CHBC · California Historical Building Code

When does the CHBC Fire Protection chapter apply to a qualified historical building?

The Fire Protection chapter of the CHBC applies to a qualified historical building only when the CHBC as a whole applies to the proposed work under Section §8‑102 (for permitting, owner-elected CHBC use, state/local enforcement, repairs/alterations/additions, or unsafe-building remediation). Check §8‑401.1 (purpose) and §8‑401.3 (scope) and review §8‑102 subsections for the specific trigger; new construction, nonhistorical additions, and chapter‑specific exclusions may be handled under the regular code.

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Last reviewed: July 6, 2026

What the code requires — plain English

The CHBC Fire Protection chapter exists to give fire-protection rules tailored for qualified historical buildings and to allow reasonably equivalent alternatives to the regular code where appropriate — this is the purpose set out in § 8-401.1. The chapter’s scope is not automatic: the Fire Protection chapter “shall apply when required by the provisions of Section 8-102” — in other words, the Fire Protection rules apply to a historic building only when application of the CHBC is required under the CHBC’s general application rules in § 8-102 (see § 8-401.3).

The single most important rule: The CHBC Fire Protection chapter applies to a qualified historical building only when the CHBC is the appropriate code for the work or situation under Section § 8‑102 (see § 8‑401.3).

Requirements in detail

Core rule and where it comes from

  • Purpose: CHBC Fire Protection chapter exists to provide fire protection regulations and allow reasonably equivalent alternatives for qualified historical buildings; see § 8-401.1.
  • Scope trigger: The chapter “shall apply when required by the provisions of Section § 8‑102” (that is, when the CHBC generally applies to the work or building) — see § 8-401.3.

How to decide whether the Fire Protection chapter applies

The decision about whether Chapter 8‑4 applies is driven by the CHBC application rules in § 8‑102 (permitting, owner election, state/local agency jurisdiction, type of work, unsafe building remediation, etc.). Key application points from § 8‑102 include that the CHBC is used:

  • For permitting repairs, alterations, and additions necessary for preservation when the owner elects CHBC use or when the enforcing agency applies it; and
  • By state or local enforcing agencies when a permit/approval is requested for a qualified historical property. See § 8-102.1 and related subsections.

Decision table (quick reference)

Decision-relevant dimension Decision / threshold Code Reference
Applies at all? No — applies only when CHBC is required under § 8‑102 § 8-401.3
Why Chapter exists Provide fire protection rules and permit reasonably equivalent alternatives § 8-401.1
Typical triggers (examples) Permit for repairs, alterations, additions for preservation; owner election or enforcing agency application § 8-102.1
New construction / replicas Certain CHBC chapters explicitly exclude new construction/replicas (see accessibility example) — check chapter text § 8-601.3 (accessibility chapter example)
Work beyond the scope of the permit CHBC generally does not require additional work beyond the work undertaken (with some mandated exceptions) § 8-102.1.6
Owner/state agency action State or local enforcing agency shall apply CHBC for permitting when elected by owner or where agency has jurisdiction § 8-102.1

(Each table line is grounded in the CHBC application/scope language cited above.)

Exceptions & special cases

  • The Fire Protection chapter does not automatically apply to every historic property. It applies only where the CHBC is the applicable code per § 8‑102 (per § 8‑401.3). Do not assume automatic applicability for every change or work.
  • New construction and replicas: some CHBC chapters explicitly exclude new construction or reconstruction/replicas (for example, § 8‑601.3 in the Accessibility chapter). That means you must confirm chapter-by-chapter whether an exemption exists for new construction. If the CHBC chapter for a particular subject excludes new construction, the regular code will apply.
  • Nonhistorical additions: Where a proposed work is a nonhistorical addition, that new work must generally meet the regular code (see § 8‑102.1.1), even if the historic portion uses CHBC solutions.
  • Unsafe buildings: When correcting an unsafe qualified historical building, the CHBC applies to the corrective work and does not require bringing the whole building into regular-code compliance — see § 8‑102.1.5.

Common mistakes

  • Treating § 8‑401 (Fire Protection) as always applicable — the chapter only applies when CHBC is the applicable code under § 8‑102 (misses the scope trigger in § 8‑401.3).
  • Assuming new construction of a “historic-style” building automatically gets CHBC relief; several CHBC chapters explicitly exclude new construction/replicas (check § 8‑601.3 for the accessibility example) and nonhistorical new construction must follow the regular code.
  • Requiring more work than the permit scope: applying the regular code beyond the specific work being undertaken — CHBC limits “additional work” required by the regular code in many situations (see § 8‑102.1.6).

Worked example — concrete scenario

Scenario: A private owner plans interior alterations to a qualified historical one‑story commercial building (historical form retained). The owner files for a permit to alter 12,000 sq ft of floor area.

  1. Is the Fire Protection chapter applicable?

    • Start with § 8‑401.3: the chapter applies when required by § 8‑102. Since the owner is requesting a permit for alterations to a qualified historical building and the owner is electing CHBC application (or the enforcing agency applies the CHBC for permitting), the CHBC applies to the permit review — therefore the Fire Protection chapter is potentially applicable. Cite: § 8‑401.3 and § 8‑102.1.

  2. Do special floor-area rules change the outcome?

    • The CHBC allows a one‑story historic building to have up to 15,000 square feet unless other rules of regular code apply; because this building is 12,000 sq ft (< 15,000 sq ft), it falls below that CHBC threshold (see § 8‑302.4). If the owner wanted to increase area above 15,000 square feet, other CHBC provisions (or installation of an automatic sprinkler system) would be relevant.

  3. Result: The Fire Protection chapter applies to the permit review because the work is an alteration on a qualified historical building and the CHBC is being applied per § 8‑102; specific fire-protection measures will be evaluated under Chapter 8‑4 (Fire Protection) and any accepted alternatives allowed by CHBC § 8‑401.1. If the owner instead proposed a nonhistorical addition that expands the building beyond historic footprint, the new work may need to comply with the regular code for that new construction.

Related provisions (CHBC sections to check)

  • § 8‑401.1 — Purpose of the Fire Protection chapter.
  • § 8‑401.3 — Scope: chapter applies when required by § 8‑102.
  • § 8‑102.1 — Application rules for CHBC (owner election, permitting, state/local enforcing agency duties).
  • § 8‑102.1.1 — Additions, alterations and repairs; nonhistorical additions must conform to regular code.
  • § 8‑102.1.5 — Unsafe buildings: CHBC applies to corrective work for unsafe conditions.
  • § 8‑302.4 — Maximum floor area rules (15,000 sq ft one‑story threshold referenced above).
  • § 8‑601.3 — Example chapter-level exclusion for new construction/replicas (accessibility chapter). Verify chapter text for similar exclusions.

Code references

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

  • 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:

    1. An automatic sprinkler system throughout. See Section 8-410 for automatic sprinkler systems.
    2. An approved life safety evaluation.
    3. 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 § 8-6 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 § 8-9 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 § 8-503 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 § 8-302.6 High relevance — show source text

    8-302.6 Fire-resistive construction. See Chapter 8-4.

    8-302.7 Light and ventilation. Existing provisions for light and ventilation which do not, in the opinion of the enforcing agency, constitute a safety hazard may remain. See Section 8-303.6 for residential requirements. See Section 8-503 for Escape or Rescue Windows and Doors.

    SECTION 8-303 — RESIDENTIAL OCCUPANCIES

    8-303.1 Purpose. The purpose of this section is to provide regulations for those buildings designated as qualified historical buildings or properties and classified as residential occupancies. The CHBC requires enforcing agencies to accept any reasonably equivalent alternative to the regular code when dealing with qualified historical buildings and properties.

    8-303.2 Intent. The intent of the CHBC is to preserve the integrity of qualified historical buildings and properties while maintaining a reasonable degree of protection of life, health and safety for the occupants.

    8-303.3 Application and scope. The provisions of this section shall apply to all qualified historical buildings used for human habitation. Those dwelling units intended only for display, or public use with no residential use involved, need not comply with the requirements of this section.

    8-303.4 Fire escapes. See Chapter 8-5.

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    USE AND OCCUPANCY

    8-303.5 Room dimensions. Rooms used for sleeping purposes may contain a minimum of 50 square feet (4.6 m [2] ) floor area, provided there is maintained an average ceiling height of 7 feet (2134 mm). Other habitable rooms need only be of adequate size to be functional for the purpose intended.

    8-303.6 Light and ventilation. Windows in habitable rooms shall have an area of 6 percent of the floor area, or 6 square feet (0.56 m [2] ), whichever is greater. Windows in sleeping rooms shall be openable (see Section 8-503). Residential occupancies need not be provided with electrical lighting.

    8-303.7 Alteration and repair. The alteration and repair of qualified historical buildings or properties may permit the replacement, retention and extension of original materials and the continued use of original methods of construction, provided a life safety hazard is not created or continued. Alterations and repairs shall be consistent with the CHBC.

    The amount of alterations and repairs is not limited, provided there is no nonhistorical increase in floor area, volume or size of the building or property.

    8-303.8 Exiting. See Chapter 8-5.

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    8-4 FIRE PROTECTION

    SECTION 8-401 — PURPOSE, INTENT AND SCOPE

    8-401.1 Purpose. The purpose of this chapter is to provide regulations for fire protection of qualified historical buildings or properties. The CHBC requires enforcing agencies to accept any reasonably equivalent alternatives to the regular code when dealing with qualified historical buildings or properties.

    8-401.2 Intent. The intent of the CHBC is to preserve the integrity of qualified historical buildings or properties while maintaining a reasonable degree of fire protection based primarily on the life safety of the occupants and firefighting personnel.

  • CHBC § 3307.2 High relevance — show source text

    Exception: Approved temporary means of egress and accessible means of egress systems and facilities.

    3307.2 Water supply for fire protection. An approved water supply for fire protection, either temporary or permanent, shall be made available as soon as combustible building materials arrive on the site, on commencement of vertical combustible construction and on installation of a standpipe system in buildings under construction, in accordance with Sections 3307.2.1 through 3307.4.

    Exception: The fire code official is authorized to reduce the fire-flow requirements for isolated buildings or a group of buildings in rural areas or small communities where the development of full fire-flow requirements is impractical.

    3307.2.1 Combustible building materials. When combustible building materials of the building under construction are delivered to a site, a minimum fire flow of 500 gallons per minute (1893 L/m) shall be provided. The fire hydrant used to provide this fire-flow supply shall be within 500 feet (152 m) of the combustible building materials, as measured along an approved fire apparatus access lane. Where the site configuration is such that one fire hydrant cannot be located within 500 feet (152 m) of all combustible building materials, additional fire hydrants shall be required to provide coverage in accordance with this section.

    3307.2.2 Vertical construction of Types III, IV and V construction. Prior to commencement of vertical construction of Type III, IV or V buildings that utilize any combustible building materials, the fire flow required by Sections 3307.2.2.1 through 3307.2.2.3 shall be provided, accompanied by fire hydrants in sufficient quantity to deliver the required fire flow and proper coverage.

    3307.2.2.1 Fire separation up to 30 feet. Where a building of Type III, IV or V construction has a fire separation distance of less than 30 feet (9144 mm) from property lot lines, and an adjacent property has an existing structure or otherwise can be built on, the water supply shall provide either a minimum of 500 gallons per minute (1893 L/m) or the entire fire flow required for the building when constructed, whichever is greater.

    3307.2.2.2 Fire separation of 30 feet up to 60 feet. Where a building of Type III, IV or V construction has a fire separation distance of 30 feet (9144 mm) up to 60 feet (18 288 mm) from property lot lines, and an adjacent property has an existing structure or otherwise can be built on, the water supply shall provide a minimum of 500 gallons per minute (1893 L/m) or 50 percent of the fire flow required for the building when constructed, whichever is greater.

    3307.2.2.3 Fire separation of 60 feet or greater. Where a building of Type III, IV or V construction has a fire separation of 60 feet (18 288 mm) or greater from a property lot line, a water supply of 500 gallons per minute (1893 L/m) shall be provided.

    3307.3 Vertical construction, Type I and II construction. If combustible building materials are delivered to the construction site, water supply in accordance with Section 3307.2.1 shall be provided. Additional water supply for fire flow is not required prior to commencing vertical construction of Type I and II buildings.

    3307.4 Standpipe supply. Regardless of the presence of combustible building materials, the construction type or the fire separation distance, where a standpipe is required in accordance with Section 3307.5, a water supply providing a minimum flow of 500 gallons

  • CHBC § 8-1002.1 Medium relevance — show source text

    8-1002.1 The CHBC shall apply to all sites and districts and their features associated with qualified historical buildings or qualified historical districts as outlined in 8-1001.2 Scope.

    8-1002.2 Where the application of regular code may impact the associated features of qualified historical properties beyond their footprints, by work performed secondarily, those impacts shall also be covered by the CHBC.

    8-1002.3 This chapter shall be applied for all issues regarding code compliance or other standard or regulation as they affect the purpose of this chapter.

    8-1002.4 The application of any code or building standard shall not unduly restrict the use of a qualified historical building or property that is otherwise permitted pursuant to Chapter 8-3 and the intent of the State Historical Building Code, Section 18956.

    SECTION 8-1003 — SITE RELATIONS

    The relationship between a building or property and its site, or the associated features of a district (including qualified historical landscape), site, objects and their features are critical components that may be one of the criteria for these buildings and properties to be qualified under the CHBC. The CHBC recognizes the importance of these relationships. This chapter shall be used to provide context sensitive solutions for treatment of qualified historical buildings, properties, district or their associated historical features, or when work to be performed secondarily impacts the associated historical features of a qualified historical building or property.

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    APPENDIX A Col2 Col3 Col4
    CHAPTER 8-6—TABLE 1—PROVISION APPLICABILITY CHAPTER 8-6—TABLE 1—PROVISION APPLICABILITY CHAPTER 8-6—TABLE 1—PROVISION APPLICABILITY CHAPTER 8-6—TABLE 1—PROVISION APPLICABILITY
    Title II
    Public 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 § 0.34 Medium relevance — show source text

    32 to 0.34|250|4.5|5.0|5.0|5.0|5.0| |251 to 350|0.29 to 0.32|200|3.0|4.0|4.5|4.5|4.5| |201 to 250|0.27 to 0.30|150|2.5|2.5|2.5|3.0|3.0| |141 to 200|0.25 to 0.29|125|1.5|1.5|2.0|2.0|2.0| |105 to 140|0.22 to 0.28|100|1.0|1.0|1.5|1.5|1.5|

    For SI units: °C=(°F-32)/1.8, 1 inch = 25 mm, 1 British thermal unit inch per hour square foot degree Fahrenheit = [0.1 W/(m•K)]

    Notes: 1 For insulation outside the stated conductivity range, the minimum thickness ( T ) shall be determined as follows: T = r {(1 + t / r ) [K] [/] [k ] – 1}

    Where:

    T = minimum insulation thickness (inches). r = actual outside radius of pipe (inches). t = insulation thickness listed in this table for applicable fluid temperature and pipe size. K = conductivity of alternate material at mean rating temperature indicated for the applicable fluid temperature [Btu•in/(h•ft [2] - °F)] [W/(m•K)]. k = the upper value of the conductivity range listed in this table for the applicable fluid temperature. 2 These thicknesses are on energy efficiency considerations only. Additional insulation is sometimes required relative to safety issues/surface temperature. 3 For piping smaller than 1 1 ⁄ 2 inches (40 mm) or less and located in partitions within conditioned spaces, reduction of these thicknesses by 1 inch (25.4 mm) shall be permitted (before thickness adjustment required in footnote 1) but not to thicknesses below 1 inch (25.4 mm). 4 For direct-buried heating and hot water system piping, reduction of these thicknesses by 1 1 ⁄ 2 inch (40 mm) shall be permitted (before thickness adjustment required in footnote 1) but not to thicknesses below 1 inch (25.4 mm). 5 Table E 503.7.3(1) is based on steel pipe. Nonmetallic pipes schedule 80 thickness or less shall use the table values. For other nonmetallic pipes having thermal resistance more than that of steel pipe, reduced insulation thicknesses are permitted where documentation is provided showing that the pipe with the proposed insulation has no more heat transfer per foot (mm) than a steel pipe of the same size with the insulation thickness shown in Table E 503.7.3(1).

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    ), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

    APPENDIX E

    TABLE E 503.7.3(2) MINIMUM PIPE INSULATION THICKNESS FOR COOLING SYSTEMS (CHILLED WATER, BRINE, AND REFRIGERANT) [1,2,3,4 ]

    [ASHRAE 90.1: TABLE 6.8.3-2]

  • CHBC § 25.4 Medium relevance — show source text

    This table applies only to wood joist construction. It is not applicable to wood truss construction.|For SI: 1 inch = 25.4 mm.
    a. This table applies only to wood joist construction. It is not applicable to wood truss construction.|For SI: 1 inch = 25.4 mm.
    a. This table applies only to wood joist construction. It is not applicable to wood truss construction.|

    TABLE 722.6.2(5)—TIME ASSIGNED FOR ADDITIONAL PROTECTION Col2
    DESCRIPTION OF ADDITIONAL PROTECTION FIRE RESISTANCE
    (minutes)
    Add to the fire-resistance rating of wood stud walls if the spaces between the studs are completely filled with glass
    fiber mineral wool batts weighing not less than 2 pounds per cubic foot (0.6 pound per square foot of wall surface),
    or cellulose insulation having a nominal density not less than 2.6 pounds per cubic foot.    		 15
    For SI: 1 pound/cubic foot = 16.0185 kg/m3. For SI: 1 pound/cubic foot = 16.0185 kg/m3.

    722.6.2.1 Fire-resistance rating of wood frame assemblies. The fire-resistance rating of a wood frame assembly is equal to the sum of the time assigned to the membrane on the fire-exposed side, the time assigned to the framing members and the time assigned for additional contribution by other protective measures such as insulation. The membrane on the unexposed side shall not be included in determining the fire resistance of the assembly.

    722.6.2.2 Time assigned to membranes. Table 722.6.2(1) indicates the time assigned to membranes on the fire-exposed side.

    722.6.2.3 Exterior walls. For an exterior wall with a fire separation distance greater than 10 feet (3048 mm), the wall is assigned a rating dependent on the interior membrane and the framing as described in Table 722.6.2(1) and Table 722.6.2(2). The membrane on the outside of the nonfire-exposed side of exterior walls with a fire separation distance greater than 10 feet (3048 mm) shall consist of sheathing, sheathing paper and siding as described in Table 722.6.2(3).

    722.6.2.4 Floors and roofs. In the case of a floor or roof, the standard test provides only for testing for fire exposure from below. Except as noted in Section 703.2.3, floor or roof assemblies of wood framing shall have an upper membrane consisting of a subfloor and finished floor conforming to Table 722.6.2(4) or any other membrane that has a contribution to fire resistance of not less than 15 minutes in Table 722.6.2(1).

    722.6.2.5 Additional protection. Table 722.6.2(5) indicates the time increments to be added to the fire resistance where glass fiber, rockwool, slag mineral wool or cellulose insulation is incorporated in the assembly.

    722.6.2.6 Fastening. Fastening of wood frame assemblies and the fastening of membranes to the wood framing members shall be done in accordance with Chapter 23.

    722.7 Fire-resistance rating for mass timber. The required fire resistance of mass timber elements in Section 602.4 shall be determined in accordance with Section 703.2 or Section 703.3 . The fire-resistance rating of building elements shall be as required in Tables

  • CHBC § 8-102.1.1 Medium relevance — show source text
    1. State agencies. All state agencies shall apply the provisions of the CHBC in permitting repairs, alterations and additions necessary for the preservation, restoration, rehabilitation, safety, relocation, reconstruction or continued use of qualified historical buildings or properties.

    8-102.1.1 Additions, alterations and repairs. It is the intent of the CHBC to allow nonhistorical expansion or addition to a qualified historical building or property, provided nonhistorical additions shall conform to the requirements of the regular code (as defined in Chapter 8-2).

    8-102.1.2 Relocation. Relocated qualified historical buildings or properties shall be sited to comply with the regular code or with the solutions listed in the CHBC. Nonhistorical new construction related to relocation shall comply with the regular code. Reconstruction and restoration related to relocation is permitted to comply with the provisions in the CHBC.

    8-102.1.3 Change of occupancy. For change of use or occupancy, see Chapter 8-3, Use and Occupancy.

    8-102.1.4 Continued use. Qualified historical buildings or properties may have their existing use or occupancy continued if such use or occupancy conformed to the code or to the standards of construction in effect at the time of construction, and such use or occupancy does not constitute a distinct hazard to life safety as defined in the CHBC.

    8-102.1.5 Unsafe buildings or properties. When a qualified historical building or property is determined to be unsafe as defined in the regular code, the requirements of the CHBC are applicable to the work necessary to correct the unsafe conditions. Work to remediate the buildings or properties need only address the correction of the unsafe conditions, and it shall not be required to bring the entire qualified historical building or property into compliance with regular code.

    8-102.1.6 Additional work. Qualified historical buildings or properties shall not be subject to additional work required by the regular code, regulation or ordinance beyond that required to complete the work undertaken. Certain exceptions for accessibility and for distinct hazards exist by mandate and may require specific action, within the parameters of the CHBC.

    SECTION 8-103 — ORGANIZATION AND ENFORCEMENT

    8-103.1 Authority. The state or local enforcing agency, pursuant to authority provided under Section 18954 of the Health and Safety Code, shall administer and enforce the provisions of the CHBC in permitting repairs, alterations and additions necessary for the preservation, restoration, reconstruction, rehabilitation, relocation or continued use of a qualified historical building or property.

    8-103.2 State enforcement. All state agencies pursuant to authority provided under Section 18954 and Section 18961 of the Health and Safety Code shall administer and enforce the CHBC with respect to qualified historical buildings or properties under their respective jurisdiction.

    8-103.3 Liability. Prevailing law regarding immunity of building officials is unaffected by the use and enforcement of the CHBC.

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    ADMINISTRATION

    SECTION 8-104 — REVIEW AND APPEALS

    8-104.1 State Historical Building Safety Board (SHBSB or Board). In order to provide for interpretation of the provisions of the CHBC and to hear appeals, the SHBSB shall act as an appeal and review body to state and local agencies or any affected party.

    **8-104.2 SHBSB review.

  • CHBC § 8-1001 Medium relevance — show source text

    Section

    8-1001 Purpose and Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 8-1002 Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 8-1003 Site Relations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

    APPENDIX A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

    HISTORY NOTE APPENDIX . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

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    8-1 ADMINISTRATION

    Note: The California Historical Building Code, Part 8 of Title 24, governs for all qualified historical buildings or properties in the State of California.

    SECTION 8-101 — TITLE, PURPOSE AND INTENT

    8-101.1 Title. These regulations shall be known as the California Historical Building Code and will be referred to herein as “the CHBC.”

    8-101.2 Purpose. The purpose of the CHBC is to provide regulations for the preservation, restoration, rehabilitation, relocation or reconstruction of buildings or properties designated as qualified historical buildings or properties (as defined in Chapter 8-2). The CHBC is intended to provide solutions for the preservation of qualified historical buildings or properties, to promote sustainability, to provide access for persons with disabilities, to provide a cost-effective approach to preservation, and to provide for the reasonable safety of the occupants or users. The CHBC requires enforcing agencies to accept solutions that are reasonably equivalent to the regular code (as defined in Chapter 8-2) when dealing with qualified historical buildings or properties.

    8-101.3 Intent. The intent of the CHBC is to facilitate the preservation and continuing use of qualified historical buildings or properties while providing reasonable safety for the building occupants and access for persons with disabilities.

    SECTION 8-102 — APPLICATION

    8-102.1 Application. The CHBC is applicable to all issues regarding code compliance for qualified historical buildings or properties. The CHBC may be used in conjunction with the regular code to provide solutions to facilitate the preservation of qualified historical buildings or properties. The CHBC shall be used by any agency with jurisdiction and whenever compliance with the code is required for qualified historical buildings or properties.

    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 § 8-3 Medium relevance — show source text

    TREATMENT. An act of work to carry out preservation, restoration, stabilization, rehabilitation or reconstruction.

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    8-3 USE AND OCCUPANCY

    SECTION 8-301 — PURPOSE AND SCOPE

    8-301.1 Purpose. The purpose of the CHBC is to provide regulations for the determination of occupancy classifications and conditions of use for qualified historical buildings or properties.

    8-301.2 Scope. Every qualified historical building or property for which a permit or approval has been requested shall be classified prior to permit issuance according to its use or the character of its occupancy in accordance with the regular code and applicable provisions of this chapter.

    SECTION 8-302 — GENERAL

    8-302.1 Existing use. The use or character of occupancy of a qualified historical building or property, or portion thereof, shall be permitted to continue in use regardless of any period of time in which it may have remained unoccupied or in other uses, provided such building or property otherwise conforms to all applicable requirements of the CHBC.

    8-302.2 Change in occupancy. The use or character of the occupancy of a qualified historical building or property may be changed from or returned to its historical use or character, provided the qualified historical building or property conforms to the requirements applicable to the new use or character of occupancy as set forth in the CHBC. Such change in occupancy shall not mandate conformance with new construction requirements as set forth in regular code.

    8-302.3 Occupancy separations. Required occupancy separations of more than one hour may be reduced to one-hour fire-resistive construction with all openings protected by not less than three-fourths-hour fire-resistive assemblies of the self-closing or automatic-closing type when the building is provided with an automatic sprinkler system throughout the entire building in accordance with Section 8-410.2. Doors equipped with automatic-closing devices shall be of a type which will function upon activation of a device which responds to products of combustion other than heat.

    Required occupancy separations of one hour may be omitted when the building is provided with an automatic sprinkler system throughout.

    8-302.4 Maximum floor area. Regardless of the use or character of occupancy, the area of a one-story qualified historical building or property may have, but shall not exceed, a floor area of 15,000 square feet (1393.5 m [2] ) unless such an increase is otherwise permitted in regular code. Multistory qualified historical buildings (including basements and cellars) shall be in accordance with regular code requirements.

    Exception: Historical buildings may be unlimited in floor area without fire-resistive area separation walls:

    1. When provided with an automatic sprinkler, or
    2. Residential occupancies of two stories or less when provided with a complete fire alarm and annunciation system and where the exiting system conforms to regular code.

    8-302.5 Maximum height. The maximum height and number of stories of a qualified historical building or property shall not be limited because of construction type, provided such height or number of stories does not exceed that of its historical design.

Frequently asked questions

When exactly does § 8‑401.3 make the Fire Protection chapter apply?

It makes Chapter 8‑4 applicable when the CHBC itself applies to the work or building under § 8‑102 — i.e., the Fire Protection rules apply only in cases where the CHBC is the correct code for the proposed permitting, repair, alteration, addition, relocation, or corrective work.

Does the Fire Protection chapter cover new construction that looks historic?

Not automatically. Some CHBC chapters explicitly exclude new construction or replicas (see § 8‑601.3 for accessibility); also nonhistorical new construction typically must meet the regular code per § 8‑102.1.1. Check the applicable CHBC chapter language for the project.

If the owner doesn’t invoke CHBC, can the enforcing agency still apply it?

Yes. The state or local enforcing agency shall apply the CHBC when it is the correct code for permitting repairs, alterations and additions to a qualified historical building; see § 8‑102.1.

Does an unsafe historical building have to be fully brought to regular-code standards?

No. When a qualified historical building is deemed unsafe, CHBC applies to the corrective work and does not require bringing the entire building into compliance with the regular code beyond what’s necessary to correct the unsafe condition (see § 8‑102.1.5).

If I install sprinklers, does that change Fire Protection chapter applicability?

Installing sprinklers can affect which fire-resistive requirements are required or may be reduced under CHBC provisions (see Chapter 8‑4 provisions on sprinkler alternatives), but the threshold question of whether Chapter 8‑4 applies remains whether CHBC applies under § 8‑102 and § 8‑401.3.

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