CHBC · California Historical Building Code
What is a "distinct hazard" and what actions are required?
If a historic building has a condition that creates an immediate danger to people or the public right‑of‑way, the CHBC calls that a **distinct hazard** and continued use is not permitted until the hazard is remediated; ordinary historic nonconformance alone is not a distinct hazard, and required work is typically limited to correcting the unsafe condition rather than full modernization.
Last reviewed: July 6, 2026
What the code requires — 2-4 sentences
A distinct hazard is any clear and evident condition that is an immediate danger to the safety of the occupants or public right of way. This is the CHBC definition in § 8-201.
A qualified historical building may continue its existing use only if that use “does not constitute a distinct hazard to life safety,” per § 8-102.1.4. If a condition is a distinct hazard (or an unsafe condition under the regular code), the CHBC permits corrective work limited to remediating the unsafe condition rather than forcing full code compliance for the entire building.
A plain-English rule: if a condition is an immediate danger to people or the public way, it is a distinct hazard — continued use is not allowed until the hazard is corrected. (See § 8-201 and § 8-102.1.4.)
Requirements in detail
Core legal elements (what makes something a distinct hazard)
- Immediate danger to occupants or the public right-of-way — the essential threshold in § 8-201.
- Not every code nonconformance is a distinct hazard — lack of current regular-code compliance by itself does not prove a distinct hazard. § 8-201 makes this explicit.
- Continued use of a historical building is permitted only if the existing use does not constitute a distinct hazard to life safety, per § 8-102.1.4.
- When a building is determined unsafe under the regular code, the CHBC limits required work to correcting the unsafe conditions (it does not require bringing the whole building up to full regular-code compliance) — see § 8-102.1.5.
Decision-relevant dimensions (quick table)
| Decision dimension | What to look for | Action trigger | Code reference |
|---|---|---|---|
| Immediate danger to life/public right-of-way | Evidence of imminent collapse, major structural failure, large openings to the street, fire conditions that threaten egress | If present → distinct hazard found; remediate or close area | § 8-201 |
| Nonconformance with current regular code | Existing features that predate current code (narrow stairs, historic balusters, old wiring) | Nonconformance alone ≠ distinct hazard; needs analysis of risk | § 8-201 |
| Continued use / occupancy | Whether existing use matched historic standards and whether occupants are endangered | Continued use allowed only if it does not constitute a distinct hazard | § 8-102.1.4 |
| Unsafe building under regular code | Conditions the regular code would declare unsafe | CHBC work need only correct the unsafe condition (not full compliance) | § 8-102.1.5 |
| Distinct fire hazard (special action) | Building that “constitutes a distinct fire hazard” | May be brought into compliance by installing automatic sprinkler or approved life-safety system | § 8-410.1 |
What actions are required (how enforcing agencies typically act)
- Confirm whether the condition rises to a distinct hazard (immediate danger). The definition and scope are at § 8-201.
- If continued use is in question, apply § 8-102.1.4: existing use may be continued only if it does not create a distinct hazard. If it does, the enforcing agency will require correction or limit occupancy.
- If the condition is an unsafe building under the regular code, remedial work is limited to correcting those unsafe conditions (CHBC does not require full regular-code retrofits for the entire building). See § 8-102.1.5.
- For distinct fire hazards, the CHBC identifies sprinkler or approved life‑safety systems as an accepted path to compliance (see § 8-410.1).
Exceptions & special cases
- Historical features that do not meet present-day dimensional requirements (e.g., narrow stairs, historically low guardrail heights) are allowed to remain unless, in the enforcing agency’s opinion, they constitute a distinct hazard (see § 8-502.3).
- Noncompliance alone is not enough: many archaic or historic methods/materials may remain in place if the enforcing agency determines they do not create a safety hazard (see related CHBC provisions on accepting alternatives). § 8-201 clarifies this.
- When an imminent emergency exists (immediate peril to life, health, property), other review or appeal processes (SHBSB/SHBC appeals) still apply per CHBC administration clauses cited in definitions. § 8-201 notes appeals remain applicable.
Common mistakes
- Treating every historical nonconformance as a distinct hazard. The code explicitly says that failure to meet current regular codes does not automatically equal a distinct hazard (see § 8-201).
- Failing to document the analysis that led to a determination that something is or is not a distinct hazard. The CHBC expects enforcing agencies to make determinations (and appeals remain available).
- Confusing “unsafe under regular code” with “distinct hazard.” They overlap (both affect safety) but have different procedural effects under the CHBC: remediation for unsafe conditions can be limited in scope under § 8-102.1.5.
- Assuming a single technical fix (e.g., sprinklers) always solves a distinct hazard without consulting the enforcing agency — some hazards require other measures or an approved life-safety evaluation. See § 8-410.1.
Worked example — concrete scenario
Scenario: A three‑story historical boarding house (built 1905) has original single‑run stairs. The top landing has a loose tread; inspection shows a 2‑inch deflection under normal step load and a missing section of handrail over a 6‑foot run. The building otherwise predates modern code but has historically conforming egress paths.
Step-by-step application:
- Apply the definition: is there an immediate danger to occupants or the public way? A tread deflecting 2 inches under normal load and a missing handrail over a 6‑ft run present an immediate fall/injury risk to occupants — this is likely a distinct hazard under § 8-201.
- Because the condition likely constitutes a distinct hazard, continued use as-is is not permitted under § 8-102.1.4; the enforcing agency may require corrective measures or limit occupancy until corrected.
- The owner’s required work: repair or replace the loose tread and restore the handrail. Under § 8-102.1.5, the CHBC allows the enforcing agency to require only the work necessary to correct these unsafe conditions (it does not compel full modernization of all stairs).
- Documentation: the enforcing agency should document why the condition is a distinct hazard and the scope of required work; the owner can use CHBC appeal processes if there is disagreement (see CHBC administration/appeal provisions referenced in § 8-201).
Related provisions (select CHBC sections)
- § 8-201 — Definitions (includes Distinct Hazard).
- § 8-102.1.4 — Continued use: existing use may continue only if it does not constitute a distinct hazard.
- § 8-102.1.5 — Unsafe buildings: CHBC work limited to correcting unsafe conditions.
- § 8-410.1 — Automatic sprinkler / life safety systems as an accepted path when a building “constitutes a distinct fire hazard.”
- § 8-502.3 — Existing stairs allowed where enforcing agency determines they do not constitute a distinct hazard.
Code references
Grounded in the retrieved California Historical Building Code — click a citation to read the verbatim passage:
CHBC § 8-2 High relevance — show source text
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8-2 DEFINITIONS
SECTION 8-201 — DEFINITIONS
For the purpose of the CHBC, certain terms and phrases, words and their derivatives shall be construed as specified in this chapter. Additional definitions and/or terms may appear in the various other chapters relative to terms or phrases primarily applicable thereto. Any reference to “authority having jurisdiction” does not necessarily preclude the appellate process of Section 8-104.3.
ADDITION. A nonhistorical extension or increase in floor area or height of a building or property.
ALTERATION. A modification to a qualified historical building or property that affects the usability of the building or property, or part thereof. Alterations include, but are not limited to, remodeling, renovation, rehabilitation, reconstruction, historical restoration, changes or rearrangement of the structural parts or elements, and changes or rearrangements in the plan configuration of walls and full-height partitions.
BUILDING STANDARD. Any guideline, regulation or code that may be applied to a qualified historical building or property.
CHARACTER-DEFINING FEATURE. Those visual aspects and physical elements that comprise the appearance of a historical building or property, and that are significant to its historical, architectural and cultural values, including the overall shape of the historical building or property, its materials, craftsmanship, decorative details, interior spaces and features, as well as the various aspects of its site and environment.
CULTURAL RESOURCE. Building, site, property, object or district evaluated as having significance in prehistory or history.
DISTINCT HAZARD. Any clear and evident condition that exists as an immediate danger to the safety of the occupants or public right of way. Conditions that do not meet the requirements of current regular codes and ordinances do not, of themselves, constitute a distinct hazard. Section 8-104.3, SHBC appeals, remains applicable.
ENFORCING AGENCY, Authority Having Jurisdiction, Local Agency with Jurisdiction. An entity with the responsibility for regulating, enforcing, reviewing or otherwise that exerts control of or administration over the process of granting permits, approvals, decisions, variances, appeals for qualified historical buildings or properties.
EXIT LADDER DEVICE. An exit ladder device is a permanently installed, fixed, folding, retractable or hinged ladder intended for use as a means of emergency egress from areas of the second or third stories. Unless approved specifically for a longer length, the ladder shall be limited to 25 feet (7620 mm) in length. Exit ladders are permitted where the area served by the ladder has an occupant load less than 10 persons.
FIRE HAZARD. Any condition which increases or may contribute to an increase in the hazard or menace of fire to a greater degree than customarily recognized by the authority having jurisdiction, or any condition or act which could obstruct, delay, hinder or interfere with the operations of firefighting personnel or the egress of occupants in the event of fire. Section 8-104.3, SHBC appeals, remains applicable.
HISTORICAL FABRIC OR MATERIALS. Original and later-added historically significant construction materials, architectural finishes or elements in a particular pattern or configuration which form a qualified historical property, as determined by the authority having jurisdiction.
HISTORICAL SIGNIFICANCE. Importance for which a property has been evaluated and found to be historical, as determined by the authority having jurisdiction.
CHBC § 8.4. Medium relevance — show source text
accuracy. 2. If a tie-back anchor initially fails the testing requirements, the anchor shall be permitted to be re-grouted and retested. If the anchor continues to fail, the followings steps shall be taken: a. The contractor shall determine the cause of failure: (variations of the soil conditions, installation methods, materials, etc.).
b. The contractor shall propose a solution to remedy the problem. The proposed solution will need to be reviewed and approved by geotechnical engineer, shoring design engineer and the building official. 3. After a satisfactory test, each anchor shall be locked off in accordance with PTI Recommendations for Prestressed Rock and Soil Anchors Section 8.4.
4. The shoring design engineer shall specify design loads for each anchor.
1812.5 Construction: The construction procedure shall address the following: 1. Holes drilled for piles/tie-back anchors shall be done without detrimental loss of ground, sloughing or caving of materials and without endangering previously installed shoring members or existing foundations. 2. Drilling of earth anchor shafts for tie-backs shall occur when the drill bench reaches 2 to 3 feet below the level of the tie-back pockets. 3. Casing or other methods shall be used where necessary to prevent loss of ground and collapse of the hole. 4. Drill cuttings from the earth anchor shaft shall be removed prior to anchor installation. 5. Unless tremie methods are used, all water and loose materials shall be removed from the holes prior to installing piles/tie- backs.
6. Tie-back anchor rods with attached centralizing devices shall be installed into the shaft or through the drill casing. Centralizing devices shall not restrict movement of the grout. 7. After lagging installation, voids between lagging and soil shall be backfilled immediately to the full height of lagging. 8. The soldier piles shall be placed within specified tolerances in the drilled hole and braced against displacement during grout- ing. Shafts shall be filled with concrete up to the elevation shown on the construction documents. The remainder of the shaft shall be permitted to be filled with controlled low-strength material (CLSM), when permitted by the construction documents.
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SOILS AND FOUNDATIONS
Excavation for lagging shall not be started until concrete has achieved sufficient strength for all anticipated loads as deter- mined by the shoring design engineer. 9. Where boulders and/or cobbles have been identified in the geotechnical reports, the contractor shall be prepared to address boulders and/or cobbles that may be encountered during the drilling of soldier piles and tie-back anchors. 10. The grouting equipment shall produce grout free of lumps and indispensed cement. The grouting equipment shall be sized to enable the grout to be pumped in continuous operation. The mixer shall be capable of continuously agitating the grout. 11. The quantity of grout and grout pressure shall be recorded. The grout pressure shall be controlled to prevent excessive heave in soils or fracturing rock formations. 12. If post-grouting is required, post-grouting operation shall be performed after initial grout has set for 24 hours in the bond _length only.
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.
CHBC § 8-104.3 Medium relevance — show source text
ENFORCING AGENCY, Authority Having Jurisdiction, Local Agency with Jurisdiction. An entity with the responsibility for regulating, enforcing, reviewing or otherwise that exerts control of or administration over the process of granting permits, approvals, decisions, variances, appeals for qualified historical buildings or properties.
EXIT LADDER DEVICE. An exit ladder device is a permanently installed, fixed, folding, retractable or hinged ladder intended for use as a means of emergency egress from areas of the second or third stories. Unless approved specifically for a longer length, the ladder shall be limited to 25 feet (7620 mm) in length. Exit ladders are permitted where the area served by the ladder has an occupant load less than 10 persons.
FIRE HAZARD. Any condition which increases or may contribute to an increase in the hazard or menace of fire to a greater degree than customarily recognized by the authority having jurisdiction, or any condition or act which could obstruct, delay, hinder or interfere with the operations of firefighting personnel or the egress of occupants in the event of fire. Section 8-104.3, SHBC appeals, remains applicable.
HISTORICAL FABRIC OR MATERIALS. Original and later-added historically significant construction materials, architectural finishes or elements in a particular pattern or configuration which form a qualified historical property, as determined by the authority having jurisdiction.
HISTORICAL SIGNIFICANCE. Importance for which a property has been evaluated and found to be historical, as determined by the authority having jurisdiction.
IMMINENT THREAT. Any condition within or affecting a qualified historical building or property which, in the opinion of the authority having jurisdiction, would qualify a building or property as dangerous to the extent that the life, health, property or safety of the public, its occupants or those performing necessary repair, stabilization or shoring work are in immediate peril due to conditions affecting the building or property. Potential hazards to persons using, or improvements within, the right-of-way may not be construed to be “imminent threats” solely for that reason if the hazard can be mitigated by shoring, stabilization, barricades or temporary fences.
INTEGRITY. Authenticity of a building or property’s historical identity, evidenced by the survival of physical characteristics that existed during the property’s historical or prehistorical period of significance.
LIFE SAFETY EVALUATION. An evaluation of the life safety hazards of a qualified historical building or property based on procedures similar to those contained in NFPA 909, Standard for the Protection of Cultural Resources, Appendix B, Fire Risk Assessment in Heritage Premises.
LIFE SAFETY HAZARD. See Distinct Hazard.
PERIOD OF SIGNIFICANCE. The period of time when a qualified historical building or property was associated with important events, activities or persons, or attained the characteristics for its listing or registration.
PRESERVATION. The act or process of applying measures necessary to sustain the existing form, integrity and materials of a qualified historical building or property. Work, including preliminary measures to protect and stabilize the property, generally focuses upon the ongoing maintenance and repair of historic materials and features rather than extensive replacement and new construction. New exterior additions are not within the scope of this treatment; however, the limited and sensitive upgrading of mechanical,
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DEFINITIONS
electrical and plumbing systems and other code-related work to make properties functional is appropriate within a preservation project.
CHBC § 8-5 Medium relevance — show source text
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8-5 MEANS OF EGRESS
SECTION 8-501 — PURPOSE, INTENT AND SCOPE
8-501.1 Purpose. The purpose of this chapter is to establish minimum means of egress regulations for qualified historical buildings or properties. The CHBC requires enforcing agencies to accept reasonably equivalent alternatives to the means of egress requirements in the regular code.
8-501.2 Intent. The intent of these regulations is to provide an adequate means of egress.
8-501.3 Scope. Every qualified historical building or portion thereof shall be provided with exits as required by the CHBC when required by the provisions of Section 8-102.
SECTION 8-502 — GENERAL
8-502.1 General. The enforcing agency shall grant reasonable exceptions to the specific provisions of applicable egress regulations where such exceptions will not adversely affect life safety.
8-502.2. Existing door openings and corridor widths of less than dimensions required by regular code shall be permitted where there is sufficient width and height for the occupants to pass through the opening or traverse the exit.
8-502.3 Stairs. Existing stairs having risers and treads or width at variance with the regular code are allowed if determined by the enforcing agency to not constitute a distinct hazard. Handrails with nonconforming grip size or extensions are allowed if determined by the enforcing agency to not constitute a distinct hazard.
8-502.4 Main entry doors. The front or main entry doors need not be rehung to swing in the direction of exit travel, provided other means or conditions of exiting, as necessary to serve the total occupant load, are provided.
8-502.5 Existing fire escapes. Existing previously approved fire escapes and fire escape ladders shall be acceptable as one of the required means of egress, provided they extend to the ground and are easily negotiated, adequately signed and in good working order. Access shall be by an opening having a minimum width of 29 inches (737 mm) when open with a sill no more than 30 inches (762 mm) above the adjacent floor, landing or approved step.
8-502.6 New fire escapes and fire escape ladders. New fire escapes and fire escape ladders which comply with this section shall be acceptable as one of the required means of egress. New fire escapes and new fire escape ladders shall comply with the following:
- Access from a corridor shall not be through an intervening room.
- All openings within 10 feet (3048 mm) shall be protected by three-fourths-hour fire assemblies. When located within a recess or vestibule, adjacent enclosure walls shall be of not less than one-hour fire-resistive construction.
- Egress from the building shall be by a clear opening having a minimum dimension of not less than 29 inches (737 mm). Such openings shall be openable from the inside without the use of a key or special knowledge or effort. The sill of an opening giving access shall not be more than 30 inches (737 mm) above the floor, step or landing of the building or balcony.
- Fire escape stairways and balconies shall support the dead load plus a live load of not less than 100 pounds per square foot (4.79 kN/m [2] ) and shall be provided with a top and intermediate handrail on each side. The pitch of the stairway shall not exceed 72 degrees with a minimum width of 18 inches (457 mm).
CHBC § 8-410.3 Medium relevance — show source text
Buildings with floors above 75 feet, NFPA 13.
When the building is free standing or with property line separation, two floors and 1500 square feet per floor or less, NFPA 13D.
For exterior wall and opening protection. As required by this chapter.
Exception: When the automatic sprinkler systems are used to reach compliance using this code, in three or more occasions, NFPA 13D standard shall be increased to NFPA 13R standard, or NFPA 13R standard shall be increased to a NFPA 13 standard.
8-410.3 Automatic sprinkler systems shall not be used to substitute for or act as an alternate to the required number of exits from any facility. (See Chapter 8-5 for exiting requirements.)
8-410.4 An automatic sprinkler system shall be provided in all detention facilities.
SECTION 8-411 — OTHER TECHNOLOGIES
Fire alarm systems, smoke and heat detection systems, occupant notification and annunciation systems, smoke control systems and fire modeling, timed egress analysis and modeling, as well as other engineering methods and technologies may be accepted by the enforcing agency to address areas of nonconformance.
SECTION 8-412 — HIGH-RISE BUILDINGS
Qualified historical buildings having floors for human occupancy located more than 75 feet above the lowest floor level having building access shall conform to the provisions of the regular code for existing high-rise buildings as amended by the CHBC.
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8-5 MEANS OF EGRESS
SECTION 8-501 — PURPOSE, INTENT AND SCOPE
8-501.1 Purpose. The purpose of this chapter is to establish minimum means of egress regulations for qualified historical buildings or properties. The CHBC requires enforcing agencies to accept reasonably equivalent alternatives to the means of egress requirements in the regular code.
8-501.2 Intent. The intent of these regulations is to provide an adequate means of egress.
8-501.3 Scope. Every qualified historical building or portion thereof shall be provided with exits as required by the CHBC when required by the provisions of Section 8-102.
SECTION 8-502 — GENERAL
8-502.1 General. The enforcing agency shall grant reasonable exceptions to the specific provisions of applicable egress regulations where such exceptions will not adversely affect life safety.
8-502.2. Existing door openings and corridor widths of less than dimensions required by regular code shall be permitted where there is sufficient width and height for the occupants to pass through the opening or traverse the exit.
8-502.3 Stairs. Existing stairs having risers and treads or width at variance with the regular code are allowed if determined by the enforcing agency to not constitute a distinct hazard. Handrails with nonconforming grip size or extensions are allowed if determined by the enforcing agency to not constitute a distinct hazard.
8-502.4 Main entry doors. The front or main entry doors need not be rehung to swing in the direction of exit travel, provided other means or conditions of exiting, as necessary to serve the total occupant load, are provided.
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 § 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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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 § 8-102.1.6 Medium relevance — show source text
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. When a proposed design, material or method of construction is being considered by the enforcing agency, the agency chief, the building official or the local board of appeals may file a written request for opinion to the SHBSB for its consideration, advice or findings. In considering such request, the SHBSB may seek the advice of other appropriate private or public boards, individuals, or state or local agencies. The SHBSB shall, after considering all of the facts presented, including any recommendation of other appropriate boards, agencies or other parties, determine if, for the purpose intended, the proposal is reasonably equivalent to that allowed by these regulations in proposed design, material or method of construction, and it shall transmit such findings and its decision to the enforcing agency for its application. The Board may recover the costs of such reviews and shall report the decision in printed form, copied to the California Building Standards Commission.
8-104.2.1 State agencies. All state agencies with ownership of, or that act on behalf of state agency owners of, qualified historical buildings or properties, shall consult and obtain SHBSB review prior to taking action or making decisions or appeals that affect qualified historical buildings or properties, per Section 18961 of the Health and Safety Code.
8-104.2.2 Imminent threat. Where an emergency is declared and a qualified historical building or property is declared an imminent threat to life and safety, the state agency assessing such a threat shall consult with the SHBSB before any demolition is undertaken, per Section 18961 of the Health and Safety Code.
CHBC § 2.1.5 Medium relevance — show source text
In accordance with Section R301.2.1.5, where there is local historical data documenting structural damage to buildings due to topographic wind speed-up effects, the jurisdic-
tion shall fill in this part of the table with “YES.” Otherwise, the jurisdiction shall indicate “NO” in this part of the table.
l. In accordance with Figure R301.2(2), where there is local historical data documenting unusual wind conditions, the jurisdiction shall fill in this part of the table with “YES” and
identify any specific requirements. Otherwise, the jurisdiction shall indicate “NO” in this part of the table.
m.In accordance with Section R301.2.1.2 the jurisdiction shall indicate the wind-borne debris wind zone(s). Otherwise, the jurisdiction shall indicate “NO” in this part of the table.
n. The jurisdiction shall fill in these sections of the table to establish the design criteria using Table 1a or 1b from ACCA Manual J or established criteria determined by the jurisdiction.
o. The jurisdiction shall fill in this section of the allowable stress design table using the Ground Snow Loads in Figure R301.2(3).|For SI: 1 pound per square foot = 0.0479 kPa, 1 mile per hour = 0.447 m/s.
a. Where weathering requires a higher strength concrete or grade of masonry than necessary to satisfy the structural requirements of this code, the frost line depth strength required
for weathering shall govern. The weathering column shall be filled in with the weathering index, “negligible,” “moderate” or “severe” for concrete as determined from Figure
R301.2(1). The grade of masonry units shall be determined from ASTM C34, ASTM C55, ASTM C62, ASTM C73, ASTM C90, ASTM C129, ASTM C145, ASTM C216 or ASTM C652.
b. Where the frost line depth requires deeper footings than indicated in Figure R403.1(1), the frost line depth strength required for weathering shall govern. The jurisdiction shall
fill in the frost line depth column with the minimum depth of footing below finish grade.
c. The jurisdiction shall fill in this part of the table to indicate the need for protection depending on whether there has been a history of local subterranean termite damage.
d. The jurisdiction shall fill in this part of the table with the wind speed from the ultimate design wind speeds map [Figure R301.2(2)]. Wind exposure category shall be determined
on a site-specific basis in accordance with Section R301.2.1.4.
e. The jurisdiction shall fill in this section of the table to establish the design criteria using Table 10A from ACCA Manual J or established criteria determined by the jurisdiction.
f. The jurisdiction shall fill in this part of the table with the seismic design category determined from Section R301.2.2.1.
g. The jurisdiction shall fill in this part of the table with: the date of the jurisdiction’s entry into the National Flood Insurance Program (date of adoption of the first code or ordi-
nance for management of flood hazard areas); and the title and date of the currently effective Flood Insurance Study or other flood hazard study and maps adopted by the
authority having jurisdiction, as amended.
h.CHBC § 2.1.5 Medium relevance — show source text
The jurisdiction shall fill in this part of the table with the mean annual temperature from the National Climatic Data Center data table “Air Freezing Index-USA Method (Base 32°F).”
k. In accordance with Section R301.2.1.5, where there is local historical data documenting structural damage to buildings due to topographic wind speed-up effects, the jurisdic-
tion shall fill in this part of the table with “YES.” Otherwise, the jurisdiction shall indicate “NO” in this part of the table.
l. In accordance with Figure R301.2(2), where there is local historical data documenting unusual wind conditions, the jurisdiction shall fill in this part of the table with “YES” and
identify any specific requirements. Otherwise, the jurisdiction shall indicate “NO” in this part of the table.
m.In accordance with Section R301.2.1.2 the jurisdiction shall indicate the wind-borne debris wind zone(s). Otherwise, the jurisdiction shall indicate “NO” in this part of the table.
n. The jurisdiction shall fill in these sections of the table to establish the design criteria using Table 1a or 1b from ACCA Manual J or established criteria determined by the jurisdiction.
o. The jurisdiction shall fill in this section of the allowable stress design table using the Ground Snow Loads in Figure R301.2(3).|For SI: 1 pound per square foot = 0.0479 kPa, 1 mile per hour = 0.447 m/s.
a. Where weathering requires a higher strength concrete or grade of masonry than necessary to satisfy the structural requirements of this code, the frost line depth strength required
for weathering shall govern. The weathering column shall be filled in with the weathering index, “negligible,” “moderate” or “severe” for concrete as determined from Figure
R301.2(1). The grade of masonry units shall be determined from ASTM C34, ASTM C55, ASTM C62, ASTM C73, ASTM C90, ASTM C129, ASTM C145, ASTM C216 or ASTM C652.
b. Where the frost line depth requires deeper footings than indicated in Figure R403.1(1), the frost line depth strength required for weathering shall govern. The jurisdiction shall
fill in the frost line depth column with the minimum depth of footing below finish grade.
c. The jurisdiction shall fill in this part of the table to indicate the need for protection depending on whether there has been a history of local subterranean termite damage.
d. The jurisdiction shall fill in this part of the table with the wind speed from the ultimate design wind speeds map [Figure R301.2(2)]. Wind exposure category shall be determined
on a site-specific basis in accordance with Section R301.2.1.4.
e. The jurisdiction shall fill in this section of the table to establish the design criteria using Table 10A from ACCA Manual J or established criteria determined by the jurisdiction.
f. The jurisdiction shall fill in this part of the table with the seismic design category determined from Section R301.2.2.1.
g. The jurisdiction shall fill in this part of the table with: the date of the jurisdiction’s entry into the National Flood Insurance Program (date of adoption of the first code or ordi-
nance for management of flood hazard areas); and the title and date of the currently effective Flood Insurance Study or other flood hazard study and maps adopted by the
authority having jurisdiction, as amended.
h.CHBC § 8-409 Medium relevance — show source text
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
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.
Buildings with floors above 75 feet, NFPA 13.
When the building is free standing or with property line separation, two floors and 1500 square feet per floor or less, NFPA 13D.
For exterior wall and opening protection. As required by this chapter.
Exception: When the automatic sprinkler systems are used to reach compliance using this code, in three or more occasions, NFPA 13D standard shall be increased to NFPA 13R standard, or NFPA 13R standard shall be increased to a NFPA 13 standard.
8-410.3 Automatic sprinkler systems shall not be used to substitute for or act as an alternate to the required number of exits from any facility. (See Chapter 8-5 for exiting requirements.)
8-410.4 An automatic sprinkler system shall be provided in all detention facilities.
SECTION 8-411 — OTHER TECHNOLOGIES
Fire alarm systems, smoke and heat detection systems, occupant notification and annunciation systems, smoke control systems and fire modeling, timed egress analysis and modeling, as well as other engineering methods and technologies may be accepted by the enforcing agency to address areas of nonconformance.
SECTION 8-412 — HIGH-RISE BUILDINGS
Qualified historical buildings having floors for human occupancy located more than 75 feet above the lowest floor level having building access shall conform to the provisions of the regular code for existing high-rise buildings as amended by the CHBC.
8 2025 CALIFORNIA HISTORICAL BUILDING CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
8-5 MEANS OF EGRESS
Frequently asked questions
What exactly must be true before an enforcing agency calls something a “distinct hazard”?
The condition must be a clear and evident immediate danger to occupants or the public right-of-way. Mere lack of conformity with modern codes is not sufficient. See § 8-201.
If my historic building is found to have a distinct hazard, must I bring the whole building up to modern code?
No. When work is required because the building is unsafe, the CHBC allows work limited to correcting the unsafe/distinct‑hazard condition rather than full modernization of the entire building (see § 8-102.1.5).
Can installing sprinklers be used to address a distinct fire hazard?
Yes — the CHBC permits an automatic sprinkler system or an approved life-safety system as a way to comply when a building “constitutes a distinct fire hazard” (see § 8-410.1). Consult the enforcing agency about required sprinkler standards.
Who decides whether a condition is a distinct hazard?
The enforcing agency (authority having jurisdiction) makes the determination; CHBC also leaves appeals open under the Board/appeal process referenced in the code. See § 8-201 and the CHBC administration sections.
If I disagree with the enforcing agency’s finding, what recourse do I have?
The CHBC’s appeals/review procedures remain available (SHBSB/Board review per CHBC administrative provisions cited in the definitions and Section 8-104). See the administration/appeals provisions referenced in the CHBC.
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