CHBC · California Historical Building Code
How are required occupancy separations treated for historic buildings?
If your qualified historic building is fully protected by an automatic sprinkler system, the CHBC lets you reduce separations greater than one hour down to one hour (with openings protected by 3/4‑hour self‑closing or automatic‑closing assemblies) — and it even allows omitting one‑hour separations entirely. Confirm sprinkler standards and assembly ratings with the CHBC chapters referenced in **§ 8‑302.3**, **§ 8‑302.6**, and **§ 8‑405**, and coordinate with the enforcing agency.
Last reviewed: July 6, 2026
What the code requires — 2–4 sentences
Under the CHBC, required occupancy separations in qualified historical buildings may be eased when certain fire-protection measures are provided. Specifically, § 8-302.3 allows required separations of more than one hour to be reduced to one-hour fire-resistive construction with openings protected by three‑fourths‑hour assemblies when the building has an automatic sprinkler system throughout; and one‑hour required separations may be omitted entirely when an automatic sprinkler system is provided throughout the building. See § 8-302.3 for the rule and related cross-references to fire‑resistive construction in § 8-302.6 and occupancy‑separation location in § 8-405.
The single most important rule: If you provide an automatic sprinkler system throughout a qualified historical building, the CHBC lets you reduce or even omit certain required occupancy separations that would otherwise be stricter.
Requirements in detail
Short plain-English synopsis of the mechanics
- When the historical building is fully sprinklered, separations required by the regular code that exceed one hour can be reduced to one‑hour fire‑resistive construction, but all openings in that separation must be protected by not less than three‑fourths‑hour fire‑resistive assemblies that are self‑closing or automatic‑closing and must actuate on products of combustion (not heat alone). § 8-302.3.
- If the required separation is one hour, that separation may be omitted when the building is provided with an automatic sprinkler system throughout. § 8-302.3.
Decision‑relevant values (quick reference table)
| Decision factor | Value / Action allowed under CHBC | What you must provide or do | Code Reference |
|---|---|---|---|
| Required separation originally > 1 hour | Reduce to 1‑hour fire‑resistive construction | All openings protected by ≥ 3/4‑hour fire‑resistive assemblies that are self‑closing or automatic‑closing and operate on products of combustion; building must have automatic sprinkler system throughout | § 8-302.3 |
| Required separation originally = 1 hour | Omit the required separation | Building must have automatic sprinkler system throughout | § 8-302.3 |
| What counts as fire‑resistive construction | See CHBC Chapter 8‑4 (fire protection provisions govern details and tests) | Use Chapter 8‑4 provisions when designing or rating assemblies | § 8-302.6 |
| Where to find occupancy‑separation rules in CHBC | Primary occupancy separation rules and reductions are in Chapter 8‑3 (use & occupancy) | Cross‑reference: Chapter 8‑4 for construction details; Chapter 8‑3 contains the operative reductions | § 8-405 (“See Chapter 8‑3”) |
| Sprinkler standard references | CHBC defines required sprinkler standards (NFPA 13/13R/13D) when automatic sprinklers are required | Follow the applicable NFPA standard referenced in CHBC § 8‑410.2 for system design | § 8-410.2 |
How doors/openings must be treated
- Doors in the occupancy separation that rely on automatic‑closing devices must be of a type that will function upon activation of a device that responds to products of combustion other than heat (i.e., smoke detection activation), not just heat‑sensing devices. § 8-302.3.
Exceptions & special cases
- The CHBC explicitly ties these reductions/omissions to the presence of an automatic sprinkler system throughout the entire building; localized sprinkling does not satisfy the stated condition unless the system meets the CHBC’s definitions/standards for the situation (see § 8-410.2 for NFPA standards referenced by CHBC).
- The CHBC cross‑references fire‑resistive construction details to Chapter 8‑4 (see § 8-302.6), so actual assembly ratings and permitted historic materials (e.g., wood lath & plaster provisions in § 8-404) must be checked for applicability and acceptance by the enforcing agency. § 8-302.6, § 8-404.
- Occupancy separation provisions are implemented as part of the CHBC’s approach to preserve historic fabric — the enforcing agency may accept “reasonably equivalent” alternatives where appropriate. The CHBC is performance‑oriented; consult the enforcing agency and the State Historical Building Safety Board for interpretations where needed. (See CHBC administration and intent throughout Part 8.)
Common mistakes
- Assuming that any sprinkler (partial system) suffices. The CHBC requires an automatic sprinkler system throughout the entire building for the reduction/omission to apply — partial or isolated sprinkling is not the trigger stated in § 8-302.3.
- Confusing area separations or fire‑area walls with occupancy separations — the CHBC reduction language specifically addresses required occupancy separations; other area/height/area limits have their own CHBC provisions (see §§ 8‑302.4 and 8‑406).
- Overlooking the door‑device requirement — automatic‑closing doors must actuate on products of combustion, not just heat. Don’t install heat‑only detectors if the automatic‑closing device is intended to satisfy § 8‑302.3.
- Failing to check Chapter 8‑4 for how historic materials are rated (for example, wood lath & plaster may have recognized hour‑ratings under historical listings). Always confirm assembly ratings with Chapter 8‑4 provisions.
Worked example — concrete scenario
Scenario: A qualified historic building contains two adjacent occupancies that the regular code requires to be separated by a 2‑hour fire‑resistive occupancy separation (with standard rated openings). The owner wants to preserve original openings and avoid constructing a new 2‑hour wall.
Application of CHBC:
- Because the existing required separation is more than one hour (2 hours), the owner may reduce the separation to one‑hour fire‑resistive construction provided the entire building is fitted with an automatic sprinkler system throughout, and all openings in that separation are protected by not less than three‑fourths‑hour fire‑resistive assemblies that are self‑closing or automatic‑closing (actuated by products of combustion). This is permitted by § 8‑302.3.
- If the original required separation had been one hour, the owner could instead omit the separation entirely when the building is sprinklered throughout (also per § 8‑302.3).
- Design note: Select the sprinkler standard per CHBC (e.g., NFPA 13R or NFPA 13) in accordance with § 8‑410.2, and ensure door closers respond to smoke products (not heat only). Confirm any historic assembly ratings under Chapter 8‑4 if relying on original plaster/lath.
Related provisions
- § 8-302.3 — Occupancy separations (primary controlling text on reduction/omission).
- § 8-302.6 — Fire‑resistive construction (see Chapter 8‑4 for assembly/rating details).
- § 8-405 — Occupancy separation (cross‑references to Chapter 8‑3 where reductions are located).
- § 8-410.2 — Automatic sprinkler system standards and which NFPA standard to apply (relevant because § 8‑302.3 conditions are tied to sprinklers throughout).
- § 8-404 — Wood lath and plaster fire‑rating guidance (useful if relying on historic assemblies to meet 1‑hour or 3/4‑hour ratings).
- Chapter 8‑3 (Use & Occupancy) and Chapter 8‑4 (Fire Protection) generally — the CHBC places occupancy separation policy in Chapter 8‑3 and technical construction/rating details in Chapter 8‑4; check both when designing solutions.
Code references
Grounded in the retrieved California Historical Building Code — click a citation to read the verbatim passage:
CHBC § 8-3 High relevance — show source text
TREATMENT. An act of work to carry out preservation, restoration, stabilization, rehabilitation or reconstruction.
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8-3 USE AND OCCUPANCY
SECTION 8-301 — PURPOSE AND SCOPE
8-301.1 Purpose. The purpose of the CHBC is to provide regulations for the determination of occupancy classifications and conditions of use for qualified historical buildings or properties.
8-301.2 Scope. Every qualified historical building or property for which a permit or approval has been requested shall be classified prior to permit issuance according to its use or the character of its occupancy in accordance with the regular code and applicable provisions of this chapter.
SECTION 8-302 — GENERAL
8-302.1 Existing use. The use or character of occupancy of a qualified historical building or property, or portion thereof, shall be permitted to continue in use regardless of any period of time in which it may have remained unoccupied or in other uses, provided such building or property otherwise conforms to all applicable requirements of the CHBC.
8-302.2 Change in occupancy. The use or character of the occupancy of a qualified historical building or property may be changed from or returned to its historical use or character, provided the qualified historical building or property conforms to the requirements applicable to the new use or character of occupancy as set forth in the CHBC. Such change in occupancy shall not mandate conformance with new construction requirements as set forth in regular code.
8-302.3 Occupancy separations. Required occupancy separations of more than one hour may be reduced to one-hour fire-resistive construction with all openings protected by not less than three-fourths-hour fire-resistive assemblies of the self-closing or automatic-closing type when the building is provided with an automatic sprinkler system throughout the entire building in accordance with Section 8-410.2. Doors equipped with automatic-closing devices shall be of a type which will function upon activation of a device which responds to products of combustion other than heat.
Required occupancy separations of one hour may be omitted when the building is provided with an automatic sprinkler system throughout.
8-302.4 Maximum floor area. Regardless of the use or character of occupancy, the area of a one-story qualified historical building or property may have, but shall not exceed, a floor area of 15,000 square feet (1393.5 m [2] ) unless such an increase is otherwise permitted in regular code. Multistory qualified historical buildings (including basements and cellars) shall be in accordance with regular code requirements.
Exception: Historical buildings may be unlimited in floor area without fire-resistive area separation walls:
- When provided with an automatic sprinkler, or
- Residential occupancies of two stories or less when provided with a complete fire alarm and annunciation system and where the exiting system conforms to regular code.
8-302.5 Maximum height. The maximum height and number of stories of a qualified historical building or property shall not be limited because of construction type, provided such height or number of stories does not exceed that of its historical design.
CHBC § 8-302.3 High relevance — show source text
8-302.3 Occupancy separations. Required occupancy separations of more than one hour may be reduced to one-hour fire-resistive construction with all openings protected by not less than three-fourths-hour fire-resistive assemblies of the self-closing or automatic-closing type when the building is provided with an automatic sprinkler system throughout the entire building in accordance with Section 8-410.2. Doors equipped with automatic-closing devices shall be of a type which will function upon activation of a device which responds to products of combustion other than heat.
Required occupancy separations of one hour may be omitted when the building is provided with an automatic sprinkler system throughout.
8-302.4 Maximum floor area. Regardless of the use or character of occupancy, the area of a one-story qualified historical building or property may have, but shall not exceed, a floor area of 15,000 square feet (1393.5 m [2] ) unless such an increase is otherwise permitted in regular code. Multistory qualified historical buildings (including basements and cellars) shall be in accordance with regular code requirements.
Exception: Historical buildings may be unlimited in floor area without fire-resistive area separation walls:
- When provided with an automatic sprinkler, or
- Residential occupancies of two stories or less when provided with a complete fire alarm and annunciation system and where the exiting system conforms to regular code.
8-302.5 Maximum height. The maximum height and number of stories of a qualified historical building or property shall not be limited because of construction type, provided such height or number of stories does not exceed that of its historical design.
8-302.5.1 High-rise buildings. Occupancies B, F-1, F-2 or S in high-rise buildings with floors located more than 75 feet above the lowest floor level having building access may be permitted with only the stories over 75 feet provided with an automatic fire sprinkler system if:
- The building construction type and the exits conform to regular code, and
- A complete building fire alarm and annunciation system is installed, and
- A fire barrier is provided between the sprinklered and nonsprinklered floors.
8-302.6 Fire-resistive construction. See Chapter 8-4.
8-302.7 Light and ventilation. Existing provisions for light and ventilation which do not, in the opinion of the enforcing agency, constitute a safety hazard may remain. See Section 8-303.6 for residential requirements. See Section 8-503 for Escape or Rescue Windows and Doors.
SECTION 8-303 — RESIDENTIAL OCCUPANCIES
8-303.1 Purpose. The purpose of this section is to provide regulations for those buildings designated as qualified historical buildings or properties and classified as residential occupancies. The CHBC requires enforcing agencies to accept any reasonably equivalent alternative to the regular code when dealing with qualified historical buildings and properties.
8-303.2 Intent. The intent of the CHBC is to preserve the integrity of qualified historical buildings and properties while maintaining a reasonable degree of protection of life, health and safety for the occupants.
8-303.3 Application and scope. The provisions of this section shall apply to all qualified historical buildings used for human habitation. Those dwelling units intended only for display, or public use with no residential use involved, need not comply with the requirements of this section.
8-303.4 Fire escapes. See Chapter 8-5.
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CHBC § 8-301 Medium relevance — show source text
Section
8-301 Purpose and Scope. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 8-302 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
8-303 Residential Occupancies. . . . . . . . . . . . . . . . . . . . . . . . . 5
CHAPTER 8-4 FIRE PROTECTION. . . . . . . . . . . . . . . . . . . . . . . 7
Section
8-401 Purpose, Intent and Scope . . . . . . . . . . . . . . . . . . . . . . . 7
8-402 Fire-resistive Construction . . . . . . . . . . . . . . . . . . . . . . . 7
8-403 Interior Finish Materials. . . . . . . . . . . . . . . . . . . . . . . . . . 7
8-404 Wood Lath and Plaster. . . . . . . . . . . . . . . . . . . . . . . . . . . 7
8-405 Occupancy Separation . . . . . . . . . . . . . . . . . . . . . . . . . . 7 8-406 Maximum Floor Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
8-407 Vertical Shafts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
8-408 Roof Covering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 8-409 Fire Alarm Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 8-410 Automatic Sprinkler Systems. . . . . . . . . . . . . . . . . . . . . 8 8-411 Other Technologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 8-412 High-rise Buildings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
CHAPTER 8-5 MEANS OF EGRESS . . . . . . . . . . . . . . . . . . . . . . 9
Section
8-501 Purpose, Intent and Scope . . . . . . . . . . . . . . . . . . . . . . . 9 8-502 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
8-503 Escape or Rescue Windows and Doors. . . . . . . . . . . . 10 8-504 Railings and Guardrails . . . . . . . . . . . . . . . . . . . . . . . . . 10
CHBC § 8-3 Medium relevance — show source text
This shall include historical buildings or properties on, or determined eligible for, national, state or local historical registers or inventories, such as the National Register of Historic Places, California Register of Historical Resources, State Historical Landmarks, State Points of Historical Interest, and city or county registers, inventories or surveys of historical or architecturally significant sites, places or landmarks.
RECONSTRUCTION. The act or process of depicting, by means of new construction, the form, features and detailing of a nonsurviving site, landscape, building, property or object for the purpose of replicating its appearance at a specific period of time.
REGULAR CODE. The adopted regulations that govern the design and construction or alteration of nonhistorical buildings and properties within the jurisdiction of the enforcing agency.
REHABILITATION. The act or process of making possible a compatible use for qualified historical building or property through repair, alterations and additions while preserving those portions or features which convey its qualified historical, cultural or architectural values.
RELOCATION. The act or process of moving any qualified historical building or property or a portion of a qualified historical building or property to a new site, or a different location on the same site.
REPAIR. Renewal, reconstruction or renovation of any portion of an existing property, site or building for the purpose of its continued use.
RESTORATION. The act or process of accurately depicting the form, features and character of a qualified building or property as it appeared at a particular period of time by the means of the removal of features from other periods in its history and reconstruction of missing features from the restoration period. The limited and sensitive upgrading of mechanical, electrical and plumbing systems and other code-required work to make properties functional is appropriate within a restoration project.
STRUCTURE. That which is built or constructed, an edifice or a building of any kind, or any piece of work artificially built up or composed of parts joined together in some definite manner.
TREATMENT. An act of work to carry out preservation, restoration, stabilization, rehabilitation or reconstruction.
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8-3 USE AND OCCUPANCY
SECTION 8-301 — PURPOSE AND SCOPE
8-301.1 Purpose. The purpose of the CHBC is to provide regulations for the determination of occupancy classifications and conditions of use for qualified historical buildings or properties.
8-301.2 Scope. Every qualified historical building or property for which a permit or approval has been requested shall be classified prior to permit issuance according to its use or the character of its occupancy in accordance with the regular code and applicable provisions of this chapter.
SECTION 8-302 — GENERAL
8-302.1 Existing use. The use or character of occupancy of a qualified historical building or property, or portion thereof, shall be permitted to continue in use regardless of any period of time in which it may have remained unoccupied or in other uses, provided such building or property otherwise conforms to all applicable requirements of the CHBC.
8-302.2 Change in occupancy. The use or character of the occupancy of a qualified historical building or property may be changed from or returned to its historical use or character, provided the qualified historical building or property conforms to the requirements applicable to the new use or character of occupancy as set forth in the CHBC. Such change in occupancy shall not mandate conformance with new construction requirements as set forth in regular code.
CHBC § 2.1 Medium relevance — show source text
Exceptions:
- Any stairway replacing an existing stairway within a space where the pitch or slope cannot be reduced shall not be required to comply with the maximum riser height and minimum tread depth requirements.
- In Group R-2.1 and I-2 facilities, required guards enclosing the occupiable roof areas shall be permitted to be greater than 48 inches (1219 mm) above the surface of the occupiable roof where the occupants, because of clinical needs, require restraint or containment as part of a function of a psychiatric or cognitive treatment area.
1011.5.3 Egress capacity. Egress capacity shall meet or exceed the occupant load as specified in the California Building Code for the new occupancy.
1011.5.4 Handrails. Existing stairways shall comply with the handrail requirements of Section 804.13.
1011.5.5 Guards. Existing guards shall comply with the requirements in Section 804.12.
1011.5.6 Existing emergency escape and rescue openings. Where a change of occupancy would require an emergency escape and rescue opening in accordance with Section 1031 of the California Building Code, operable windows serving as the emergency escape and rescue opening shall comply with the following:
- An existing operable window shall provide a minimum net clear opening of 4 square feet (0.38 m [2] ) with a minimum net clear opening height of 22 inches (559 mm) and a minimum net clear opening width of 20 inches (508 mm).
- A replacement window where such window complies with both of the following: 2.1. The replacement window meets the size requirements in Item 1. 2.2. The replacement window is the manufacturer’s largest standard size window that will fit within the existing frame or existing rough opening. The replacement window shall be permitted to be of the same operating style as the existing window or a style that provides for an equal or greater window opening area than the existing window.
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CHANGE OF OCCUPANCY
1011.6 Heights and areas. Hazard categories in regard to height and area shall be in accordance with Table 1011.6.
TABLE 1011.6—HEIGHTS AND AREAS HAZARD CATEGORIES Col2 RELATIVE HAZARD OCCUPANCY CLASSIFICATIONS 1 (Highest Hazard) H 2 A-1; A-2; A-3; A-4; I; R-1; R-2; R-4, Condition 2 3 E; F-1; S-1; M 4 (Lowest Hazard) B; F-2; S-2; A-5; R-3; R-4, Condition 1; U 1011.6.1 Height and area for change to a higher-hazard category. Where a change of occupancy classification is made to a higher-hazard category as shown in Table 1011.6, heights and areas of buildings and structures shall comply with the requirements of Chapter 5 of the California Building Code for the new occupancy classification.
Exceptions:
- For high-rise buildings constructed in compliance with a previously issued permit, the type of construction reduction specified in Section 403.2.1 of the California Building Code is permitted. This shall include the reduction for columns.
CHBC § 1.10.1 Medium relevance — show source text
Chapter 5A Prescriptive Compliance Method.
Chapter 5A provides details for the prescriptive compliance method for alteration, addition and change of occupancy of existing build- ings and structures regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development, which include hospitals and correctional treatment centers (applications listed in Sections 1.10.1 (OSHPD 1).
Chapter 6 Classification of Work.
Chapter 6 provides an overview of the Work Area Method and defines the different classifications of work including alterations, change of occupancy, additions and historic buildings. Detailed requirements for all of these are given in subsequent Chapters 7 through 11.
Chapter 7 Alterations—Level 1.
Chapter 7 provides the technical requirements for those existing buildings that undergo Level 1 alterations as described in Section 602, which includes replacement or covering of existing materials, elements, equipment or fixtures using new materials for the same purpose. This chapter is distinguished from Chapters 8 and 9 by only involving replacement of building components with new components with no reconfiguration of space.
Chapter 8 Alterations—Level 2.
A Level 2 alteration is an alteration involving space reconfiguration that could be up to and including 50 percent of the area of the building or addition of a new building system. Level 2 alterations also include the extension or addition of any system or equipment. The purpose of Chapter 8 is to provide detailed requirements and provisions to identify the required improvements in the existing building elements, means of egress, fire protection, structural systems, energy efficiency, and other building systems include electrical, mechanical and plumbing when a building is being altered.
Chapter 9 Alterations—Level 3.
Chapter 9 provides the technical requirements for those existing buildings that undergo Level 3 alterations. Level 3 alterations are those involving alterations that cover 50 percent of the aggregate area of the building. Under certain situations, this chapter also intends to improve the safety of certain building features beyond the work area and in other parts of the building where no alteration work might be taking place.
Chapter 10 Change of Occupancy.
The purpose of Chapter 10 is to address existing buildings that are subject to a change of occupancy. This chapter is an assembly of requirements to upgrade safety without having to comply fully as a new building. A change of occupancy classification is considered a change of occupancy, however, it will involve a higher level of regulation since the use of the building has made a more significant change.
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Chapter 11 Additions.
Chapter 11 provides the requirements for additions, which are considered new construction. The requirements focus on safely integrating the addition with the existing building. This includes issues such as limiting the overall height and area of the building where the addition is not separated by a fire wall.
Chapter 12 Historic Buildings —Reserved
Chapter 12 is not adopted by the State of California. Historic buildings and structures shall comply with Part 8, Title 24, California Code of Regulations.
Chapter 13 Performance Compliance Methods.
Chapter 13 allows for existing buildings to be evaluated to show that alterations or a change of occupancy, while not meeting new construction requirements, will provide a level of safety to demonstrate compliance. Provisions are based on a numerical scoring system involving 21 safety parameters where, when evaluated, such buildings must meet a minimum overall safety score.
CHBC § 8-1002.1 Medium relevance — show source text
8-1002.1 The CHBC shall apply to all sites and districts and their features associated with qualified historical buildings or qualified historical districts as outlined in 8-1001.2 Scope.
8-1002.2 Where the application of regular code may impact the associated features of qualified historical properties beyond their footprints, by work performed secondarily, those impacts shall also be covered by the CHBC.
8-1002.3 This chapter shall be applied for all issues regarding code compliance or other standard or regulation as they affect the purpose of this chapter.
8-1002.4 The application of any code or building standard shall not unduly restrict the use of a qualified historical building or property that is otherwise permitted pursuant to Chapter 8-3 and the intent of the State Historical Building Code, Section 18956.
SECTION 8-1003 — SITE RELATIONS
The relationship between a building or property and its site, or the associated features of a district (including qualified historical landscape), site, objects and their features are critical components that may be one of the criteria for these buildings and properties to be qualified under the CHBC. The CHBC recognizes the importance of these relationships. This chapter shall be used to provide context sensitive solutions for treatment of qualified historical buildings, properties, district or their associated historical features, or when work to be performed secondarily impacts the associated historical features of a qualified historical building or property.
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APPENDIX A Col2 Col3 Col4 CHAPTER 8-6—TABLE 1—PROVISION APPLICABILITY CHAPTER 8-6—TABLE 1—PROVISION APPLICABILITY CHAPTER 8-6—TABLE 1—PROVISION APPLICABILITY CHAPTER 8-6—TABLE 1—PROVISION APPLICABILITY Title II
Public EntitiesTitle III
Private EntitiesTitle III
Barrier RemovalSECTION 8-601 PURPOSE, INTENT, SCOPE
**8-601.1 Purpose.**The purpose of the CHBC is to provide alternative regulations to facilitate
access and use by persons with disabilities to and throughout facilities designated as quali-
fied historical buildings or properties. These regulations require enforcing agencies to
accept alternatives to regular code when dealing with qualified historical buildings or
properties.
**8-601.2 Intent.**The intent of this chapter is to preserve the integrity of qualified historical
buildings and properties while providing access to and use by persons with disabilities.
**8-601.3 Scope.**The CHBC shall apply to every qualified historical building or property that
is required to provide access to persons with disabilities.
1.Provisions of this chapter do not apply to new construction or reconstruction/replicas of
historical buildings.
2. Where provisions of this chapter apply to alteration of qualified historical buildings or
properties, alteration is defined in_ California Building Code_ (CBC), Chapter 2.
**8-601.4 General application.CHBC § 8-102.1.1 Medium relevance — show source text
- State agencies. All state agencies shall apply the provisions of the CHBC in permitting repairs, alterations and additions necessary for the preservation, restoration, rehabilitation, safety, relocation, reconstruction or continued use of qualified historical buildings or properties.
8-102.1.1 Additions, alterations and repairs. It is the intent of the CHBC to allow nonhistorical expansion or addition to a qualified historical building or property, provided nonhistorical additions shall conform to the requirements of the regular code (as defined in Chapter 8-2).
8-102.1.2 Relocation. Relocated qualified historical buildings or properties shall be sited to comply with the regular code or with the solutions listed in the CHBC. Nonhistorical new construction related to relocation shall comply with the regular code. Reconstruction and restoration related to relocation is permitted to comply with the provisions in the CHBC.
8-102.1.3 Change of occupancy. For change of use or occupancy, see Chapter 8-3, Use and Occupancy.
8-102.1.4 Continued use. Qualified historical buildings or properties may have their existing use or occupancy continued if such use or occupancy conformed to the code or to the standards of construction in effect at the time of construction, and such use or occupancy does not constitute a distinct hazard to life safety as defined in the CHBC.
8-102.1.5 Unsafe buildings or properties. When a qualified historical building or property is determined to be unsafe as defined in the regular code, the requirements of the CHBC are applicable to the work necessary to correct the unsafe conditions. Work to remediate the buildings or properties need only address the correction of the unsafe conditions, and it shall not be required to bring the entire qualified historical building or property into compliance with regular code.
8-102.1.6 Additional work. Qualified historical buildings or properties shall not be subject to additional work required by the regular code, regulation or ordinance beyond that required to complete the work undertaken. Certain exceptions for accessibility and for distinct hazards exist by mandate and may require specific action, within the parameters of the CHBC.
SECTION 8-103 — ORGANIZATION AND ENFORCEMENT
8-103.1 Authority. The state or local enforcing agency, pursuant to authority provided under Section 18954 of the Health and Safety Code, shall administer and enforce the provisions of the CHBC in permitting repairs, alterations and additions necessary for the preservation, restoration, reconstruction, rehabilitation, relocation or continued use of a qualified historical building or property.
8-103.2 State enforcement. All state agencies pursuant to authority provided under Section 18954 and Section 18961 of the Health and Safety Code shall administer and enforce the CHBC with respect to qualified historical buildings or properties under their respective jurisdiction.
8-103.3 Liability. Prevailing law regarding immunity of building officials is unaffected by the use and enforcement of the CHBC.
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ADMINISTRATION
SECTION 8-104 — REVIEW AND APPEALS
8-104.1 State Historical Building Safety Board (SHBSB or Board). In order to provide for interpretation of the provisions of the CHBC and to hear appeals, the SHBSB shall act as an appeal and review body to state and local agencies or any affected party.
**8-104.2 SHBSB review.
CHBC § 8-404 Medium relevance — show source text
Exception: When an automatic sprinkler system is provided throughout the building, existing finishes shall be approved.
SECTION 8-404 — WOOD LATH AND PLASTER
Wood lath and plaster walls may be considered in accordance with codes, standards and listings published prior to 1943 whereby a wood stud wall assembly with gypsum or lime plaster on hand split or sawn wooden lath obtains a one-half-hour fire-resistive rating. This rating may be increased for interior walls to as much as one hour by filling the wall with mineral fiber or glass fiber.
SECTION 8-405 — OCCUPANCY SEPARATION
See Chapter 8-3.
SECTION 8-406 — MAXIMUM FLOOR AREA
See Chapter 8-3.
SECTION 8-407 — VERTICAL SHAFTS
Vertical shafts need not be enclosed when such shafts are blocked at every floor level by the installation of not less than 2 full inches (51 mm) of solid wood or equivalent construction to prevent the initial passage of smoke and flame. Automatic sprinkler systems or other solutions may be considered on a case-by-case basis, in lieu of enclosure of vertical shafts and stairwells.
SECTION 8-408 — ROOF COVERING
Existing or original roofing materials may be repaired or reconstructed subject to the following requirements:
- The original or historical roofing system shall be detailed or modified as necessary in order to be capable of providing shelter while preserving the historical materials and appearance of the roof.
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FIRE PROTECTION
- Wooden roof materials may be utilized where fire resistance is required, provided they are treated with fire-retardant treatments to achieve a Class “B” roof covering rating. Wood roofing in state designated Urban Wildland and High Fire Zones shall be permitted when installed in Class “A” assemblies.
- Jurisdictions that prohibit wood roofing materials for application as roof coverings and roof assemblies shall submit documentation for the adoption. Express Terms, statement of reasons and minutes of the action by the adopting authority Health and Safety Code, Section 18959(f).
SECTION 8-409 — FIRE ALARM SYSTEMS
Every qualified historical building or property shall be provided with fire alarm systems as required for the use or occupancy by the regular code or other approved alternative.
SECTION 8-410 — AUTOMATIC SPRINKLER SYSTEMS
8-410.1 Every qualified historical building or property which cannot be made to conform to the construction requirements specified in the regular code for the occupancy or use, and which constitutes a distinct fire hazard (for definition of “Distinct Hazard,” see Chapter 8-2), shall be deemed to be in compliance if provided with an automatic sprinkler system or a life safety system or other technologies as approved by the enforcing agency. (“Automatic” is defined in the regular code. “Sprinkler System” is defined in this section.)
8-410.2 When required by the CHBC, an automatic sprinkler system is defined by the following standards as adopted by the State Fire Marshal (for nonhazardous occupancies).
- Buildings of four stories or less: NFPA 13R.
- For floors above the fourth, NFPA 13.
CHBC § 323-9843 Medium relevance — show source text
State Librarian [SL]
library.ca.gov csllaw@library.ca.gov (916) 323-9843 Public Library Construction & Renovation
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HOW TO DETERMINE WHERE CHANGES HAVE BEEN MADE
Symbols in the margins indicate where changes have been made or language has been deleted.
This symbol indicates that a change has been made.
- This symbol indicates deletion of language.
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PART 8 CONTAINS ALTERNATIVE REGULATIONS
FOR QUALIFIED HISTORICAL BUILDINGS
The California Historical Building Code (CHBC) is unique among state regulations. The authoring of the original CHBC required state agencies promulgating regulations for building construction to work in harmony with representatives of other design and construction disciplines. The result was a totally new approach to building codes for historical structures, which maintains currently acceptable life safety standards. These regulations are also unique in that they are performance oriented rather than prescriptive. The provisions of the CHBC are to be applied by the enforcing authority of every city, county, city and county, or state agency in permitting repairs, alterations and additions necessary for the preservation, rehabilitation, relocation, related construction, change of use or continued use of a qualified historical building. The authority for use of the CHBC is vested in Sections 18950 through 18961 of the Health and Safety Code. Section 18954 states, “The building department of every city or county or other local agency that has jurisdiction over the enforcement of code within its legal authority shall apply the alternative standards and regulations adopted pursuant to Section 18959.5 in permitting repairs, alterations, and additions necessary for the preservation, restoration, rehabilitation, safety, moving, or continued use of a qualified historical building or structure. A state agency shall apply the alternative regulations adopted pursuant to Section 18959.5 in permitting repairs, alterations, and additions necessary for the preservation, restoration, rehabilitation, safety, moving, or continued use of a qualified historical building or structure.” However, be aware that in order to use the CHBC, the structure under consideration must be qualified by being designated as an historical building or structure. Section 18955 states, “For the purposes of this part, a qualified historical building or structure is any structure or property, collection of structures, and their related sites deemed of importance to the history, architecture, or culture of an area by an appropriate local or state governmental jurisdiction. This shall include historical buildings or structures on existing or future national, state or local historical registers or official inventories, such as the National Register of Historic Places, State Historical Landmarks, State Points of Historical Interest, and city or county registers or inventories of historical or architecturally significant sites, places, historic districts, or landmarks. This shall also include places, locations, or sites identified on these historical registers or official inventories and deemed of importance to the history, architecture, or culture of an area by an appropriate local or state governmental jurisdiction.” The regulations of the CHBC have the same authority as state law and are to be considered as such. Liability is the same as for prevailing law. The intent of the CHBC is to save California’s architectural heritage by recognizing the unique construction problems inherent in historical buildings and by providing a code to deal with these problems.
CHBC § 8-1001 Medium relevance — show source text
Section
8-1001 Purpose and Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 8-1002 Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 8-1003 Site Relations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
APPENDIX A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
HISTORY NOTE APPENDIX . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
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8-1 ADMINISTRATION
Note: The California Historical Building Code, Part 8 of Title 24, governs for all qualified historical buildings or properties in the State of California.
SECTION 8-101 — TITLE, PURPOSE AND INTENT
8-101.1 Title. These regulations shall be known as the California Historical Building Code and will be referred to herein as “the CHBC.”
8-101.2 Purpose. The purpose of the CHBC is to provide regulations for the preservation, restoration, rehabilitation, relocation or reconstruction of buildings or properties designated as qualified historical buildings or properties (as defined in Chapter 8-2). The CHBC is intended to provide solutions for the preservation of qualified historical buildings or properties, to promote sustainability, to provide access for persons with disabilities, to provide a cost-effective approach to preservation, and to provide for the reasonable safety of the occupants or users. The CHBC requires enforcing agencies to accept solutions that are reasonably equivalent to the regular code (as defined in Chapter 8-2) when dealing with qualified historical buildings or properties.
8-101.3 Intent. The intent of the CHBC is to facilitate the preservation and continuing use of qualified historical buildings or properties while providing reasonable safety for the building occupants and access for persons with disabilities.
SECTION 8-102 — APPLICATION
8-102.1 Application. The CHBC is applicable to all issues regarding code compliance for qualified historical buildings or properties. The CHBC may be used in conjunction with the regular code to provide solutions to facilitate the preservation of qualified historical buildings or properties. The CHBC shall be used by any agency with jurisdiction and whenever compliance with the code is required for qualified historical buildings or properties.
- State or local enforcing agency. The state or local enforcing agency shall apply the provisions of the CHBC in permitting repairs, alterations and additions necessary for the preservation, restoration, reconstruction, rehabilitation, relocation or continued use of a qualified historical building or property when so elected by the private property owner.
- **State agencies.
CHBC § 8-101.1 Medium relevance — show source text
8-101.1 Title. These regulations shall be known as the California Historical Building Code and will be referred to herein as “the CHBC.”
8-101.2 Purpose. The purpose of the CHBC is to provide regulations for the preservation, restoration, rehabilitation, relocation or reconstruction of buildings or properties designated as qualified historical buildings or properties (as defined in Chapter 8-2). The CHBC is intended to provide solutions for the preservation of qualified historical buildings or properties, to promote sustainability, to provide access for persons with disabilities, to provide a cost-effective approach to preservation, and to provide for the reasonable safety of the occupants or users. The CHBC requires enforcing agencies to accept solutions that are reasonably equivalent to the regular code (as defined in Chapter 8-2) when dealing with qualified historical buildings or properties.
8-101.3 Intent. The intent of the CHBC is to facilitate the preservation and continuing use of qualified historical buildings or properties while providing reasonable safety for the building occupants and access for persons with disabilities.
SECTION 8-102 — APPLICATION
8-102.1 Application. The CHBC is applicable to all issues regarding code compliance for qualified historical buildings or properties. The CHBC may be used in conjunction with the regular code to provide solutions to facilitate the preservation of qualified historical buildings or properties. The CHBC shall be used by any agency with jurisdiction and whenever compliance with the code is required for qualified historical buildings or properties.
- State or local enforcing agency. The state or local enforcing agency shall apply the provisions of the CHBC in permitting repairs, alterations and additions necessary for the preservation, restoration, reconstruction, rehabilitation, relocation or continued use of a qualified historical building or property when so elected by the private property owner.
- State agencies. All state agencies shall apply the provisions of the CHBC in permitting repairs, alterations and additions necessary for the preservation, restoration, rehabilitation, safety, relocation, reconstruction or continued use of qualified historical buildings or properties.
8-102.1.1 Additions, alterations and repairs. It is the intent of the CHBC to allow nonhistorical expansion or addition to a qualified historical building or property, provided nonhistorical additions shall conform to the requirements of the regular code (as defined in Chapter 8-2).
8-102.1.2 Relocation. Relocated qualified historical buildings or properties shall be sited to comply with the regular code or with the solutions listed in the CHBC. Nonhistorical new construction related to relocation shall comply with the regular code. Reconstruction and restoration related to relocation is permitted to comply with the provisions in the CHBC.
8-102.1.3 Change of occupancy. For change of use or occupancy, see Chapter 8-3, Use and Occupancy.
8-102.1.4 Continued use. Qualified historical buildings or properties may have their existing use or occupancy continued if such use or occupancy conformed to the code or to the standards of construction in effect at the time of construction, and such use or occupancy does not constitute a distinct hazard to life safety as defined in the CHBC.
8-102.1.5 Unsafe buildings or properties. When a qualified historical building or property is determined to be unsafe as defined in the regular code, the requirements of the CHBC are applicable to the work necessary to correct the unsafe conditions. Work to remediate the buildings or properties need only address the correction of the unsafe conditions, and it shall not be required to bring the entire qualified historical building or property into compliance with regular code.
Frequently asked questions
When does the CHBC allow me to remove a required one‑hour occupancy separation?
You may omit a required one‑hour occupancy separation when the qualified historical building is provided with an automatic sprinkler system throughout the building, per § 8‑302.3.
If a required separation is 2 hours, what exactly is required to reduce it to 1 hour?
Install an automatic sprinkler system throughout the building; provide a one‑hour fire‑resistive separation with all openings protected by ≥ 3/4‑hour fire‑resistive self‑closing or automatic‑closing assemblies that actuate on products of combustion, per § 8‑302.3.
Do door closers have to respond to smoke detectors?
Yes — doors equipped with automatic‑closing devices must be of a type that will function upon activation of a device which responds to products of combustion other than heat, per § 8‑302.3.
Which sprinkler standard do I use to meet the “sprinkler system throughout” requirement?
Refer to § 8‑410.2, which identifies the applicable NFPA standards (e.g., NFPA 13R for buildings up to four stories, NFPA 13 for higher floors) when CHBC requires sprinklers. Confirm the correct standard for your building height and configuration.
Where do I find the technical details for fire‑resistive assemblies I plan to use?
See Chapter 8‑4 (fire protection) and related sections such as § 8‑404 for historic assembly guidance (e.g., wood lath & plaster ratings); § 8‑302.6 directs you to Chapter 8‑4 for those details.
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