CHBC · California Historical Building Code
What CHBC residential standards apply to historic dwellings?
If your property is a qualified historical building used as a residence, the CHBC applies: the local/state enforcing agency must accept reasonably equivalent alternatives to the regular code so you can preserve historical features while still providing a reasonable level of life‑safety (see **§ 8-303.1–§ 8-303.3**) .
Last reviewed: July 6, 2026
What the code requires — 2-4 sentences
The California Historical Building Code (CHBC) sets out a performance‑oriented, preservation‑focused approach for qualified historical buildings used as residences. The CHBC requires enforcing agencies to accept any reasonably equivalent alternative to the regular code when dealing with qualified historical buildings and properties (§ 8-303.1) . Its intent is to preserve the integrity of a qualified historical building while still providing a reasonable degree of life‑safety for occupants (§ 8-303.2) . The section applies to all qualified historical buildings used for human habitation; units used only for display or public use with no residential use are excluded (§ 8-303.3) .
If a building is a qualified historical building and is used for human habitation, the CHBC applies and the enforcing agency must accept reasonably equivalent alternatives to the regular code to preserve historic integrity (see § 8-303.1–8-303.3) .
Requirements in detail
Core rules (plain language tied to the code)
- The CHBC exists to provide alternate regulations for qualified historical residential buildings so preservation and safety can be balanced (§ 8-303.1, § 8-303.2) .
- The CHBC is applicable when the building is a qualified historical building and is used for human habitation; structures intended only for display or public (nonresidential) use are not required to comply with this residential section (§ 8-303.3) .
- Enforcement: local or state enforcing agencies must accept reasonably equivalent alternatives to the regular code standards when applied to qualified historical residential buildings (§ 8-303.1) .
Decision table — when and how these rules apply
| Decision question | Decision value / threshold | Code Reference |
|---|---|---|
| Is the building a qualified historical building? | Yes → CHBC applies for preservation solutions | § 8-303.1 |
| Is the building used for human habitation? | Yes → Residential provisions of CHBC apply; No → § 8-303.3 exemption | § 8-303.3 |
| Must the enforcing agency accept alternative approaches? | Yes — any reasonably equivalent alternative to regular code is required to be accepted | § 8-303.1 |
| What is the overriding purpose? | Preserve integrity while maintaining a reasonable degree of occupant life‑safety | § 8-303.2 |
How to use the three sections together
- First confirm the property is a qualified historical building and that it will be used for human habitation — that determines applicability under § 8-303.3 .
- If applicable, the CHBC’s purpose and intent ( § 8-303.1 and § 8-303.2) guide the approach: preserve character‑defining features while accepting equivalent safety solutions instead of strict regular‑code compliance .
- All proposed solutions should therefore be framed and justified as "reasonably equivalent" in life‑safety performance to the regular code, so the enforcing agency can accept them under § 8-303.1 .
Exceptions & special cases
- Non‑residential historic spaces (for example, dwelling units intended only for display or public exhibit) do not need to comply with the residential provisions in this section — see § 8-303.3 .
- The CHBC is performance‑based and allows alternatives; however, it does not eliminate the enforcing agency’s authority to require remediation of distinct hazards to life safety (the CHBC’s intent is preservation balanced by reasonable safety) (§ 8-303.2) .
- Where additional, specific residential standards exist elsewhere in Part 8 (for example, room size, light/ventilation, exits), they may be applied in concert with Chapter 8-3 depending on the project—see Related Provisions below for sections addressing those details (these are separate sections of the CHBC) file.
Common mistakes
- Assuming CHBC always requires less work: the CHBC permits alternative solutions but still requires correction of distinct life‑safety hazards — don’t ignore safety because a building is historic (§ 8-303.2) .
- Failing to confirm the property is qualified as historic: the CHBC only applies to qualified historical buildings; properties must meet the definition and designation criteria to use Part 8, otherwise regular code applies (see CHBC definitions and qualification rules) .
- Treating display‑only historic units as residential: if a unit is only for exhibit/public use and there is no residential occupancy, § 8-303.3 excludes it from the residential requirements — verify actual use before applying CHBC residential rules .
- Not documenting the "reasonably equivalent" rationale: because the CHBC relies on acceptance of alternative solutions, provide clear performance justification to the enforcing agency per § 8-303.1 .
Worked example — applying the rule with numbers
Scenario: A city official reviews a permit to renovate a three‑unit, 1890 building listed on the local historic register. All three units remain rental dwelling units used for human habitation.
Step 1 — Applicability check:
- Is the building a qualified historical building listed locally? Yes → CHBC residential chapter applies (§ 8-303.3) .
Step 2 — Regulatory approach:
- The owner proposes installing a modern fire‑sprinkler system and upgrading egress illumination rather than reconstructing original stair geometry to meet full regular‑code stair dimensions.
- Under § 8-303.1, the enforcing agency should accept the proposed reasonably equivalent alternative (sprinkler + lighting) if it provides equivalent life‑safety protection, because the CHBC’s purpose is to allow preservation‑sensitive solutions while maintaining safety (§ 8-303.2) .
Step 3 — Outcome:
- If the agency documents that the sprinkler/lighting package achieves equivalent life safety for the three residential units, it may approve the alternative under CHBC; if not, the agency may negotiate additional measures. The key legal basis is § 8-303.1–§ 8-303.3 .
Related provisions
- § 8-303.5 — Room dimensions (minimum 50 square feet for sleeping rooms; average ceiling height 7 feet) — applicable residential detail if the enforcing agency invokes it .
- § 8-303.6 — Light and ventilation (windows in habitable rooms 6% of floor area or 6 square feet minimum; sleeping room windows shall be openable) .
- § 8-303.7 — Alteration and repair — allows retention/replacement of original materials/methods if no life‑safety hazard is created .
- Chapter 8-4 (e.g., § 8-402) — Fire‑resistive construction alternatives and automatic sprinkler provisions that often interact with residential solutions under Chapter 8-3 .
- CHBC administration & applicability (e.g., § 8-102.1 — how CHBC is applied by agencies and when additions/alterations must conform to regular code) .
Code references
Grounded in the retrieved California Historical Building Code — click a citation to read the verbatim passage:
CHBC § 323-9843 High 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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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 § 8-302.6 High relevance — show source text
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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USE AND OCCUPANCY
8-303.5 Room dimensions. Rooms used for sleeping purposes may contain a minimum of 50 square feet (4.6 m [2] ) floor area, provided there is maintained an average ceiling height of 7 feet (2134 mm). Other habitable rooms need only be of adequate size to be functional for the purpose intended.
8-303.6 Light and ventilation. Windows in habitable rooms shall have an area of 6 percent of the floor area, or 6 square feet (0.56 m [2] ), whichever is greater. Windows in sleeping rooms shall be openable (see Section 8-503). Residential occupancies need not be provided with electrical lighting.
8-303.7 Alteration and repair. The alteration and repair of qualified historical buildings or properties may permit the replacement, retention and extension of original materials and the continued use of original methods of construction, provided a life safety hazard is not created or continued. Alterations and repairs shall be consistent with the CHBC.
The amount of alterations and repairs is not limited, provided there is no nonhistorical increase in floor area, volume or size of the building or property.
8-303.8 Exiting. See Chapter 8-5.
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8-4 FIRE PROTECTION
SECTION 8-401 — PURPOSE, INTENT AND SCOPE
8-401.1 Purpose. The purpose of this chapter is to provide regulations for fire protection of qualified historical buildings or properties. The CHBC requires enforcing agencies to accept any reasonably equivalent alternatives to the regular code when dealing with qualified historical buildings or properties.
8-401.2 Intent. The intent of the CHBC is to preserve the integrity of qualified historical buildings or properties while maintaining a reasonable degree of fire protection based primarily on the life safety of the occupants and firefighting personnel.
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 § 8-9 High relevance — show source text
Bolt spacing shall not
exceed 6 feet (1830 mm) on center and shall not be less than 12 inches (305 mm) on center.
6. Other masonry based on tests or other substantiated data.
7. Embedded bolts to be tested as specified in regular code standards.
8. Stresses given may be increased for combinations of loads as specified in the regular code.
9. Adhesives shall be approved by the enforcing agency and installed in accordance with the manufacturer’s recommendations. All drilling dust shall be removed from drilled
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8-9 MECHANICAL, PLUMBING AND ELECTRICAL REQUIREMENTS
SECTION 8-901 — PURPOSE, INTENT AND SCOPE
8-901.1 Purpose. The purpose of the CHBC is to provide regulations for the mechanical, plumbing and electrical systems of buildings designated as qualified historical buildings or properties. The CHBC requires enforcing agencies to accept any reasonable equivalent solutions to the regular code when dealing with qualified historical buildings or properties.
8-901.2 Intent. The intent of the CHBC is to preserve the integrity of qualified historical buildings or properties while providing a reasonable level of protection from fire, health and life safety hazards (hereinafter referred to as safety hazards) for the building occupants.
8-901.3 Scope. The CHBC shall be applied in conjunction with the regular code whenever compliance with the regular code is required for qualified historical buildings or properties.
8-901.4 Safety hazard. No person shall permit any safety hazard to exist on premises under their control, or fail to take immediate action to abate such hazard. Existing systems which constitute a safety hazard when operational may remain in place, provided they are completely and permanently rendered inoperative. Safety hazards created by inoperative systems shall not be permitted to exist. Requirements of the regular code concerning general regulations shall be complied with, except that the enforcing agency shall accept solutions which do not cause a safety hazard.
8-901.5 Energy conservation. Qualified historical buildings or properties covered by this part are exempted from compliance with energy conservation standards. When new nonhistorical lighting and space conditioning system components, devices, appliances and equipment are installed, they shall comply with the requirements of Title 24, Part 6, The California Energy Code, except where the historical significance or character-defining features are threatened.
SECTION 8-902 — MECHANICAL
8-902.1 General. Mechanical systems shall comply with the regular code unless otherwise modified by this chapter.
8-902.1.1 The provisions of the CHBC shall apply to the acceptance, location, installation, alteration, repair, relocation, replacement or addition of any heating, ventilating, air conditioning, domestic incinerators, kilns or miscellaneous heat-producing appliances or equipment within or attached to a historical building.
8-902.1.2 Existing systems which do not, in the opinion of the enforcing agency, constitute a safety hazard may remain in use.
8-902.1.3 The enforcing agency may approve any alternative to the CHBC which would achieve equivalent life safety.
8-902.2 Heating facilities. All dwelling-type occupancies covered under this chapter shall be provided with heating facilities. Woodburning or pellet stoves or fireplaces may be acceptable as heating facilities.
CHBC § 8-6 High relevance — show source text
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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. The provisions in the CHBC apply to local, state and federal
governments (Title II entities); alteration of commercial facilities and places of public
accommodation (Title III entities); and barrier removal in commercial facilities and places of
public accommodation (Title III entities). Except as noted in this chapter.Applies Applies Applies SECTION 8-602 — BASIC PROVISIONS
8-602.1 Regular code. The regular code for access for people with disabilities (Title 24, Part
2, Vol.1, Chapter 11B) shall be applied to qualified historical buildings or properties unless
strict compliance with the regular code will threaten or destroy the historical significance or
character-defining features of the building or property.
**8-602.2 Alternative provisions.**If the historical significance or character-defining features
are threatened, alternative provisions for access may be applied pursuant to this chapter,
provided the following conditions are met:
1.These provisions shall be applied only on an item-by-item or case-by-case basis.
2.Documentation is provided, including meeting minutes or letters, stating the reasons
for the application of the alternative provisions. Such documentation shall be retained
in the permanent file of the enforcing agency.Applies Applies Applies Section 8-603 — ALTERNATIVES
**8-603.1 Alternative minimum standards.**The alternative minimum standards for alter-
ations of qualified historical buildings or facilities are referenced in Section 202.5 of the_ 2010_
ADA Standards for Accessible Design, as incorporated and set forth in federal regulation 28
CFR Pt. 36.
**8-603.2 Entry.CHBC § 8-1002.1 High 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 § 8-303.6 Medium relevance — show source text
8-303.6 Light and ventilation. Windows in habitable rooms shall have an area of 6 percent of the floor area, or 6 square feet (0.56 m [2] ), whichever is greater. Windows in sleeping rooms shall be openable (see Section 8-503). Residential occupancies need not be provided with electrical lighting.
8-303.7 Alteration and repair. The alteration and repair of qualified historical buildings or properties may permit the replacement, retention and extension of original materials and the continued use of original methods of construction, provided a life safety hazard is not created or continued. Alterations and repairs shall be consistent with the CHBC.
The amount of alterations and repairs is not limited, provided there is no nonhistorical increase in floor area, volume or size of the building or property.
8-303.8 Exiting. See Chapter 8-5.
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8-4 FIRE PROTECTION
SECTION 8-401 — PURPOSE, INTENT AND SCOPE
8-401.1 Purpose. The purpose of this chapter is to provide regulations for fire protection of qualified historical buildings or properties. The CHBC requires enforcing agencies to accept any reasonably equivalent alternatives to the regular code when dealing with qualified historical buildings or properties.
8-401.2 Intent. The intent of the CHBC is to preserve the integrity of qualified historical buildings or properties while maintaining a reasonable degree of fire protection based primarily on the life safety of the occupants and firefighting personnel.
8-401.3 Scope. This chapter shall apply when required by the provisions of Section 8-102.
SECTION 8-402 — FIRE-RESISTIVE CONSTRUCTION
8-402.1 Exterior wall construction. The fire-resistance requirement for existing exterior walls and existing opening protection may be satisfied when an automatic sprinkler system designed for exposure protection is installed per the CHBC. The automatic sprinklers may be installed on the exterior with at least one sprinkler located over each opening required to be protected. Additional sprinklers shall also be distributed along combustible walls under the roof lines that do not meet the fire-resistive requirement due to relationship to property lines as required by regular code. Such sprinkler systems may be connected to the domestic water supply on the supply-main side of the building shut-off valve. A shut-off valve may be installed for the sprinkler system, provided it is locked in an open position.
8-402.2 One-hour construction. Upgrading an existing qualified historical building or property to one-hour fire-resistive construction and one-hour fire-resistive corridors shall not be required regardless of construction or occupancy when one of the following is provided:
- An automatic sprinkler system throughout. See Section 8-410 for automatic sprinkler systems.
- An approved life safety evaluation.
- Other alternative measures as approved by the enforcing agency.
8-402.3 Openings in fire-rated systems. Historical glazing materials and solid wood unrated doors in interior walls required to have one-hour fire rating may be approved when operable windows and doors are provided with appropriate smoke seals and when the area affected is provided with an automatic sprinkler system. See Section 8-410 for automatic sprinkler systems.
SECTION 8-403 — INTERIOR FINISH MATERIALS
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.
CHBC § 8-3 Medium 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 § 8-3 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.
4 2025 CALIFORNIA HISTORICAL BUILDING CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
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.
Frequently asked questions
Does the CHBC automatically exempt a historic house from regular building standards?
No. The CHBC provides alternative, preservation‑oriented regulations and requires enforcing agencies to accept reasonably equivalent alternatives (§ 8-303.1), but it does not automatically exempt life‑safety corrections; distinct hazards must be addressed per the CHBC’s intent to maintain reasonable safety (§ 8-303.2) .
When does the residential section of the CHBC not apply?
If the dwelling units are intended only for display or purely public use with no residential occupancy, § 8-303.3 says the residential requirements in this section need not apply .
Who decides whether an alternative is “reasonably equivalent”?
The local or state enforcing agency is responsible for application and enforcement; the CHBC also provides for State Historical Building Safety Board (SHBSB) review and appeals if needed (§ 8-303.1 and related administrative sections) file.
Must I bring the whole building to regular code when repairing one part?
No. The CHBC generally limits required work to that necessary to correct unsafe conditions or complete the proposed work; it does not mandate bringing the entire building into full regular‑code compliance for every repair (see CHBC application language and intent) .
Are there specific minimums for rooms and windows under CHBC residential rules?
Yes — separate CHBC residential subsections specify room and window minimums (e.g., § 8-303.5 and § 8-303.6) when those details are applied by the enforcing agency; those are related provisions to Chapter 8-3 file.
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