, pp. 195-201.

160. British Fire Prevention Committee, First International Fire Prevention Congress, Official Congress Report, London, 1903.

161. American Society for Testing Materials, Standard Specifications for Fire Tests of Materials and Construction (C19-18), Philadelphia, 1918.

162. International Organization for Standardization, Fire Resistance Tests on Elements of Building Construction (R834), London,

164. Engineering Record, vol. 35, Jan. 2, 1897, pp. 93-94; May 29, 1897, pp. 558-560; vol. 36, Sept. 18, 1897, pp. 337-340; Sept. 25, 1897, pp. 359-363; Oct. 2, 1897, pp. 382-387; Oct. 9, 1897, pp. 402-405.

165. Babrauskas, Vytenis, “Fire Endurance in Buildings,” PhD Thesis. Fire Research Group, Report, No. UCB FRG 76-16, University of California, Berkeley, Nov. 1976.

166. The Institution of Structural Engineers and The Concrete Society, Fire Resistance of Concrete Structures, London, Aug.

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Accessibility 1.8.2.1.2, 1.9.1, 104.2.4, 306, 801.1, 901.2, 1101.2, 1508, Appendix B Additions Chapter 11, 101.2, 101.3, 101.4, 104.3, 104.3.1, 104.2.4.1, 106.2.3, 109.3.3, 113.2, 115.5, 202, 301.1, 301.3, 302.2, 302.2.1, 303.2, 304.1, 304.2, 307.1, 308.1, 309, 501.1, 502, 601.1, 606, 1301.1, 1301.1.1, 1302.1, 1302.1.3, 1303.1, 1304.1.1, 1304.1.3, 1501.3, 1505.2 Administration Chapter 1 Alterations Chapter 7, Chapter 8, Chapter 9, 101.2, 101.3, 101.4, 101.6, 104.3, 104.3.1, 104.3.2, 104.2.4.1, 105.1.1, 105.1.2, 105.2.2, 105.2.3, 106.2.3, 106.2.6, 108.5, 110.2, 113.2, 115.5, 202, 301.1, 301.3, 302.2, 302.2.1, 302.4, 304, 307.1, 308.1, 309.1, 501.1, 501.1.1, 502.1, 502.3, 502.4, 503, 504.1, 601.1, 602, 603, 604, 1101.3, 1103.1, 1103.2, 1301.1, 1301.1.1, 1302.1, 1302.1.4, 1302.1.6, 1303.1, 1304.1.1, 1304.1.3, 1307.1.1, 1401.2, 1501.3, 1504.1, 1505.2, A105.2, A304.1.1, A402.1, A403.2 Level 1 Chapter 7, 104.3.2, 602, 603.2, 604.2, 801.2 Level 2 Chapter 8, 106.2.3, 505.2, 603 Level 3 Chapter 9, 106.2.3, 604, 1011.4 Alternative Materials, Design and Methods of Construction 104.2.3 Ambulatory Care Facility 202, 302.2.1, 406.1.2, 408.3, 501.3, 503.15, 503.17, 804.4,

902.3

Appeals 104.8, 112, 116.6 Approved 202 Approved Agency A304.2.6, 104.2.3.6.1, 202 Archaic Materials and Assemblies

Resource A

Architect (see Registered Design Professional) Area (see Building) Automatic Sprinkler System 110.2, 501.2, 504.5, 802.2.1, 802.6, 803.1.1, 803.2, 804.5.1.1, Table 804.5.1.1(1), 804.5.1.2.1, 804.5.1.2.2, 804.7.1, 804.8, 904.1, 1011.2.1, 1011.6.1, 1011.6.1.1, 1011.7.3, 1011.8.3, 1305.1.1, Table 1305.2.9, 1305.2.10.1, 1305.2.17, 1305.2.17.1, Table 1305.2.17, 1305.2.19, Table 1305.2.19, 1507

Board of Appeals 104.8, 112, Appendix D Building Area 503.5, 503.7, 503.8, 503.9, 503.10, 503.11, 503.16, 503.18, 506.5.2, 506.5.3, 506.6, 603.1, 604.1, 1006.2, 1006.3, 1011.6, 1011.6.1, 1011.6.1.1, 1011.6.2, Table 1011.6, 1102, 1302.1.3, 1305.2.2 Dangerous 104.4, 114.1, 117.1, 202, 302.1 Height 202, 502.1, 804.4.1.1, 1011.6, Table 1011.6, 1011.7.1, 1011.7.3, 1102, 1302.1.3, 1305.2.1, Table 1306.1, A301.2 Historic Chapter 12, 202, 401.1, 501.1, 507, 601.1, 607, 701.1, 1301.1, B101 Relocatable 202, 1401.1 Relocated Chapter 14, 301.4

INDEX

Relocation of 101.2, 101.3, 101.4, 104.3, 301.1 Unsafe 104.4, 115, 116, 117.1, 202

Carbon Monoxide 308 Carpeting 105.2, 702.2 Ceiling 702.1, 801.4, 802.2.1, 802.4, 903.2.1, 1011.3, 1011.5.1, 1305.2.3.3, A105.3, A113.1 Certificate of Occupancy 110, 506.2, 1001.2,

1001.3 Change of Occupancy Chapter 10, 101.2, 101.3, 101.4, 104.3, 104.3.2, 106.2.6, 110.1, 115.5, 202, 301.1, 301.3, 307.1, 308.1, 501.1, 505.3, 506, 601.1, 605, 702.5, 1301.1, 1302.1, 1302.1.6, 1304.1.1, 1304.1.3, 1305.2.17, 1307.1.1, 1401.2, B101.2, B101.3, B101.4, C101.1, C201.1 Change of Use 202 Classroom Acoustics 502.6, 503.16, 506.6, 903.4, 1011.4, 1101.4 Code Official Chapter 1, 202, 301.3, 302.1, 302.3, 303.2.1, 304.2, 405.2.3.1, 501.2, 506.1, 506.1.1, 802.6, 804.2, 1001.2, 1011.5.1, 1303.1, 1303.1.1, 1304.1.2, 1304.1.3, 1402.7, 1501.6.7, 1509.1, A102.2, A107.1, A108.1, A113.7, A205.3.2, A301.1, A301.2, A301.3, A302.1, A303.1, A304.2.1, A304.2.2, A304.2.3, Table A304.2.3(1), A304.2.3(2), Table A304.2.3(2), A304.5, A403.8, A403.9.3.2, A404.1, A405.3, A405.3.2 Compartmentation 1305.2.3, Table 1305.2.3, 1305.2.20, Table 1305.2.20, Table

1306.1 Compliance Methods Chapter 3 Performance compliance method Chapter 13, 301.3.3 Prescriptive compliance method Chapter 5, 301.3.1 Work area compliance method Chapter 6, Chapter 7, Chapter 8, Chapter 9, Chapter 10, Chapter 11, 301.3.2

Conflict 102.1, 102.4.1, 102.4.2, 104.2.4.1, 113.1, 302.2, 1302.1.2 Construction Documents 104.3, 105.3, 105.3.1, 105.4, 106, 113.4, 202, 601.2, A105.4, A205.3, A301.1, A406, A407.1 Construction Safeguards 101.5, Chapter 15 Accessibility 1511 Adjoining property 1505 Automatic sprinklers 1510 Fire extinguishers 1507 Means of egress 1508 Owner’s responsibilities 1502 Protection of pedestrians 1504 Sanitary 1503 Standpipes 1509 Water supply 1512 Corridor

Dead-end 801.4, 804.8, 1011.5.1, 1305.2.12, 1305.2.12.1, Table 1306.1 Doors 804.7.1, 1011.5.1 Exit access 801.4, 802.2.1, 802.4, 802.4.1, 901.2, 1011.8.2 Openings 804.7, 804.7.1, 804.7.2, 804.7.3, 804.7.3.1, 804.7.4, 1011.5.1,

1011.8.2

Projections 704.1.1 Rating 803.1.1, 1011.5.1, 1305.2.5, 1305.2.5.1, Table 1305.2.5, Table

1306.1

Dangerous Nonstructural 115.1, 116.1 Structural 104.4, 114.1, 117.1, 202,

302.1

Deferred Submittal 106.3.4, 106.6, 202 Definitions 202 Demolition 101.5, 104.3, 106.2.6, 108.5, 113.2, 115.5, 117, 1501.6, 1501.6.1, 1501.7, 1502.1, 1503.1, 1504.1, 1505.2 Department of Building Safety 104.2.4, 105.3, 109.3.8 Disproportionate Earthquake Damage 202, 405.2.2, 502.2

Egress (see Means of Egress) Electrical A102.1, 105.1, 105.1.1, 105.2, 108.3, 109.3.4, 202, 406, 801.3, 801.4, 806, 1007, 1101.2 Elevator 905.4, 1011.8.3, 1102.2, 1305.2.14, 1305.2.14.1, Table 1305.2.14, Table 1306.1 Emergency Escape and Rescue Openings 202, 505, 506.4, 702.4, 702.5, 702.5.1, 702.6 Emergency Power 804.6.5, 1305.2.15.1 Energy 302.2, 702.7, 708, 809, 907, 1104 Engineer (see Registered Design Professional) Equipment or Fixture 202 Existing (see Building) Existing Building 202 Existing Structure 202 Exit 504.1.4, 802.2.1, 802.4, 802.4.1, 804, 903.1, 903.3, 905.2, 905.3, 1011.5, 1011.5.1, Table 1011.5, 1011.8.2, 1102.2, 1305.2.3.2, 1305.2.6, 1305.2.10.1, 1305.2.11, 1305.2.11.1, 1305.2.12, 1305.2.13, 1305.2.15.1, Table 1305.2.15, Table 1306.1,

e Registered Design** Professional) Equipment or Fixture 202 Existing (see Building) Existing Building 202 Existing Structure 202 Exit 504.1.4, 802.2.1, 802.4, 802.4.1, 804, 903.1, 903.3, 905.2, 905.3, 1011.5, 1011.5.1, Table 1011.5, 1011.8.2, 1102.2, 1305.2.3.2, 1305.2.6, 1305.2.10.1, 1305.2.11, 1305.2.11.1, 1305.2.12, 1305.2.13, 1305.2.15.1, Table 1305.2.15, Table 1306.1,

A402 Exit, Horizontal 503.15, 804.10, 1305.2.3.1 Exterior Wall Covering 202 Addition and replacement 309 Automatic sprinkler systems 309.2.1 Exterior Wall Envelope 202 Addition and replacement 309 Automatic sprinkler systems 309.2.1

Fire Alarm Systems 803.4, 904.2, 1011.2.2,

1305.2.9 Fire Escapes 504, 802.2.1, 804.4.1.2, 1305.2.11, 1305.2.11.1 Fire Protection 106.2.2, 202, 403, 703, 801.3, 803, 804.7.1, 804.7.2, 904, 1001.2, 1004, 1011.1, 1011.2, 1011.2.1, 1011.2.2, 1011.8.4, 1102.3, 1501.2.1, 1501.3, 1509 Fire Ratings 804.7.1, 804.7.2, 1011.6.1, 1011.6.1.1, 1011.6.3, 1011.7, 1011.7.1, 1011.7.2, 1011.7.3, 1011.8.2, 1011.8.3, 1011.8.4, 1302.1.2, 1305.2.3.2, 1305.2.3.3, 1305.2.4, 1305.2.4.1, 1305.2.5, 1305.2.5.1, 1305.2.6, 1305.2.16.1, Table 1306.1,

Resource A

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

INDEX

Fire Safety 101.6, 104.2.4, 107.2, 1101.2, 1305.1, 1305.1.1, 1305.1.3, 1305.2.1, 1305.2.2, 1305.2.3, 1305.2.4, 1305.2.5, 1305.2.6, 1305.2.7, 1305.2.8, 1305.2.9, 1305.2.14, 1305.2.16, 1305.2.17, 1305.2.18, 1305.2.19, 1305.2.20, Table 1306.1, Table 1306.2, Table 1307.1, A102.1 Fire Safety During Construction and Demolition (see Construction Safeguards) Fire-Resistance Rating 802.2.1, 802.6, 803.1.1, 803.2.2.1, 902.2, 1011.6.1.1, 1011.6.3, 1011.7, 1011.8.2, 1302.1.2, 1305.1.1, 1305.2.4, 1305.2.4.1, 1305.2.5, 1305.2.5.1, 1305.2.6, 1305.2.16, 1305.2.16.1, 1306.1, Resource A Flame Spread Resource A Flood Hazard Area 104.3.1, 104.2.4.1, 109.3.3, 109.3.10, 202, 301.3, 401.3, 405.2.6, 502.2, 503.2, 507.3, 701.3, 1103.3, 1303.1.3,

1402.6

Glass 402.1, 406, 804.7.1, 804.7.2, 1011.8.2, 1305.2.10.1, Resource A Gravity Loads (see Structural Loads/Forces) Guards 802.5, 802.5.1, 802.5.2, 804.12, 804.12.1, 804.12.2 Guidelines for Structural Retrofit

Seismic Appendix A Wind Appendix C

Handrails 503.1, 804.4, 1011.5.1, 1011.5.4 Hazard Categories 1011.5, Table 1011.5, 1011.6, Table 1011.6, Table 1011.7 Height (see Building, Height) High-Rise Building 1011.6.1, 1305.2.17, 1305.2.19 Historic Building (see Building, Historic)

Incidental Use Areas 1002.2 Inspection 104.7.2, 104.4, 104.7, 105.2, 106.1, 106.3.1, 106.6, 109, 1402.7, A105.3, A105.4, A107.1, A107.4, A113.7, A205.3.1, A205.4, A304.4.3, A304.5, A406.3.4, A407.3 Interior Finishes 702.1, 702.2, 1011.3 Interior Trim 702.3

Live Load (see Structural Loads/Forces) Load-Bearing Element 105.2.2, 202, Resource A

Maintenance 105.2, 1501.3, 1501.6.6 Means of Egress 101.2, 105.2.2, 106.2.3, 107.2, 115.1, 202, 404, 501.2, 504.1.1, 504.1.2, 704, 802.2.1, 802.2.3, 802.6, 804, 903.1, 905, 1005, 1011.5, 1011.5.1, 1011.5.2, Table 1011.5, 1101.2, 1305.1, 1305.1.2, 1305.1.3, 1305.2.1, 1305.2.10, 1305.2.11, 1305.2.12, 1305.2.14, 1305.2.15, 1305.2.17, 1305.2.18, 1305.2.19, 1305.2.2, 1305.2.20, 1305.2.21.1, 1305.2.21.2, 1305.2.21.3, 1305.2.3, 1305.2.4, 1305.2.5, 1305.2.6, 1305.2.7, 1305.2.8, 1305.2.9, Table 1306.1, Table 1306.2, Table 1307.1, 1505 Mechanical 105.1, 105.1.1, 105.2, 105.2.2, 108.3, 302.2, 308.1, 407, 503.4, 702.7, 801.3, 807, 1008, 1101.2, 1305.2.7.1, 1305.2.8, 1305.2.8.1, 1305.2.10, 1305.2.10.1, 1501.2.1,

A102.1

Modifications 104.2.4 Moved Buildings (see Building, Relocated)

Noncombustible Material 202, 504.3, 804.4.1.2.2, Resource A

Occupiable Roof 202, 502.1, 804.14.2, 804.5.1.1, Table 804.5.1.1(1), Table 804.5.1.1(2), 1011.5.1, 1011.5.2, 1101.7,

1302.1.3 Openings 106.2.4, 116.2, 202, 504.5, 505, 506.4, 702.4, 702.5, 702.6, 802.2, 804.4.1.2.1, 804.6.3, 804.7, 804.7.3, 804.7.3.1, 804.7.4, 903.1, 1011.5.1, 1011.5.6, 1011.7.1, 1011.7.2, 1011.7.3, 1011.8, 1011.8.2, 1011.8.3, 1011.8.4, 1102.2, 1305.2.6, Table 1301.6.6(1), 1305.2.6.1, 1305.2.10.1, Table 1306.1, 1501.6.4

Peer Review 104.2.3.7, 202 Permits 101.4.1, 104.3, 104.3.2, 104.7, 105, 106.1, 106.2.6, 106.3.1, 106.3.2, 106.3.3, 106.6, 107.1, 107.4, 108.1, 108.2, 108.3, 108.4, 108.5, 109.1, 109.2, 109.3.11, 109.5, 109.6, 110.1, 110.2, 110.3, 111.1, 113.2, 113.4, 503.6, 706.1, 706.3, 706.3.1, A105.3 Photovoltaic Panel System 202, 503.4,

805.3 Plumbing 105.1, 105.1.1, 105.2, 108.3, 109.3.4, 202, 302.2, 308.1, 408, 702.7, 1009, 1101.2, 1302.1.6, 1501.7, A102.1, A304.1.3, A304.3.2, A304.4.2 Primary Function 202

Ramps 802.2.1, 1305.2.6, B101.3, B101.4 Referenced Standards Chapter 16 Refuge Areas 503.15, 804.10 Registered Design Professional 104.3.3, 106.1, 106.3.4, 106.6, 202, 405.2.3.1, A106.2.3.4, A301.1, A301.2, A301.3, A304.2.2, A304.2.3, A304.4.1, A405.3 Registered Design Professional in Responsible Charge 106.3.4, 106.6 Rehabilitation 104.3.1, 202, 405.2.4 Relocatable Buildings (see Buildings, Relocatable) Relocated Buildings (see Buildings, Relocated) Repair Chapter 4, 101.2, 101.3, 101.4, 101.6, 104.3, 104.3.1, 104.3.2, 104.2.4.1, 105.1, 105.2, 105.2.1, 105.2.2, 105.2.3, 106.2.6, 113.1, 113.2, 115.3, 115.5, 116.1, 116.4, 116.5, 117.1, 202, 301.1, 301.2, 302.2, 302.2.1, 302.4, 308.1, 309.1, 1101.3, 1303.1, 1401.2, 1402.7, 1501.3, 1501.6.6, A105.2, A105.3, A106.1, A106.2.1, A106.2.3.9, A403.2, C101.1, C201.1 Reroofing 705 Risk Category 202, 304.3.1, Table 304.3.1, 304.3.2, Table 304.3.2, 506.5.2, 506.5.3, 506.5.4, 1006.2, 1006.3, 1006.4, A102.2, A401.2, A403.3, C201.2 Roof 308.1, 405.2.5, 503.3, 503.4, 503.7, 503.8, 504.3, 705, 906.4, 906.5, 1501.2.1, 1501.6.5, 1502.1 Diaphragms 503.12, 706.3.2, 906.4 Permit 706.1, 706.3, 706.3.1 Recover 202, 705.3, 705.3.1, 705.3.1 Repair 202

Replacement 202, 705.1, 705.2 Reroofing 202, 503.6, 705, 706.3.1 Roof Coating 705.3

Safeguards During Construction (see Construction Safeguards) Safety Parameters 1305.1.3, 1305.2, Table

1306.1

Seismic Forces (see Structural Loads/Forces) Seismic Loads (see Structural Loads/Forces) Seismic Retrofit Appendix A Shaft Enclosures 802.2.2, 1011.8, 1305.2.6 Smoke Alarms 307

Smoke Compartments 503.14, 503.15, 802.3, 902.3, 904.1.5, 1101.5, 1305.2, 1305.2.20, 1305.2.20.1, Table 1305.2.20, 1305.2.21, 1305.2.21.1, 1305.2.21.2, 1305.2.21.2.1, Table 1306.1 Smoke Control 1305.2.10, 1305.2.10.1, Table 1305.2.10, Table 1306.1 Smoke Detectors 803.4, 1011.8.4, 1305.2.8.1 Snow Load (see Structural Loads/Forces) Special Use and Occupancy 802, 902, 1002 Sprinkler System (see Automatic Sprinkler System) Stairway 503.1, 504.1.3, 504.2, 504.4, 504.5, 506.3, 802.2.1, 802.2.2, 802.2.3, 803.1.1, 804.4.1.1, 804.4.1.2.1, 804.4.1.2.3, 804.6.3, 804.6.3.1, 804.10.1, 804.12.1, 806.4.5, 903.1, 1011.5.1, 1011.5.2, 1011.5.4, 1011.8.2, 1011.8.3, 1011.8.4, 1102.2, 1305.2.3, 1305.2.6, 1305.2.10.1, 1504.1, 1505.1,

1506.1 Standpipe Systems 105.2.2, 1305.2.18, 1305.2.18.1, Table 1305.2.18, Table 1306.1, 1503.2, 1506 Storm Shelter 303

Structural 304.1, 405, 502.3, 502.4, 503.3, 503.4, 503.5, 503.6, 503.7, 503.8, 503.9, 503.10, 503.11, 503.12, 503.13, 506.5, 507.4, 706, 805, 906, 1006, 1103, 1304.1.1, 1402 Structural Loads/Forces Gravity loads A403.10.1, A403.10.2, A403.5, 202, 304.1, 405.2.4, 405.2.4.1, 502.3, 503.3, 706.2, 805.2, 1007.1,

1103.1 International Building Code -level 506.5.3, 506.5.4, 1006.3, 1103.2,

1402.4

Live loads 804.4.1.2.2, A106.2.3.6, A403.7, A104.1, A108.3, A108.6, 202, 304.1, 405.2.4, 502.3, 503.3, 504.3, 506.5.1, 507.4, 706.2, 805.2, 1006.1, 1103.1, 1504.1.1, 1504.1.5 Reduced 304.3.2, Table 304.3.2, 405.2.3.1, 405.2.3.3, 503.10, 503.11, 503.4, 503.5, 503.6, 503.7, 503.8, 503.9, 506.5.3, 706.3.1, 805.3, 906.2, 906.3, 906.4, 906.5, 906.6, 906.7,

1006.3

Repairs 405 Seismic loads Appendix a, 202, 304.3, 405.2.3, 405.2.4.1, 502.2, 502.4, 503.10, 503.11, 503.13, 503.4, 503.5, 503.6, 503.7, 503.8, 503.9, 506.5.3, 506.5.4, 706.3.1, 805.3, 906.2, 906.3, 906.4, 906.5, 906.6, 906.7, 1006.3, 1006.4, 1103.2, 1402.4

INDEX-2 2025 CALIFORNIA EXISTING BUILDING CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

INDEX

Snow loads 304.2, 405.2.1.1, 405.2.4, 405.2.5, 502.3, 503.3, 506.5.2, 706.2, 805.2, 1006.2, 1103.1, 1402.5 Wind loads Appendix c, 303.1, 303.2, 405.2.3, 405.2.4.1, 503.12, 506.5.2, 706.3.2, 1006.2, 1402.3, 1504.1.7 Substantial Damage 202, 507.3, 1103.3 Substantial Improvement 104.3.1, 104.2.4.1, 109.3.3, 202, 401.3, 502.2, 503.2, 507.3, 701.3, 1103.3, 1201.4, 1303.1.3 Substantial Structural Alteration 202, 503.11, 906.2 Substantial Structural Damage 202, 405.2.1, 405.2.2, 405.2.3, 405.2.4, 405.2.4.1, 405.2.5, 502.2, 507.4

405.2.3, 405.2.4.1, 503.12, 506.5.2, 706.3.2, 1006.2, 1402.3, 1504.1.7 Substantial Damage 202, 507.3, 1103.3 Substantial Improvement 104.3.1, 104.2.4.1, 109.3.3, 202, 401.3, 502.2, 503.2, 507.3, 701.3, 1103.3, 1201.4, 1303.1.3 Substantial Structural Alteration 202, 503.11, 906.2 Substantial Structural Damage 202, 405.2.1, 405.2.2, 405.2.3, 405.2.4, 405.2.4.1, 405.2.5, 502.2, 507.4

Technical Assistance 104.2.2 Technically Infeasible 202 Temporary Emergency Uses Appendix E Temporary Structure 107 Testing 104.2.3.5, 111.2, 305, 1305.2.10.1, 1507.1, A104.1, A105.3, A105.4, A106.2.1, A106.2.3, A107.2, A107.3, A107.4, A107.5, A108.2, A108.5, A113.1.3, A114.1, A205.3.2, A205.4, A206.2, A304.2.2, A403.9.2.1, A405.3,

A407.3

Unsafe 104.4, 105.2, 114.1, 114.4, 115, 116.1, 116.2, 116.3, 116.5, 117.1, 202, 302.3, 302.4, 1007.2, 1303.1.1 Utilities 111

Vertical Opening Protection 802.2, 903.1, 1011.8, 1305.2.6, Table 1306.1 Violations 101.6, 104.4, 105.2, 105.4, 105.6, 109.1, 110.1, 110.2, 110.4, 113, 114.4

Wind Load (see Structural Loads/Forces) Windows Emergency escape and rescue openings 505.3, 505.3.1, 505.4, 702.5, 702.5.1, 702.6 Glazing 402.1, 804.7, 804.7.2 Opening control devices 505.2, 505.3.1, 702.4, 702.5.1 Replacement 505.1 Work Area 202, 301.3.2, 503.5, 503.7, 503.8, 503.9, 503.10, 503.11, 503.16, 503.18, 506.6, 601.2, 603.1, 604.1, 801.3, 802.1, 802.2.1, 802.2.2, 802.2.3, 802.3, 802.4, 802.4.1, 802.5, 803.1, 804.1, 804.2, 804.10.1, 804.10.2, 804.6, 804.6.1, 804.6.1.1, 804.6.1.2, 804.6.2, 804.6.2.1, 804.6.3, 804.6.3.1, 804.6.4, 804.6.4.1, 804.7, 804.7.1, 804.7.2, 804.7.3, 804.7.3.1, 804.7.4, 804.8, 804.9, 804.9.1, 804.9.2, 804.10.1, 804.10.2, 804.4, 804.10.1, 804.12, 806.1, 806.2, 807.1, 901.2, 903.1, 903.2.1, 903.3, 903.4, 904.1, 904.2.1, 904.2.2, 905.2, 905.3, 906.7

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

INDEX-4 2025 CALIFORNIA EXISTING BUILDING CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

HISTORY NOTE APPENDIX

California Code of Regulations, Title 24, Part 10

HISTORY:

For prior code history, see the History Note Appendix to the California Existing Building Code, 2022 Triennial Edition, effective January 1, 2023.

1. (BSC 06/24, DSA-AC 01/24, DSA-SS 06/24, HCD 06/24, OSHPD 06/24, SFM 09/24)—Adoption by reference of the 2024 Interna- tional Existing Building Code with necessary amendments to become the 2025 California Existing Building Code, and repeal of the 2021 edition of the International Existing Building Code . Approved by the California Building Standards Commission on February 26, 2025, filed with Secretary of State on March 7, 2025, and effective on January 1, 2026.

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

HIST-2 2025 CALIFORNIA EXISTING BUILDING CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.