CHBC · California Historical Building Code
What is the CHBC’s title, purpose and intent?
The CHBC (California Historical Building Code) is the state code that lets designated historical buildings be preserved, restored, or rehabilitated using alternative, reasonably equivalent solutions that protect historic character while still providing reasonable occupant safety and access.
Last reviewed: July 6, 2026
What the code requires
The regulations are titled the California Historical Building Code (the CHBC) — § 8-101.1.
The CHBC’s purpose is to provide alternative regulations for the preservation, restoration, rehabilitation, relocation or reconstruction of buildings or properties designated as qualified historical buildings or properties, and to promote sustainability, access for persons with disabilities, a cost‑effective approach to preservation, and reasonable safety for occupants. See § 8-101.2.
The intent is to facilitate preservation and continuing use of qualified historical buildings while still providing reasonable occupant safety and access for persons with disabilities. See § 8-101.3.
The CHBC is the state code that allows alternative, reasonably equivalent solutions to the regular code so historical buildings can be preserved and reused with reasonable safety and accessibility. See § 8-101.2 and § 8-101.3.
Requirements in detail
Short summary (plain English)
- The CHBC is an alternate, performance‑oriented code for properties that are designated as qualified historical buildings or properties. § 8-101.1–8-101.3 define the title, the broad purpose (preservation + sustainability + accessibility + cost‑effectiveness + reasonable safety) and the intent (facilitate preservation and continuing use while providing reasonable safety and access).
Decision‑relevant dimensions (quick reference)
| Decision dimension | What matters for application or decision | Code Reference |
|---|---|---|
| Name of regulations | Known as the California Historical Building Code (the CHBC) | § 8-101.1 |
| Eligible buildings/properties | Must be designated qualified historical buildings or properties (definition in Chapter 8‑2) | § 8-101.2 and definitions in Chapter 8‑2 |
| Primary purposes | Preservation / restoration / rehabilitation / relocation / reconstruction; promote sustainability, access, cost‑effectiveness, reasonable safety | § 8-101.2 |
| Safety standard | Provide reasonable safety for occupants (performance oriented; not automatic full waiver of life‑safety) | § 8-101.2, § 8-101.3 |
| Relationship to regular code | Enforcing agencies must accept solutions reasonably equivalent to the regular code when appropriate | § 8-101.2 |
| Who uses it | State and local enforcing agencies in permitting repairs, alterations, additions for qualified historical buildings (owner may elect CHBC use; see application rules) | § 8-102.1 |
How the three sections work together
- § 8-101.1 names the code (establishes the CHBC as the governing part).
- § 8-101.2 lists the purpose and policy goals (preservation, sustainability, access, cost‑effectiveness, reasonable safety; requires accepting reasonably equivalent solutions).
- § 8-101.3 states the intent: to facilitate continuing use while providing reasonable safety and accessibility.
Exceptions & special cases
- The CHBC applies only to designated qualified historical buildings or properties; it does not automatically apply to every old building. The CHBC’s scope and the qualification criteria are in Chapter 8‑2. Do not assume CHBC applies without the designation. § 8-101.2 and Chapter 8‑2.
- Use of the CHBC is coordinated with the regular code: the CHBC allows alternatives and requires acceptance of reasonably equivalent solutions, but it does not permit enforcing agencies to reduce life‑safety in critical public‑safety occupancies (see structural and other chapter limits). See § 8-101.2 and cross‑references in Chapters (e.g., structural limits in Chapter 8‑7).
- Some chapters (for example accessibility, structural, fire protection) include additional purpose/intent/scope language that narrows how alternatives are applied (e.g., accessibility alternatives require documentation and item‑by‑item review). See Chapter 8‑6 (accessibility) and Sections such as 8-602.2.
Common mistakes
- Thinking the CHBC automatically allows ignoring safety: the CHBC aims to provide reasonable safety, not to eliminate life‑safety requirements. See § 8-101.2 and § 8-101.3.
- Assuming any old building qualifies: a building must be designated a qualified historical building or property (see Chapter 8‑2). § 8-101.2 (purpose cites the definition in Chapter 8‑2).
- Expecting blanket waivers of the regular code: the CHBC requires enforcing agencies to accept reasonably equivalent solutions — not to accept unsafe or wholly non‑equivalent substitutions. § 8-101.2.
- Failing to document accessibility or alternative decisions: accessibility alternatives must be applied item‑by‑item with documentation as required elsewhere in the CHBC (see Chapter 8‑6).
Worked example
Scenario: A private owner of a 1906 townhouse listed on the local historic register wants to rehabilitate the building for continued residential use and to add an accessible entry. The owner elects to pursue work under the CHBC.
How the CHBC applies — step‑by‑step:
- Qualification check: Because the townhouse is on a local register it meets the definition of a qualified historical building or property (Chapter 8‑2). Apply CHBC provisions. § 8-101.2.
- Enforcement: The local enforcing agency applies the CHBC in permitting the rehabilitation — CHBC is used for repairs, alterations and additions necessary for preservation and continued use. § 8-102.1.
- Accessibility solution: If a standard ramp or doorway alteration would threaten the building’s character‑defining façade, the enforcing agency may accept an alternative, reasonably equivalent accessibility solution (for example, an interior lift or remote accessible entrance), provided documentation supports the choice and the alternative provides substantially equivalent access. The CHBC’s purpose and intent authorize accepting reasonably equivalent solutions while preserving historic character. § 8-101.2, § 8-101.3; see also Chapter 8‑6 (accessibility alternatives require documentation).
Note: The CHBC sections § 8-101.1–8-101.3 set the policy framework but do not prescribe specific numeric thresholds (e.g., ramp slopes or clearances); those technical details appear in the applicable chapters or the regular code when adopted or in accessibility alternatives rules. The CHBC enables alternative, case‑by‑case solutions consistent with its purpose and intent.
Related provisions
- § 8-102.1 — Application (when and how the CHBC is applied by enforcing agencies).
- § 8-102.1.1 — Additions, alterations and repairs (nonhistorical additions must meet the regular code).
- § 8-102.1.2 — Relocation (siting and reconstruction guidance).
- § 8-103.1 — Authority (enforcement by state or local enforcing agency).
- Chapter 8‑6 (e.g., § 8-602.2) — Accessibility alternatives and documentation requirements.
- Chapter 8‑7 (structural regulations) — purpose/intent/scope for structural alternates (see § 8-701.1–8-701.3).
Code references
Grounded in the retrieved California Historical Building Code — click a citation to read the verbatim passage:
CHBC § 8-101.1 High 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 § 8-1001 High 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 § 8-604 High relevance — show source text
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ACCESSIBILITY
SECTION 8-604 — EQUIVALENT FACILITATION
Use of other designs and technologies, or deviation from particular technical and scoping requirements, are permitted if the application of the alternative provisions contained in Section 8-603 would threaten or destroy the historical significance or characterdefining features of the historical building or property.
- Such alternatives shall be applied only on an item-by- item or a case-by-case basis.
- Access provided by experiences, services, functions, materials and resources through methods including, but not limited to, maps, plans, videos, virtual reality and related equipment, at accessible levels. The alternative design and/or technologies used will provide substantially equivalent or greater accessibility to, and usability of, the facility.
- The official charged with the enforcement of the standards shall document the reasons for the application of the design and/or technologies and their effect on the historical significance or character-defining features. Such documentation shall be in accordance with Section 8-602.2, Item 2, and shall include the opinion and comments of state or local accessibility officials, and the opinion and comments of representative local groups of people with disabilities. Such documentation shall be retained in the permanent file of the enforcing agency. Copies of the required documentation should be available at the facility upon request.
Note: For commercial facilities and places of public accommodation (Title III entities).
Equivalent facilitation for an element of a building or property when applied as a waiver of an ADA accessibility requirement will not be entitled to the Federal Department of Justice certification of this code as rebuttable evidence of compliance for that element.
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8-7 STRUCTURAL REGULATIONS
SECTION 8-701 — PURPOSE, INTENT AND SCOPE
8-701.1 Purpose. The purpose of the CHBC is to provide alternative regulations to the regular code for the structural safety of buildings designated as 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.
8-701.2 Intent. The intent of this chapter is to encourage the preservation of qualified historical buildings or structures while providing standards for a minimum level of building performance with the objective of preventing partial or total structural collapse such that the overall risk of life-threatening injury as a result of structural collapse is low.
8-701.3 Application. The alternative structural regulations provided by Section 8-705 are to be applied in conjunction with the regular code whenever a structural upgrade or reconstruction is undertaken for qualified historical buildings or properties.
SECTION 8-702 — GENERAL
8-702.1 The CHBC shall not be construed to allow the enforcing agency to approve or permit a lower level of safety of structural design and construction than that which is reasonably equivalent to the regular code provisions in occupancies which are critical to the safety and welfare of the public at large, including, but not limited to, public and private schools, hospitals, municipal police and fire stations and essential services facilities.
8-702.2 Nothing in these regulations shall prevent voluntary and partial seismic upgrades when it is demonstrated that such upgrades will improve life safety and when a full upgrade would not otherwise be required.
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 § 8-503 High relevance — show source text
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MEANS OF EGRESS
SECTION 8-503 — ESCAPE OR RESCUE WINDOWS AND DOORS
Basements in dwelling units and every sleeping room below the fourth floor shall have at least one openable window or door approved for emergency escape which shall open directly into a public street, public way, yard or exit court. Escape or rescue windows or doors shall have a minimum clear area of 3.3 square feet (0.31 m [2] ) and a minimum width or height dimension of 18 inches (457 mm) and be operable from the inside to provide a full, clear opening without the use of special tools.
SECTION 8-504 — RAILINGS AND GUARDRAILS
The height of railings and guard railings and the spacing of balusters may continue in their historical height and spacing unless a distinct hazard has been identified or created by a change in use or occupancy.
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8-6 ACCESSIBILITY
SECTION 8-601 — PURPOSE, INTENT AND 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 qualified 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.
- Provisions of this chapter do not apply to new construction or reconstruction/replicas of historical buildings.
- 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.
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:
- These provisions shall be applied only on an item-by-item or a case-by-case basis.
- 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.
SECTION 8-603 — ALTERNATIVES
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
holes prior to installation.|18 2025 CALIFORNIA HISTORICAL BUILDING CODE
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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 § 8-7 High relevance — show source text
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8-7 STRUCTURAL REGULATIONS
SECTION 8-701 — PURPOSE, INTENT AND SCOPE
8-701.1 Purpose. The purpose of the CHBC is to provide alternative regulations to the regular code for the structural safety of buildings designated as 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.
8-701.2 Intent. The intent of this chapter is to encourage the preservation of qualified historical buildings or structures while providing standards for a minimum level of building performance with the objective of preventing partial or total structural collapse such that the overall risk of life-threatening injury as a result of structural collapse is low.
8-701.3 Application. The alternative structural regulations provided by Section 8-705 are to be applied in conjunction with the regular code whenever a structural upgrade or reconstruction is undertaken for qualified historical buildings or properties.
SECTION 8-702 — GENERAL
8-702.1 The CHBC shall not be construed to allow the enforcing agency to approve or permit a lower level of safety of structural design and construction than that which is reasonably equivalent to the regular code provisions in occupancies which are critical to the safety and welfare of the public at large, including, but not limited to, public and private schools, hospitals, municipal police and fire stations and essential services facilities.
8-702.2 Nothing in these regulations shall prevent voluntary and partial seismic upgrades when it is demonstrated that such upgrades will improve life safety and when a full upgrade would not otherwise be required.
SECTION 8-703 — STRUCTURAL SURVEY
8-703.1 Scope. When a structure or portion of a structure is to be evaluated for structural capacity under the CHBC, it shall be surveyed for structural conditions by an architect or engineer knowledgeable in historical structures. The survey shall evaluate deterioration or signs of distress. The survey shall determine the details of the structural framing and the system for resistance of gravity and lateral loads. Details, reinforcement and anchorage of structural systems and veneers shall be determined and documented where these members are relied on for seismic lateral resistance.
8-703.2 The results of the survey shall be utilized for evaluating the structural capacity and for designing modifications to the structural system to reach compliance with this code.
8-703.3 Historical records. Past historical records of the structure or similar structures may be used in the evaluation, including the effects of subsequent alterations.
SECTION 8-704 — NONHISTORICAL ADDITIONS AND NONHISTORICAL ALTERATIONS
8-704.1 New nonhistorical additions and nonhistorical alterations which are structurally separated from an existing historical building or structure shall comply with regular code requirements.
8-704.2 New nonhistorical additions which impose vertical or lateral loads on an existing structure shall not be permitted unless the affected part of the supporting structure is evaluated and strengthened, if necessary, to meet regular code requirements.
Note: For use of archaic materials, see Chapter 8-8.
SECTION 8-705 — STRUCTURAL REGULATIONS
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 § 12.7 High relevance — show source text
Values are for strength level loads as defined in regular code standards.
2. Values may be adjusted for other fasteners when approved by the enforcing authority.
3. In addition to existing sheathing value.
4. Bolts to be1/2-inch (12.7 mm) minimum diameter.
5. Other bolt sizes, values and installation methods may be used provided a testing program is conducted in accordance with regular code standards. 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
holes prior to installation.|1. Values are for strength level loads as defined in regular code standards.
2. Values may be adjusted for other fasteners when approved by the enforcing authority.
3. In addition to existing sheathing value.
4. Bolts to be1/2-inch (12.7 mm) minimum diameter.
5. Other bolt sizes, values and installation methods may be used provided a testing program is conducted in accordance with regular code standards. 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
holes prior to installation.|18 2025 CALIFORNIA HISTORICAL BUILDING CODE
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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.
CHBC § 8-801 High relevance — show source text
SECTION 8-801 — PURPOSE, INTENT AND SCOPE
8-801.1 Purpose. The purpose of the CHBC is to provide regulations for the use of historical methods and materials of construction that are at variance with regular code requirements or are not otherwise codified, in buildings or structures designated as qualified historical buildings or properties. The CHBC require enforcing agencies to accept any reasonably equivalent alternatives to the regular code when dealing with qualified historical buildings or properties.
8-801.2 Intent. It is the intent of the CHBC to provide for the use of historical methods and materials of construction that are at variance with specific code requirements or are not otherwise codified.
8-801.3 Scope. Any construction type or material that is, or was, part of the historical fabric of a structure is covered by this chapter. Archaic materials and methods of construction present in a historical structure may remain or be reinstalled or be installed with new materials of the same class to match existing conditions.
SECTION 8-802 — GENERAL ENGINEERING APPROACHES
Strength values for archaic materials shall be assigned based upon similar conventional codified materials, or on tests as hereinafter indicated. The archaic materials and methods of construction shall be thoroughly investigated for their details of construction in accordance with Section 8-703. Testing shall be performed when applicable to evaluate existing conditions. The architect or structural engineer in responsible charge of the project shall assign allowable stresses or strength levels to archaic materials. Such assigned strength values shall not be greater than those provided for in the following sections without adequate testing, and shall be subject to the concurrence of the enforcing agency.
SECTION 8-803 — NONSTRUCTURAL ARCHAIC MATERIALS
Where nonstructural historical materials exist in uses which do not meet the requirements of the regular code, their continued use is allowed by this code, provided that any public health and life safety hazards are mitigated subject to the concurrence of the enforcing agency.
SECTION 8-804 — ALLOWABLE CONDITIONS FOR SPECIFIC MATERIALS
Archaic materials which exist and are to remain in qualified historical buildings or structures shall be evaluated for their condition and for loads required by this code. The structural survey required in Section 8-703 of the CHBC shall document existing conditions, reinforcement, anchorage, deterioration and other factors pertinent to establishing allowable stresses, strength levels and adequacy of the archaic materials. The remaining portion of this chapter provides additional specific requirements for commonly encountered archaic materials.
SECTION 8-805 — MASONRY
For adobe, see Section 8-806.
8-805.1 Existing solid masonry. Existing solid masonry walls of any type, except adobe, may be allowed, without testing, a maximum ultimate strength of 9 pounds per square inch (62.1 kPa) in shear where there is a qualifying statement by the architect or engineer that an inspection has been made, that mortar joints are filled and that both brick and mortar are reasonably good. The shear stress above applies to unreinforced masonry, except adobe, where the maximum ratio of unsupported height or length to thickness does not exceed 13, and where minimum quality mortar is used or exists. Wall height or length is measured to supporting or resisting elements that are at least twice as stiff as the tributary wall. Stiffness is based on the gross section. Shear stress may be increased by the addition of 10 percent of the axial direct stress due to the weight of the wall directly above.
CHBC § 8-303.6 High 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 § 8-3 High relevance — show source text
This shall include historical buildings or properties on, or determined eligible for, national, state or local historical registers or inventories, such as the National Register of Historic Places, California Register of Historical Resources, State Historical Landmarks, State Points of Historical Interest, and city or county registers, inventories or surveys of historical or architecturally significant sites, places or landmarks.
RECONSTRUCTION. The act or process of depicting, by means of new construction, the form, features and detailing of a nonsurviving site, landscape, building, property or object for the purpose of replicating its appearance at a specific period of time.
REGULAR CODE. The adopted regulations that govern the design and construction or alteration of nonhistorical buildings and properties within the jurisdiction of the enforcing agency.
REHABILITATION. The act or process of making possible a compatible use for qualified historical building or property through repair, alterations and additions while preserving those portions or features which convey its qualified historical, cultural or architectural values.
RELOCATION. The act or process of moving any qualified historical building or property or a portion of a qualified historical building or property to a new site, or a different location on the same site.
REPAIR. Renewal, reconstruction or renovation of any portion of an existing property, site or building for the purpose of its continued use.
RESTORATION. The act or process of accurately depicting the form, features and character of a qualified building or property as it appeared at a particular period of time by the means of the removal of features from other periods in its history and reconstruction of missing features from the restoration period. The limited and sensitive upgrading of mechanical, electrical and plumbing systems and other code-required work to make properties functional is appropriate within a restoration project.
STRUCTURE. That which is built or constructed, an edifice or a building of any kind, or any piece of work artificially built up or composed of parts joined together in some definite manner.
TREATMENT. An act of work to carry out preservation, restoration, stabilization, rehabilitation or reconstruction.
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8-3 USE AND OCCUPANCY
SECTION 8-301 — PURPOSE AND SCOPE
8-301.1 Purpose. The purpose of the CHBC is to provide regulations for the determination of occupancy classifications and conditions of use for qualified historical buildings or properties.
8-301.2 Scope. Every qualified historical building or property for which a permit or approval has been requested shall be classified prior to permit issuance according to its use or the character of its occupancy in accordance with the regular code and applicable provisions of this chapter.
SECTION 8-302 — GENERAL
8-302.1 Existing use. The use or character of occupancy of a qualified historical building or property, or portion thereof, shall be permitted to continue in use regardless of any period of time in which it may have remained unoccupied or in other uses, provided such building or property otherwise conforms to all applicable requirements of the CHBC.
8-302.2 Change in occupancy. The use or character of the occupancy of a qualified historical building or property may be changed from or returned to its historical use or character, provided the qualified historical building or property conforms to the requirements applicable to the new use or character of occupancy as set forth in the CHBC. Such change in occupancy shall not mandate conformance with new construction requirements as set forth in regular code.
Frequently asked questions
Who can use the CHBC?
Any owner of a qualified historical building or property may elect to use the CHBC; state and local enforcing agencies apply it when dealing with qualified historical buildings or properties. See § 8-101.2 and § 8-102.1.
Does the CHBC mean I can ignore modern safety codes?
No. The CHBC provides alternative regulations and requires accepting reasonably equivalent solutions that preserve historic character while providing reasonable safety and access. It does not permit reducing life‑safety in critical public‑safety occupancies. See § 8-101.2 and § 8-101.3.
What if an accessibility change would damage historic fabric?
The CHBC allows case‑by‑case alternatives and requires documentation when strict compliance with the regular accessibility code would threaten or destroy historical significance; alternatives must provide substantially equivalent access. See Chapter 8‑6 and § 8-101.2.
Are nonhistorical additions treated the same way?
Nonhistorical additions are allowed but must conform to the regular code; the CHBC intends to allow nonhistorical expansion only if the addition meets regular code requirements. See § 8-102.1.1.
Where are the definitions for “qualified historical building or property”?
Definitions are in Chapter 8‑2 (see the CHBC definitions section). § 8-101.2 refers to Chapter 8‑2 for the definition.
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