CHBC · California Historical Building Code

What is the CHBC purpose, intent and scope for archaic materials?

If your building is a qualified historical property, the CHBC’s archaic-materials chapter lets original historic materials stay or be reinstalled (or matched in-kind) and directs enforcing agencies to accept reasonable, equivalent alternatives instead of forcing regular-code solutions that would destroy historic fabric — see **§ 8-801.1**, **§ 8-801.2**, **§ 8-801.3**.

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Last reviewed: July 6, 2026

What the code requires — 2–4 sentences

The CHBC allows the continued use, reinstallation, or in-kind replacement of archaic materials in buildings designated as qualified historical buildings or properties and requires enforcing agencies to accept reasonably equivalent alternatives to the regular code when addressing such buildings. The code states this purpose in § 8-801.1 and frames the policy intent in § 8-801.2, while § 8-801.3 defines the chapter’s scope (what counts as archaic materials and what actions are allowed).

The single most important rule: the CHBC’s Chapter on archaic materials exists to permit historic methods and materials to remain or be reinstalled, and to require agencies to accept reasonably equivalent alternatives rather than force strict regular-code conformity. § 8-801.1

Requirements in detail

Core policy statements (plain language)

  • Purpose: Permit use of historical methods/materials that differ from the regular code and require agencies to accept reasonably equivalent alternatives when dealing with qualified historical properties. § 8-801.1
  • Intent: Facilitate use of historical materials or methods that are at variance with specific code requirements or are not codified. § 8-801.2
  • Scope: Covers “any construction type or material that is, or was, part of the historical fabric of a structure,” and expressly allows archaic materials and methods “to remain or be reinstalled or be installed with new materials of the same class to match existing conditions.” § 8-801.3

Decision-relevant dimensions (quick reference table)

Decision dimension Relevant value / rule Code Reference
Who it applies to Buildings/properties designated as qualified historical § 8-801.1, § 8-801.3
Allowed actions for archaic materials May remain, be reinstalled, or be installed with new materials of the same class to match existing § 8-801.3
Agency obligation Must accept reasonably equivalent alternatives to the regular code for qualified historical properties § 8-801.1
When to use CHBC Whenever code compliance is required for a qualified historical building/property and historical methods/materials are in play § 8-801.1, § 8-801.3
Relationship to other CHBC chapters This chapter provides the allowances; technical evaluation or testing may be required elsewhere in CHBC § 8-801.3 (cross-referenced in Chapter 8-8)

How to apply the sections together

  • First, confirm the building/property is a qualified historical resource (application of CHBC is limited to qualified properties). § 8-801.1
  • If archaic materials exist (original siding, historic brick, lime mortar, etc.), CHBC allows them to remain, be reinstalled, or be replaced in-kind with the same class of material. § 8-801.3
  • If the regular code would require a different approach, the enforcing agency must accept a reasonably equivalent alternative that respects the historic fabric. § 8-801.1

Exceptions & special cases

  • The text of § 8-801.1–.3 itself establishes policy but does not list numeric performance exceptions or detailed engineering limits — those detail sections appear elsewhere in Chapter 8-8 (e.g., engineering approaches, allowable conditions for specific materials). For engineering limits, testing procedures, or allowable stresses you must consult the subsequent sections (for example, strength values and testing are addressed in 8-802 and material-specific subsections). The purpose/intent/scope sections do not prescribe numerical thresholds. § 8-801.1–.3
  • The CHBC still defers to the enforcing agency’s judgement: while the agency must accept reasonably equivalent alternatives, it retains authority to require documentation or mitigation if a public safety hazard exists (this policy is reflected across the CHBC). § 8-801.1

Common mistakes

  • Treating the CHBC as an automatic blanket exemption. The CHBC allows historic materials to remain or be reinstalled, but it is not carte blanche to ignore safety — agencies accept reasonably equivalent solutions rather than automatic noncompliance. § 8-801.1
  • Confusing “may remain” with “must remain.” Owners and designers can choose in-kind work or otherwise, but when historic materials are used, the CHBC gives the legal framework to accept equivalent solutions. § 8-801.3
  • Looking for numeric performance values in these sections. Sections § 8-801.1–.3 set policy and scope — they do not give engineering numbers or test methods (see other Chapter 8-8 sections for tests/values). § 8-801.1–.3

Worked example — applying the rule

Scenario: A 1905 storefront on the local historic register has original wood clapboard siding (archaic material). The owner proposes to remove and reinstall the same style clapboard on a 200 ft² façade and to retain original lap joints where possible.

How CHBC applies:

  1. Confirm the building is a qualified historical property and CHBC applies. § 8-801.1
  2. Because the clapboard is part of the historical fabric, CHBC permits the clapboard to remain, be reinstalled, or be installed with new materials of the same class to match existing conditions — so in-kind replacement over 200 ft² is explicitly allowed in scope. § 8-801.3
  3. If the regular code would require a modern wall assembly incompatible with the historic appearance, the enforcing agency must accept a reasonably equivalent alternative that preserves the historic siding while achieving safety objectives (documentation of equivalency will be requested). § 8-801.1

Note: The sections at issue do not prescribe specific testing, nailing schedules, or allowable stresses for the siding — those technical requirements, if needed, are found elsewhere in Chapter 8-8 or may be established by the enforcing agency and qualified professionals. § 8-801.1–.3

Related provisions

  • § 8-802 — General engineering approaches (assigning strength values, testing, and investigation of archaic materials).
  • § 8-803 — Nonstructural archaic materials (continued use allowed provided health/life-safety hazards are mitigated).
  • § 8-804 — Allowable conditions for specific materials (evaluation and documentation requirements).
  • § 8-703 — Structural survey (used elsewhere in the CHBC to document existing conditions; structural evaluation may be required for materials relied on for resistance).

Code references

Grounded in the retrieved California Historical Building Code — click a citation to read the verbatim passage:

  • CHBC § 8-706.3 High relevance — show source text

    8-706.3 Load path. A complete and continuous load path, including connections, from every part or portion of the structure to the ground shall be provided for the required forces. It shall be verified that the structure is adequately tied together to perform as a unit when subjected to earthquake forces.

    8-706.4 Parapets. Parapets and exterior decoration shall be investigated for conformance with regular code requirements for anchorage and ability to resist prescribed seismic forces.

    An exception to regular code requirements shall be permitted for those parapets and decorations which are judged not to be a hazard to life safety.

    8-706.5 Nonstructural features. Nonstructural features of historical structure, such as exterior veneer, cornices and decorations, which might fall and create a life safety hazard in an earthquake, shall be evaluated. Their ability to resist seismic forces shall be verified, or the feature shall be strengthened with improved anchorage when appropriate.

    8-706.5.1 Partitions and ceilings of corridors and stairways serving an occupant load of 30 or more shall be investigated to determine their ability to remain in place when the building is subjected to earthquake forces.

    8-706.5.2 Seismic forces used to evaluate and improve nonstructural components and their anchorage, where required, shall comply with ASCE 41 or need not exceed 0.75 times the seismic forces prescribed by the requirements of the regular code.

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    8-8 ARCHAIC MATERIALS AND METHODS OF CONSTRUCTION

    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

  • 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 § 8-7 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 § 8-1001 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.

    1. 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.
    2. **State agencies.
  • 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.

    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.

    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 a 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.

    SECTION 8-603 — ALTERNATIVES

  • 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.|

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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 § 8-101.1 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.

    1. 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.
    2. 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 § 8-9 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.|

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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 Entities    		 Title III
    Private Entities    		 Title III
    Barrier Removal
    SECTION 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.

    2025 CALIFORNIA HISTORICAL BUILDING CODE 23

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

    24 2025 CALIFORNIA HISTORICAL BUILDING CODE

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

    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 Entities    		 Title III
    Private Entities    		 Title III
    Barrier Removal
    SECTION 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 § 8-8 High relevance — show source text

    CHAPTER 8-8 ARCHAIC MATERIALS AND METHODS OF

    CONSTRUCTION . . . . . . . . . . . . . . . . . . . . . . . 15

    Section

    8-801 Purpose, Intent and Scope . . . . . . . . . . . . . . . . . . . . . . 15 8-802 General Engineering Approaches. . . . . . . . . . . . . . . . . 15 8-803 Nonstructural Archaic Materials. . . . . . . . . . . . . . . . . . 15

    8-804 Allowable Conditions for Specific Materials . . . . . . . 15 8-805 Masonry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 8-806 Adobe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

    8-807 Wood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

    8-808 Concrete . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

    8-809 Steel and Iron . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

    8-810 Hollow Clay Tile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

    8-811 Veneers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

    8-812 Glass and Glazing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

    CHAPTER 8-9 MECHANICAL, PLUMBING AND ELECTRICAL REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . . 19

    Section

    8-901 Purpose, Intent and Scope . . . . . . . . . . . . . . . . . . . . . . 19 8-902 Mechanical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

    8-903 Plumbing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 8-904 Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

    CHAPTER 8-10 QUALIFIED HISTORICAL DISTRICTS,

    SITES AND OPEN SPACES . . . . . . . . . . . . . . . 23

    Section

  • CHBC § 8-6 High relevance — show source text

    CHAPTER 8-6 ACCESSIBILITY . . . . . . . . . . . . . . . . . . . . . . . . 11

    Section

    8-601 Purpose, Intent and Scope . . . . . . . . . . . . . . . . . . . . . . 11

    8-602 Basic Provisions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

    8-603 Alternatives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

    8-604 Equivalent Facilitation. . . . . . . . . . . . . . . . . . . . . . . . . . 12

    CHAPTER 8-7 STRUCTURAL REGULATIONS. . . . . . . . . . . . . 13

    Section

    8-701 Purpose, Intent and Scope . . . . . . . . . . . . . . . . . . . . . . 13 8-702 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

    8-703 Structural Survey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 8-704 Nonhistorical Additions and

    Nonhistorical Alterations . . . . . . . . . . . . . . . . . . . . . . . 13

    8-705 Structural Regulations . . . . . . . . . . . . . . . . . . . . . . . . . . 13 8-706 Lateral Load Regulations. . . . . . . . . . . . . . . . . . . . . . . . 14

    CHAPTER 8-8 ARCHAIC MATERIALS AND METHODS OF

    CONSTRUCTION . . . . . . . . . . . . . . . . . . . . . . . 15

    Section

    8-801 Purpose, Intent and Scope . . . . . . . . . . . . . . . . . . . . . . 15 8-802 General Engineering Approaches. . . . . . . . . . . . . . . . . 15 8-803 Nonstructural Archaic Materials. . . . . . . . . . . . . . . . . . 15

    8-804 Allowable Conditions for Specific Materials . . . . . . . 15 8-805 Masonry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 8-806 Adobe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

    8-807 Wood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

    8-808 Concrete . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Frequently asked questions

Can an enforcing agency require modern materials instead of historic ones?

No — for a qualified historical property the CHBC requires the enforcing agency to accept reasonably equivalent alternatives rather than mandating modern materials when such alternatives meet safety objectives. § 8-801.1

Does § 8-801.3 let me install modern materials that only look historic?

§ 8-801.3 expressly allows archaic materials to remain or be reinstalled and allows new materials “of the same class to match existing conditions.” Where a visual match is required, agencies will consider whether the replacement is the same class and whether the alternative is reasonably equivalent. § 8-801.3

Are safety and testing ignored under these rules?

No. The purpose/intent/scope sections are policy; technical testing and engineering evaluation (when needed) are handled in related CHBC sections (e.g., 8-802) and by the enforcing agency’s review. § 8-801.1–.3

If a historic material creates a clear life-safety hazard, can it stay?

The CHBC framework permits historic materials to remain only provided a life-safety hazard is not created or is mitigated. Agencies retain authority to require mitigation or alternates if hazards exist. § 8-801.1, § 8-801.3

Where do I find the technical limits for archaic materials (strength, testing)?

Technical limits and testing programs are in the material-specific and engineering sections of Chapter 8-8 (for example § 8-802 and the allowable-conditions subsections). The purpose/intent/scope sections do not list those technical numbers. § 8-801.1–.3, § 8-802

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