CHBC · California Historical Building Code

Are additions, relocations, or change of occupancy covered by the CHBC?

If your property is a designated historic building, the CHBC lets you add on, move it, or change its use while protecting historic fabric — but any new, nonhistoric portion (or new construction tied to a move) usually must meet the regular building code; change of use follows Chapter 8‑3 and does not automatically force full new‑construction rules.

Last reviewed: July 6, 2026

What the code requires

The California Historical Building Code (CHBC) applies to permitted work on a qualified historical building or property and specifically addresses additions, relocation, and change of occupancy. In plain English: the CHBC allows nonhistorical additions so long as those additions meet the regular code; it permits relocation when the relocated resource and any new nonhistorical construction meet either the regular code or CHBC solutions; and change of occupancy for historic resources is handled in Chapter 8‑3 (does not automatically force full new‑construction compliance). See § 8‑102.1.1, § 8‑102.1.2, and § 8‑102.1.3 for the controlling rules.

The single most important rule: CHBC is intended to allow preservation‑oriented work on qualified historic resources, but nonhistorical new work generally must meet the regular code unless CHBC provides an explicit alternative. § 8‑102.1.1 / § 8‑102.1.2 / § 8‑102.1.3.

Requirements in detail

Key defined terms (first use is bolded)

  • Qualified historical building or property — a building or property designated on a recognized historic register or inventory and thus eligible for CHBC treatments.
  • Regular code — the adopted nonhistoric building regulations that normally govern new construction (i.e., the “regular code” referenced throughout the CHBC).
  • Nonhistorical addition — new construction added to a historic building that is not itself a historic element.

Decision table — when and how the CHBC applies

Work type Allowed under CHBC? Decision‑relevant dimensions / required condition Code Reference
Addition / nonhistorical expansion Yes — permitted to be used with CHBC for historic preservation, but nonhistorical additions must meet regular code If the addition is nonhistorical, it must conform to the regular code; CHBC intent is to allow expansion while preserving the historic fabric. § 8‑102.1.1
Relocation of historic building/property Yes — relocation permitted with siting and reconstruction conditions The relocated resource must be sited to comply with the regular code or CHBC solutions; new nonhistorical construction related to the relocation must comply with the regular code; reconstruction/restoration may follow CHBC provisions. § 8‑102.1.2
Change of occupancy / use Yes — handled by Chapter 8‑3 The change of use is permitted provided the historic resource meets the requirements applicable to the new use as set out in Chapter 8‑3; a change does not automatically require full conformance with new‑construction regular code. § 8‑102.1.3 and § 8‑302.2

How the enforcing agency uses the CHBC

  • The local or state enforcing agency applies CHBC provisions for repairs, alterations, additions, relocation or continued use when elected by the owner (see the general application in Section 8‑102). § 8‑102.1.
  • State agencies must apply CHBC for qualifying projects under their jurisdiction. § 8‑102.1 (2).

Exceptions & special cases

  • Nonhistorical additions: although CHBC permits expansion, any nonhistorical addition must conform to the regular code — there is no CHBC waiver for the new portion itself. § 8‑102.1.1.
  • Relocation: the historic building moved to a new site must be sited to comply with the regular code or with CHBC solutions; any new nonhistoric construction that is part of the relocation must comply with the regular code. § 8‑102.1.2.
  • Change of occupancy: CHBC Chapter 8‑3 governs change‑of‑use provisions; the CHBC expressly states a change of occupancy need not mandate new‑construction compliance, but the building must meet the CHBC requirements applicable to the new use. § 8‑102.1.3; see § 8‑302.2.
  • Continued use: an existing historic use may be continued if it conformed to the code at time of construction and does not present a distinct life‑safety hazard. § 8‑102.1.4.

Common mistakes

  • Treating an addition to a historic building as fully eligible for CHBC relief: the CHBC allows retention of historic fabric but requires that nonhistorical additions comply with the regular code (mistaking “allowed” for “exempt”). § 8‑102.1.1.
  • Assuming relocation automatically removes CHBC protections: relocation can be permitted under CHBC, but siting and new construction must meet regular code or CHBC solutions — don’t assume a blanket exemption. § 8‑102.1.2.
  • Thinking a change of occupancy forces full new‑construction compliance: CHBC Chapter 8‑3 provides the path for change of use and explicitly notes such change “shall not mandate conformance with new construction requirements” in the regular code. § 8‑302.2.

Worked example

Scenario: A historic school (qualified historic building) will be moved 200 ft to a nearby lot and a 2,000 sq ft single‑story classroom addition (nonhistoric) will be attached after relocation.

Step 1 — Relocation: The relocation itself may be permitted under the CHBC, but the relocated building must be sited to comply with the regular code or with CHBC siting solutions. If the new site raises regular‑code requirements (setbacks, fire separation, foundation), address those using either regular code solutions or CHBC alternatives. § 8‑102.1.2.

Step 2 — New addition (2,000 sq ft): Because the addition is nonhistorical, it must conform to the regular code (structural, egress, fire and accessibility for new construction). The CHBC allows the historic resource to be treated under CHBC provisions, but the new portion is new construction under regular code. § 8‑102.1.1.

Step 3 — Restoration/reconstruction tied to relocation: Reconstruction or restoration related to relocation may comply with CHBC provisions rather than full regular‑code new‑construction requirements — use CHBC for historic restoration details where applicable. § 8‑102.1.2.

Net: The project can proceed under the CHBC for the historic resource and its restoration, but expect the 2,000 sq ft addition and any new foundations/site work to meet regular‑code requirements unless an approving authority accepts a CHBC‑based alternative for specific items. § 8‑102.1.1, § 8‑102.1.2.

Related provisions (CHBC sections)

  • § 8‑102.1 — Application of the CHBC (general authority for repairs, alterations, additions, relocation).
  • § 8‑102.1.1 — Additions, alterations and repairs (nonhistorical additions must conform to regular code).
  • § 8‑102.1.2 — Relocation (siting and new construction requirements).
  • § 8‑102.1.3 — Change of occupancy (see Chapter 8‑3).
  • § 8‑302.2 — Change in occupancy details for qualified historical buildings (change does not mandate new‑construction requirements).
  • § 8‑303.7 — Alteration and repair: retention/extension of original materials allowed where life‑safety hazards are not created.
  • § 8‑302.4 — Maximum floor area exceptions (useful for additions and area calculations).

Code references

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

  • CHBC § 8-101.1 High relevance — show source text

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

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

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

    SECTION 8-102 APPLICATION

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

    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 § 8-102.1.1 High 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 § 8-3 High relevance — show source text

    This shall include historical buildings or properties on, or determined eligible for, national, state or local historical registers or inventories, such as the National Register of Historic Places, California Register of Historical Resources, State Historical Landmarks, State Points of Historical Interest, and city or county registers, inventories or surveys of historical or architecturally significant sites, places or landmarks.

    RECONSTRUCTION. The act or process of depicting, by means of new construction, the form, features and detailing of a nonsurviving site, landscape, building, property or object for the purpose of replicating its appearance at a specific period of time.

    REGULAR CODE. The adopted regulations that govern the design and construction or alteration of nonhistorical buildings and properties within the jurisdiction of the enforcing agency.

    REHABILITATION. The act or process of making possible a compatible use for qualified historical building or property through repair, alterations and additions while preserving those portions or features which convey its qualified historical, cultural or architectural values.

    RELOCATION. The act or process of moving any qualified historical building or property or a portion of a qualified historical building or property to a new site, or a different location on the same site.

    REPAIR. Renewal, reconstruction or renovation of any portion of an existing property, site or building for the purpose of its continued use.

    RESTORATION. The act or process of accurately depicting the form, features and character of a qualified building or property as it appeared at a particular period of time by the means of the removal of features from other periods in its history and reconstruction of missing features from the restoration period. The limited and sensitive upgrading of mechanical, electrical and plumbing systems and other code-required work to make properties functional is appropriate within a restoration project.

    STRUCTURE. That which is built or constructed, an edifice or a building of any kind, or any piece of work artificially built up or composed of parts joined together in some definite manner.

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

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    8-3 USE AND OCCUPANCY

    SECTION 8-301 PURPOSE AND SCOPE

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

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

    SECTION 8-302 GENERAL

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

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

  • CHBC § 101.1 High relevance — show source text

    This code is intended to be adopted as a legally enforceable document, and it cannot be effective without adequate provisions for its administration and enforcement. The provisions of Chapter 1 establish the authority and duties of the code official appointed by the authority having jurisdiction and also establish the rights and privileges of the registered design professional, contractor and property owner.

    Section 104 was revised for the 2024 edition of the IEBC. For complete information, see the Relocations table in the Preface of this code.

    PART 1—SCOPE AND APPLICATION

    SECTION 101—SCOPE AND GENERAL REQUIREMENTS

    [A] 101.1 Title. These regulations shall be known as the Existing Building Code of [ NAME OF JURISDICTION ], herein-after referred to as “this code.”

    [A] 101.2 Scope. The provisions of this code shall apply to the repair, alteration, change of occupancy, addition to and relocation of existing buildings.

    Exception: Detached one- and two-family dwellings and townhouses not more than three stories above grade plane in height with a separate means of egress, and their accessory structures not more than three stories above grade plane in height, shall comply with this code or the California Residential Code.

    [A] 101.2.1 Appendices. Provisions in the appendices shall not apply unless specifically adopted or referenced.

    101.2.2 Application of fire code. Where work regulated by this code is also regulated by the construction requirements for existing buildings in Chapter 11 of the California Fire Code, such work shall comply with applicable requirements in both codes.

    [A] 101.3 Purpose. The intent of this code is to provide flexibility to permit the use of alternative approaches to achieve compliance with minimum requirements to provide a reasonable level of safety, health, property protection and general welfare insofar as they are affected by the repair, alteration, change of occupancy, addition and relocation of existing buildings.

    [A] 101.4 Applicability. This code shall apply to the repair, alteration, change of occupancy, addition and relocation of existing buildings, regardless of occupancy, subject to the criteria of Sections 101.4.1 and 101.4.2.

    [A] 101.4.1 Buildings not previously occupied. A building or portion of a building that has not been previously occupied or used for its intended purpose, in accordance with the laws in existence at the time of its completion, shall be permitted to comply with the provisions of the laws in existence at the time of its original permit unless such permit has expired. Subsequent permits shall comply with the California Building Code or California Residential Code, as applicable, for new construction.

    [A] 101.4.2 Buildings previously occupied. The legal occupancy of any building existing on the date of adoption of this code shall be permitted to continue without change, except as is specifically covered in this code, the California Fire Code, or the Inter- national Property Maintenance Code, or as is deemed necessary by the code official for the general safety and welfare of the occupants and the public.

    [A] 101.5 Safeguards during construction. Construction work covered in this code, including any related demolition, shall comply with the requirements of Chapter 15.

  • CHBC § 323-9843 High relevance — show source text

    State Librarian [SL]

    library.ca.gov csllaw@library.ca.gov (916) 323-9843 Public Library Construction & Renovation

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    HOW TO DETERMINE WHERE CHANGES HAVE BEEN MADE

    Symbols in the margins indicate where changes have been made or language has been deleted.

    This symbol indicates that a change has been made.

    • This symbol indicates deletion of language.

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    PART 8 CONTAINS ALTERNATIVE REGULATIONS

    FOR QUALIFIED HISTORICAL BUILDINGS

    The California Historical Building Code (CHBC) is unique among state regulations. The authoring of the original CHBC required state agencies promulgating regulations for building construction to work in harmony with representatives of other design and construction disciplines. The result was a totally new approach to building codes for historical structures, which maintains currently acceptable life safety standards. These regulations are also unique in that they are performance oriented rather than prescriptive. The provisions of the CHBC are to be applied by the enforcing authority of every city, county, city and county, or state agency in permitting repairs, alterations and additions necessary for the preservation, rehabilitation, relocation, related construction, change of use or continued use of a qualified historical building. The authority for use of the CHBC is vested in Sections 18950 through 18961 of the Health and Safety Code. Section 18954 states, “The building department of every city or county or other local agency that has jurisdiction over the enforcement of code within its legal authority shall apply the alternative standards and regulations adopted pursuant to Section 18959.5 in permitting repairs, alterations, and additions necessary for the preservation, restoration, rehabilitation, safety, moving, or continued use of a qualified historical building or structure. A state agency shall apply the alternative regulations adopted pursuant to Section 18959.5 in permitting repairs, alterations, and additions necessary for the preservation, restoration, rehabilitation, safety, moving, or continued use of a qualified historical building or structure.” However, be aware that in order to use the CHBC, the structure under consideration must be qualified by being designated as an historical building or structure. Section 18955 states, “For the purposes of this part, a qualified historical building or structure is any structure or property, collection of structures, and their related sites deemed of importance to the history, architecture, or culture of an area by an appropriate local or state governmental jurisdiction. This shall include historical buildings or structures on existing or future national, state or local historical registers or official inventories, such as the National Register of Historic Places, State Historical Landmarks, State Points of Historical Interest, and city or county registers or inventories of historical or architecturally significant sites, places, historic districts, or landmarks. This shall also include places, locations, or sites identified on these historical registers or official inventories and deemed of importance to the history, architecture, or culture of an area by an appropriate local or state governmental jurisdiction.” The regulations of the CHBC have the same authority as state law and are to be considered as such. Liability is the same as for prevailing law. The intent of the CHBC is to save California’s architectural heritage by recognizing the unique construction problems inherent in historical buildings and by providing a code to deal with these problems.

  • CHBC § 1.10.1 High relevance — show source text

    Chapter 5A Prescriptive Compliance Method.

    Chapter 5A provides details for the prescriptive compliance method for alteration, addition and change of occupancy of existing build- ings and structures regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development, which include hospitals and correctional treatment centers (applications listed in Sections 1.10.1 (OSHPD 1).

    Chapter 6 Classification of Work.

    Chapter 6 provides an overview of the Work Area Method and defines the different classifications of work including alterations, change of occupancy, additions and historic buildings. Detailed requirements for all of these are given in subsequent Chapters 7 through 11.

    Chapter 7 Alterations—Level 1.

    Chapter 7 provides the technical requirements for those existing buildings that undergo Level 1 alterations as described in Section 602, which includes replacement or covering of existing materials, elements, equipment or fixtures using new materials for the same purpose. This chapter is distinguished from Chapters 8 and 9 by only involving replacement of building components with new components with no reconfiguration of space.

    Chapter 8 Alterations—Level 2.

    A Level 2 alteration is an alteration involving space reconfiguration that could be up to and including 50 percent of the area of the building or addition of a new building system. Level 2 alterations also include the extension or addition of any system or equipment. The purpose of Chapter 8 is to provide detailed requirements and provisions to identify the required improvements in the existing building elements, means of egress, fire protection, structural systems, energy efficiency, and other building systems include electrical, mechanical and plumbing when a building is being altered.

    Chapter 9 Alterations—Level 3.

    Chapter 9 provides the technical requirements for those existing buildings that undergo Level 3 alterations. Level 3 alterations are those involving alterations that cover 50 percent of the aggregate area of the building. Under certain situations, this chapter also intends to improve the safety of certain building features beyond the work area and in other parts of the building where no alteration work might be taking place.

    Chapter 10 Change of Occupancy.

    The purpose of Chapter 10 is to address existing buildings that are subject to a change of occupancy. This chapter is an assembly of requirements to upgrade safety without having to comply fully as a new building. A change of occupancy classification is considered a change of occupancy, however, it will involve a higher level of regulation since the use of the building has made a more significant change.

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    Chapter 11 Additions.

    Chapter 11 provides the requirements for additions, which are considered new construction. The requirements focus on safely integrating the addition with the existing building. This includes issues such as limiting the overall height and area of the building where the addition is not separated by a fire wall.

    Chapter 12 Historic Buildings —Reserved

    Chapter 12 is not adopted by the State of California. Historic buildings and structures shall comply with Part 8, Title 24, California Code of Regulations.

    Chapter 13 Performance Compliance Methods.

    Chapter 13 allows for existing buildings to be evaluated to show that alterations or a change of occupancy, while not meeting new construction requirements, will provide a level of safety to demonstrate compliance. Provisions are based on a numerical scoring system involving 21 safety parameters where, when evaluated, such buildings must meet a minimum overall safety score.

  • CHBC § 170.1 High relevance — show source text

    b. Either:

    (i) Performance approach: Section 170.1; or (ii) Prescriptive approach: Section 170.2(a) through (f).

    F. Covered processes.

    i. Sections applicable. Sections 110.2, 120.3, 120.6, 140.9, and 141.1 apply to covered processes. ii. Compliance approaches. In order to comply with Part 6, covered processes must meet the requirements of: a. The applicable mandatory measures in Sections 110.2, 120.3 and 120.6; and

    b. Either:

    (i) The performance approach requirements of Section 140.1; or (ii) The prescriptive approach requirements of Section 140.9. 3. New construction in existing buildings (additions, alterations and repairs). A. Nonresidential and hotel/motel buildings. Section 141.0 applies to new construction in existing nonresidential, high-rise residential and hotel/motel buildings. New construction in existing buildings includes additions, alterations and repairs. Section 141.0 specifies requirements that uniquely apply to additions, alterations or repairs to existing buildings, and specify which requirements in other sections also apply. For alterations that change the occupancy classification of the building, the requirements specified in Section 141.0 apply to the occupancy after the alterations. B. Single-family buildings. Section 150.2 applies to new construction in existing single-family buildings. New construction in existing buildings includes additions, alterations and repairs. Section 150.2 specifies requirements that uniquely apply to additions, alterations or repairs to existing buildings, and specifies which requirements in other sections also apply. For alterations that change the occupancy classification of the building, the requirements specified in Section 150.2 apply to the occupancy after the alterations. C. Multifamily buildings. Section 180.0 applies to new construction in existing multifamily buildings. New construction in existing buildings includes additions, alterations and repairs. Section 180.0 specifies requirements that uniquely apply to additions, alterations or repairs to existing buildings, and specifies which requirements in other sections also apply. For alterations that change the occupancy classification of the building, the requirements specified in Section 180.0 apply to the occupancy after the alterations. 4. Installation of insulation in existing buildings. Section 110.8(d) applies to buildings in which insulation is being installed in existing attics, or on existing water heaters or existing space conditioning ducts. 5. Outdoor lighting. Sections 110.9, 130.0, 130.2, 130.4, 140.7, and 150.0 apply to newly constructed outdoor lighting systems, and Section 141.0 applies to outdoor lighting that is either added or altered. 6. Signs. Sections 130.0, 130.3 and 140.8 apply to newly constructed signs located either indoors or outdoors, and Section 141.0 applies to sign alterations located either indoors or outdoors.

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    ALL OCCUPANCIES—GENERAL PROVISIONS

    (f) Mixed occupancy. When a building is designed and constructed for more than one type of occupancy (residential and nonresidential), the space for each occupancy shall meet the provisions of Part 6 applicable to that occupancy.

  • 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 § 0.33 High relevance — show source text

    Exceptions:

    1. Where the area of the new occupancy is less than 10 percent of the building area, the occupancy is not changing from a Group S or Group U occupancy, and the new occupancy is not assigned to Risk Category IV, compliance with this section is not required. The cumulative effect of occupancy changes over time shall be considered.
    2. Where a change of use results in a building being reclassified from Risk Category I or II to Risk Category III and the seismic coefficient, S DS, is less than 0.33, compliance with this section is not required.
    3. Unreinforced masonry bearing wall buildings assigned to Risk Category III and to Seismic Design Category A or B, shall be permitted to use Appendix Chapter A1 of this code.
    4. Where the change is from a Group S or Group U occupancy and there is no change of risk category, compliance with Section 304.3.2 shall be permitted.

    [BS] 506.5.4 Access to Risk Category IV. Any structure that provides operational access to an adjacent structure assigned to Risk Category IV as the result of a change of occupancy shall itself comply with Sections 1608 and 1609 of the California Building Code and Section 304.3.1 of this code. Where operational access to the Risk Category IV structure is less than 10 feet (3048 mm) from either an interior lot line or from another structure, access protection from potential falling debris shall be provided.

    506.6 Enhanced classroom acoustics. In Group E occupancies, where the work area exceeds 50 percent of the building area, enhanced classroom acoustics shall be provided in all classrooms with a volume of 20,000 cubic feet (565 m [3] ) or less. Enhanced classroom acoustics shall comply with the reverberation time in Section 808 of ICC A117.1.

    SECTION 507—HISTORIC BUILDINGS

    507.1 Historic buildings. The provisions of the California Historical Building Code (Part 8, Title 24, C.C.R), shall apply to qualified historical buildings or properties.

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    CALIFORNIA EXISTING BUILDING CODE – MATRIX ADOPTION TABLE

    CHAPTER 5A – PRESCRIPTIVE COMPLIANCE METHOD [OSHPD 1]

    (Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)

  • CHBC § 8-3 High 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.

  • 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 § 8-303.6 Medium relevance — show source text

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

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

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

    8-303.8 Exiting. See Chapter 8-5.

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    8-4 FIRE PROTECTION

    SECTION 8-401 PURPOSE, INTENT AND SCOPE

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

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

    8-401.3 Scope. This chapter shall apply when required by the provisions of Section 8-102.

    SECTION 8-402 FIRE-RESISTIVE CONSTRUCTION

    8-402.1 Exterior wall construction. The fire-resistance requirement for existing exterior walls and existing opening protection may be satisfied when an automatic sprinkler system designed for exposure protection is installed per the CHBC. The automatic sprinklers may be installed on the exterior with at least one sprinkler located over each opening required to be protected. Additional sprinklers shall also be distributed along combustible walls under the roof lines that do not meet the fire-resistive requirement due to relationship to property lines as required by regular code. Such sprinkler systems may be connected to the domestic water supply on the supply-main side of the building shut-off valve. A shut-off valve may be installed for the sprinkler system, provided it is locked in an open position.

    8-402.2 One-hour construction. Upgrading an existing qualified historical building or property to one-hour fire-resistive construction and one-hour fire-resistive corridors shall not be required regardless of construction or occupancy when one of the following is provided:

    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

Frequently asked questions

Is every addition to a historic building allowed under the CHBC?

Yes — CHBC allows additions to qualified historical buildings, but nonhistorical additions must conform to the regular code; the CHBC intent is to facilitate preservation while ensuring safety. § 8‑102.1.1.

If I move a historic house, do I lose CHBC protections?

No — relocation of a qualified historical building/property is addressed by the CHBC; the relocated building must be sited to comply with the regular code or CHBC solutions, and any new nonhistoric construction related to the move must meet the regular code. § 8‑102.1.2.

Will changing a historic building from office to residential force full new‑construction compliance?

Not automatically — Chapter 8‑3 governs change of occupancy and the CHBC states such a change “shall not mandate conformance with new construction requirements” in the regular code; the building must meet CHBC requirements applicable to the new use. § 8‑302.2.

Who decides whether CHBC or regular code applies for part of a project?

The state or local enforcing agency administers and enforces the CHBC and determines application of CHBC alternatives when permits are issued; owners may elect CHBC application for qualified resources. § 8‑102.1.

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