CHBC · California Historical Building Code
What are "historical fabric or materials"?
“Historical fabric or materials” in the California Historical Building Code means original and later‑added construction materials, finishes, or elements (including patterns or configurations) that give a property its historic identity; whether a particular item meets that definition is decided by the local/state enforcing agency (AHJ), and the CHBC encourages in‑kind repair and preservation when feasible. **§ 8-201**.
Last reviewed: July 6, 2026
What the code requires — plain English
The California Historical Building Code defines HISTORICAL FABRIC OR MATERIALS as original and later‑added historically significant construction materials, architectural finishes or elements in a particular pattern or configuration which form a qualified historical property, as determined by the authority having jurisdiction — § 8-201.
The single most important point: if a material or element is part of the building’s historically significant materials or finishes (original or later added) and contributes to the property’s historic identity, it is “historical fabric or materials” — and that determination is made by the authority having jurisdiction. § 8-201.
Requirements in detail
Defined term (bolded): HISTORICAL FABRIC OR MATERIALS — includes both original materials and later‑added materials that are historically significant, and the items are considered in the context of a particular pattern or configuration that helps make the property a qualified historical resource. The final determination is made by the authority having jurisdiction. § 8-201.
Key implications (derived from the definition plus adjacent CHBC provisions):
- Preservation decisions focus on what contributes to the property’s historic identity (materials, finishes, elements, patterns).
- The local/state enforcing agency (authority having jurisdiction) is the deciding body for whether particular materials/elements are part of the historical fabric. § 8-201.
- Where work is proposed, the CHBC allows repairs to be made “in‑kind” with historical materials and methods when appropriate (see § 8-105.1).
Decision-relevant dimensions (quick reference table)
| Decision dimension | What to look for / typical values | Why it matters | Code Reference |
|---|---|---|---|
| Is the material original or later‑added? | Original (built with the building) OR later additions that have become historically significant | Both categories are included in the definition of historical fabric | § 8-201 |
| Is it historically significant? | Significance determined by AHJ based on period/character; no numeric threshold in § 8-201 | Only historically significant items are treated as historical fabric | § 8-201 |
| Is the material part of a pattern or configuration? | E.g., continuous cornice, siding profile, window grouping, decorative trim | Pattern/configuration can make otherwise mundane materials part of historic fabric | § 8-201 |
| Who decides? | Authority having jurisdiction (AHJ) — local or state enforcing agency | AHJ’s determination controls whether CHBC protections apply | § 8-201 |
| What work is allowed? | In‑kind repairs and use of historical methods/materials are permitted subject to CHBC conditions | Enables retention/repair of historical fabric rather than replacement with nonhistoric materials | § 8-105.1 |
Short explanation of each table row
- “Original vs later‑added”: § 8-201 explicitly includes both. The code does not limit the term to only the elements first installed at original construction.
- “Historically significant”: significance is a qualitative determination (not a numeric test) made by the AHJ; the CHBC relies on that determination to decide whether CHBC treatments apply.
- “Pattern or configuration”: the definition calls out materials/elements “in a particular pattern or configuration,” so repeated or integrated arrangements (façade rhythm, trim profiles) can be decisive.
- “Who decides?”: the phrase “as determined by the authority having jurisdiction” places the responsibility with the enforcing agency.
Exceptions & special cases
- The CHBC definition does not create absolute immunity for historic materials where there is a distinct hazard or imminent threat — separate CHBC sections (and regular code processes) still govern hazards; the AHJ may require mitigation if life‑safety is at risk. The CHBC defines “distinct hazard” and describes appeals processes elsewhere in Chapter 8. § 8-201 defines the term and other sections address hazards and appeals.
- The code does not prescribe a quantitative percentage (for example, “X% original material must remain”) in § 8-201. Whether material is part of the historical fabric is a qualitative, documentation‑driven determination by the AHJ.
- Repairs “in‑kind” with historical materials and original methods are explicitly permitted (subject to CHBC conditions and other chapters), which is a special allowance compared to regular code requirements. See § 8-105.1.
Common mistakes
- Assuming “old” = “historical fabric.” Age alone does not make a material part of the historical fabric — it must be historically significant and contribute to the property’s historical identity as determined by the AHJ. § 8-201.
- Thinking the AHJ cannot reclassify later additions as historical — the definition explicitly includes later‑added historically significant materials. § 8-201.
- Expecting numerical thresholds (e.g., percent of original fabric required) in § 8-201 — none are given; decisions are evidence‑based and case specific.
- Replacing historic materials with modern substitutes without AHJ approval. The CHBC supports in‑kind repairs; wholesale substitution may remove CHBC protections and trigger regular code requirements. See § 8-105.1.
Worked example — concrete scenario with numbers
Scenario: A homeowner owns a two‑story, 2,000 ft² house built in 1910. The house has:
- 800 ft² of original wood clapboard siding,
- 24 ft² of original stained‑glass windows (six windows, each 4 ft²),
- a later‑added front porch (added 1940) with decorative turned balusters that the local historical commission regards as character‑defining.
Application of the definition:
Are these items “historical fabric or materials”? The original clapboard and stained‑glass windows are candidate historical fabric because they are original. The porch balusters — though later‑added — may also be included because the definition covers later‑added historically significant elements and patterns (porch baluster pattern contributes to character). The AHJ will make the formal determination per § 8-201.
If the homeowner wants to replace 400 ft² (50%) of the clapboard with vinyl: before proceeding the owner should consult the AHJ. The CHBC allows in‑kind repairs; replacing historic clapboard with vinyl would likely be considered removal of historical fabric and may not be permitted under CHBC policy unless the AHJ approves an alternative. See § 8-105.1 for the allowance of in‑kind repairs and methods.
If the owner instead proposes to repair the clapboard in‑kind (replace 200 ft² of badly deteriorated boards with matching wood profiles): that repair method is expressly contemplated by the CHBC and aligns with preserving historical fabric as defined in § 8-201. The AHJ would document and accept that work under CHBC procedures.
Key takeaways from the scenario:
- Quantities (e.g., 400 ft² vs 200 ft²) matter practically (extent of work) but do not change the legal definition — the AHJ’s historic‑fabric determination and acceptance of in‑kind work are controlling under § 8-201 and § 8-105.1.
Related provisions (CHBC sections to consult)
- § 8-201 — Definitions (primary definition of “historical fabric or materials”).
- § 8-105.1 — Repairs: allows repairs “in‑kind” with historical materials and methods (useful when applying the definition).
- § 8-801.3 — Scope: explains that construction types or materials that are, or were, part of the historical fabric are covered (context for archaic materials).
- § 8-703.1–8-703.3 — Structural survey requirements: when historical materials are part of structural systems, these sections guide documentation and evaluation.
- § 8-602.1–8-603 — Accessibility alternatives when strict compliance would threaten character‑defining features (relates to decisions about altering historical fabric).
- § 8-104.3 — Appeals to the State Historical Building Safety Board (if AHJ decisions over historical fabric are disputed).
Code references
Grounded in the retrieved California Historical Building Code — click a citation to read the verbatim passage:
CHBC § 8-706.3 High relevance — show source text
8-706.3 Load path. A complete and continuous load path, including connections, from every part or portion of the structure to the ground shall be provided for the required forces. It shall be verified that the structure is adequately tied together to perform as a unit when subjected to earthquake forces.
8-706.4 Parapets. Parapets and exterior decoration shall be investigated for conformance with regular code requirements for anchorage and ability to resist prescribed seismic forces.
An exception to regular code requirements shall be permitted for those parapets and decorations which are judged not to be a hazard to life safety.
8-706.5 Nonstructural features. Nonstructural features of historical structure, such as exterior veneer, cornices and decorations, which might fall and create a life safety hazard in an earthquake, shall be evaluated. Their ability to resist seismic forces shall be verified, or the feature shall be strengthened with improved anchorage when appropriate.
8-706.5.1 Partitions and ceilings of corridors and stairways serving an occupant load of 30 or more shall be investigated to determine their ability to remain in place when the building is subjected to earthquake forces.
8-706.5.2 Seismic forces used to evaluate and improve nonstructural components and their anchorage, where required, shall comply with ASCE 41 or need not exceed 0.75 times the seismic forces prescribed by the requirements of the regular code.
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8-8 ARCHAIC MATERIALS AND METHODS OF CONSTRUCTION
SECTION 8-801 — PURPOSE, INTENT AND SCOPE
8-801.1 Purpose. The purpose of the CHBC is to provide regulations for the use of historical methods and materials of construction that are at variance with regular code requirements or are not otherwise codified, in buildings or structures designated as qualified historical buildings or properties. The CHBC require enforcing agencies to accept any reasonably equivalent alternatives to the regular code when dealing with qualified historical buildings or properties.
8-801.2 Intent. It is the intent of the CHBC to provide for the use of historical methods and materials of construction that are at variance with specific code requirements or are not otherwise codified.
8-801.3 Scope. Any construction type or material that is, or was, part of the historical fabric of a structure is covered by this chapter. Archaic materials and methods of construction present in a historical structure may remain or be reinstalled or be installed with new materials of the same class to match existing conditions.
SECTION 8-802 — GENERAL ENGINEERING APPROACHES
Strength values for archaic materials shall be assigned based upon similar conventional codified materials, or on tests as hereinafter indicated. The archaic materials and methods of construction shall be thoroughly investigated for their details of construction in accordance with Section 8-703. Testing shall be performed when applicable to evaluate existing conditions. The architect or structural engineer in responsible charge of the project shall assign allowable stresses or strength levels to archaic materials. Such assigned strength values shall not be greater than those provided for in the following sections without adequate testing, and shall be subject to the concurrence of the enforcing agency.
SECTION 8-803 — NONSTRUCTURAL ARCHAIC MATERIALS
CHBC § 8-801 High relevance — show source text
SECTION 8-801 — PURPOSE, INTENT AND SCOPE
8-801.1 Purpose. The purpose of the CHBC is to provide regulations for the use of historical methods and materials of construction that are at variance with regular code requirements or are not otherwise codified, in buildings or structures designated as qualified historical buildings or properties. The CHBC require enforcing agencies to accept any reasonably equivalent alternatives to the regular code when dealing with qualified historical buildings or properties.
8-801.2 Intent. It is the intent of the CHBC to provide for the use of historical methods and materials of construction that are at variance with specific code requirements or are not otherwise codified.
8-801.3 Scope. Any construction type or material that is, or was, part of the historical fabric of a structure is covered by this chapter. Archaic materials and methods of construction present in a historical structure may remain or be reinstalled or be installed with new materials of the same class to match existing conditions.
SECTION 8-802 — GENERAL ENGINEERING APPROACHES
Strength values for archaic materials shall be assigned based upon similar conventional codified materials, or on tests as hereinafter indicated. The archaic materials and methods of construction shall be thoroughly investigated for their details of construction in accordance with Section 8-703. Testing shall be performed when applicable to evaluate existing conditions. The architect or structural engineer in responsible charge of the project shall assign allowable stresses or strength levels to archaic materials. Such assigned strength values shall not be greater than those provided for in the following sections without adequate testing, and shall be subject to the concurrence of the enforcing agency.
SECTION 8-803 — NONSTRUCTURAL ARCHAIC MATERIALS
Where nonstructural historical materials exist in uses which do not meet the requirements of the regular code, their continued use is allowed by this code, provided that any public health and life safety hazards are mitigated subject to the concurrence of the enforcing agency.
SECTION 8-804 — ALLOWABLE CONDITIONS FOR SPECIFIC MATERIALS
Archaic materials which exist and are to remain in qualified historical buildings or structures shall be evaluated for their condition and for loads required by this code. The structural survey required in Section 8-703 of the CHBC shall document existing conditions, reinforcement, anchorage, deterioration and other factors pertinent to establishing allowable stresses, strength levels and adequacy of the archaic materials. The remaining portion of this chapter provides additional specific requirements for commonly encountered archaic materials.
SECTION 8-805 — MASONRY
For adobe, see Section 8-806.
8-805.1 Existing solid masonry. Existing solid masonry walls of any type, except adobe, may be allowed, without testing, a maximum ultimate strength of 9 pounds per square inch (62.1 kPa) in shear where there is a qualifying statement by the architect or engineer that an inspection has been made, that mortar joints are filled and that both brick and mortar are reasonably good. The shear stress above applies to unreinforced masonry, except adobe, where the maximum ratio of unsupported height or length to thickness does not exceed 13, and where minimum quality mortar is used or exists. Wall height or length is measured to supporting or resisting elements that are at least twice as stiff as the tributary wall. Stiffness is based on the gross section. Shear stress may be increased by the addition of 10 percent of the axial direct stress due to the weight of the wall directly above.
CHBC § 8-2 High relevance — show source text
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8-2 DEFINITIONS
SECTION 8-201 — DEFINITIONS
For the purpose of the CHBC, certain terms and phrases, words and their derivatives shall be construed as specified in this chapter. Additional definitions and/or terms may appear in the various other chapters relative to terms or phrases primarily applicable thereto. Any reference to “authority having jurisdiction” does not necessarily preclude the appellate process of Section 8-104.3.
ADDITION. A nonhistorical extension or increase in floor area or height of a building or property.
ALTERATION. A modification to a qualified historical building or property that affects the usability of the building or property, or part thereof. Alterations include, but are not limited to, remodeling, renovation, rehabilitation, reconstruction, historical restoration, changes or rearrangement of the structural parts or elements, and changes or rearrangements in the plan configuration of walls and full-height partitions.
BUILDING STANDARD. Any guideline, regulation or code that may be applied to a qualified historical building or property.
CHARACTER-DEFINING FEATURE. Those visual aspects and physical elements that comprise the appearance of a historical building or property, and that are significant to its historical, architectural and cultural values, including the overall shape of the historical building or property, its materials, craftsmanship, decorative details, interior spaces and features, as well as the various aspects of its site and environment.
CULTURAL RESOURCE. Building, site, property, object or district evaluated as having significance in prehistory or history.
DISTINCT HAZARD. Any clear and evident condition that exists as an immediate danger to the safety of the occupants or public right of way. Conditions that do not meet the requirements of current regular codes and ordinances do not, of themselves, constitute a distinct hazard. Section 8-104.3, SHBC appeals, remains applicable.
ENFORCING AGENCY, Authority Having Jurisdiction, Local Agency with Jurisdiction. An entity with the responsibility for regulating, enforcing, reviewing or otherwise that exerts control of or administration over the process of granting permits, approvals, decisions, variances, appeals for qualified historical buildings or properties.
EXIT LADDER DEVICE. An exit ladder device is a permanently installed, fixed, folding, retractable or hinged ladder intended for use as a means of emergency egress from areas of the second or third stories. Unless approved specifically for a longer length, the ladder shall be limited to 25 feet (7620 mm) in length. Exit ladders are permitted where the area served by the ladder has an occupant load less than 10 persons.
FIRE HAZARD. Any condition which increases or may contribute to an increase in the hazard or menace of fire to a greater degree than customarily recognized by the authority having jurisdiction, or any condition or act which could obstruct, delay, hinder or interfere with the operations of firefighting personnel or the egress of occupants in the event of fire. Section 8-104.3, SHBC appeals, remains applicable.
HISTORICAL FABRIC OR MATERIALS. Original and later-added historically significant construction materials, architectural finishes or elements in a particular pattern or configuration which form a qualified historical property, as determined by the authority having jurisdiction.
HISTORICAL SIGNIFICANCE. Importance for which a property has been evaluated and found to be historical, as determined by the authority having jurisdiction.
CHBC § 8-104.3 High relevance — show source text
ENFORCING AGENCY, Authority Having Jurisdiction, Local Agency with Jurisdiction. An entity with the responsibility for regulating, enforcing, reviewing or otherwise that exerts control of or administration over the process of granting permits, approvals, decisions, variances, appeals for qualified historical buildings or properties.
EXIT LADDER DEVICE. An exit ladder device is a permanently installed, fixed, folding, retractable or hinged ladder intended for use as a means of emergency egress from areas of the second or third stories. Unless approved specifically for a longer length, the ladder shall be limited to 25 feet (7620 mm) in length. Exit ladders are permitted where the area served by the ladder has an occupant load less than 10 persons.
FIRE HAZARD. Any condition which increases or may contribute to an increase in the hazard or menace of fire to a greater degree than customarily recognized by the authority having jurisdiction, or any condition or act which could obstruct, delay, hinder or interfere with the operations of firefighting personnel or the egress of occupants in the event of fire. Section 8-104.3, SHBC appeals, remains applicable.
HISTORICAL FABRIC OR MATERIALS. Original and later-added historically significant construction materials, architectural finishes or elements in a particular pattern or configuration which form a qualified historical property, as determined by the authority having jurisdiction.
HISTORICAL SIGNIFICANCE. Importance for which a property has been evaluated and found to be historical, as determined by the authority having jurisdiction.
IMMINENT THREAT. Any condition within or affecting a qualified historical building or property which, in the opinion of the authority having jurisdiction, would qualify a building or property as dangerous to the extent that the life, health, property or safety of the public, its occupants or those performing necessary repair, stabilization or shoring work are in immediate peril due to conditions affecting the building or property. Potential hazards to persons using, or improvements within, the right-of-way may not be construed to be “imminent threats” solely for that reason if the hazard can be mitigated by shoring, stabilization, barricades or temporary fences.
INTEGRITY. Authenticity of a building or property’s historical identity, evidenced by the survival of physical characteristics that existed during the property’s historical or prehistorical period of significance.
LIFE SAFETY EVALUATION. An evaluation of the life safety hazards of a qualified historical building or property based on procedures similar to those contained in NFPA 909, Standard for the Protection of Cultural Resources, Appendix B, Fire Risk Assessment in Heritage Premises.
LIFE SAFETY HAZARD. See Distinct Hazard.
PERIOD OF SIGNIFICANCE. The period of time when a qualified historical building or property was associated with important events, activities or persons, or attained the characteristics for its listing or registration.
PRESERVATION. The act or process of applying measures necessary to sustain the existing form, integrity and materials of a qualified historical building or property. Work, including preliminary measures to protect and stabilize the property, generally focuses upon the ongoing maintenance and repair of historic materials and features rather than extensive replacement and new construction. New exterior additions are not within the scope of this treatment; however, the limited and sensitive upgrading of mechanical,
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DEFINITIONS
electrical and plumbing systems and other code-related work to make properties functional is appropriate within a preservation project.
CHBC § 8-1 Medium relevance — show source text
CONTENTS
CHAPTER 8-1 ADMINISTRATION . . . . . . . . . . . . . . . . . . . . . . . 1
Section
8-101 Title, Purpose and Intent. . . . . . . . . . . . . . . . . . . . . . . . . 1 8-102 Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 8-103 Organization and Enforcement . . . . . . . . . . . . . . . . . . . 1 8-104 Review and Appeals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 8-105 Construction Methods and Materials . . . . . . . . . . . . . . 2
8-106 SHBSB Rulings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
CHAPTER 8-2 DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Section
8-201 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
CHAPTER 8-3 USE AND OCCUPANCY . . . . . . . . . . . . . . . . . . . 5
Section
8-301 Purpose and Scope. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 8-302 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
8-303 Residential Occupancies. . . . . . . . . . . . . . . . . . . . . . . . . 5
CHAPTER 8-4 FIRE PROTECTION. . . . . . . . . . . . . . . . . . . . . . . 7
Section
8-401 Purpose, Intent and Scope . . . . . . . . . . . . . . . . . . . . . . . 7
8-402 Fire-resistive Construction . . . . . . . . . . . . . . . . . . . . . . . 7
8-403 Interior Finish Materials. . . . . . . . . . . . . . . . . . . . . . . . . . 7
8-404 Wood Lath and Plaster. . . . . . . . . . . . . . . . . . . . . . . . . . . 7
8-405 Occupancy Separation . . . . . . . . . . . . . . . . . . . . . . . . . . 7 8-406 Maximum Floor Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
CHBC § 8-1001 Medium relevance — show source text
Section
8-1001 Purpose and Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 8-1002 Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 8-1003 Site Relations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
APPENDIX A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
HISTORY NOTE APPENDIX . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
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8-1 ADMINISTRATION
Note: The California Historical Building Code, Part 8 of Title 24, governs for all qualified historical buildings or properties in the State of California.
SECTION 8-101 — TITLE, PURPOSE AND INTENT
8-101.1 Title. These regulations shall be known as the California Historical Building Code and will be referred to herein as “the CHBC.”
8-101.2 Purpose. The purpose of the CHBC is to provide regulations for the preservation, restoration, rehabilitation, relocation or reconstruction of buildings or properties designated as qualified historical buildings or properties (as defined in Chapter 8-2). The CHBC is intended to provide solutions for the preservation of qualified historical buildings or properties, to promote sustainability, to provide access for persons with disabilities, to provide a cost-effective approach to preservation, and to provide for the reasonable safety of the occupants or users. The CHBC requires enforcing agencies to accept solutions that are reasonably equivalent to the regular code (as defined in Chapter 8-2) when dealing with qualified historical buildings or properties.
8-101.3 Intent. The intent of the CHBC is to facilitate the preservation and continuing use of qualified historical buildings or properties while providing reasonable safety for the building occupants and access for persons with disabilities.
SECTION 8-102 — APPLICATION
8-102.1 Application. The CHBC is applicable to all issues regarding code compliance for qualified historical buildings or properties. The CHBC may be used in conjunction with the regular code to provide solutions to facilitate the preservation of qualified historical buildings or properties. The CHBC shall be used by any agency with jurisdiction and whenever compliance with the code is required for qualified historical buildings or properties.
- State or local enforcing agency. The state or local enforcing agency shall apply the provisions of the CHBC in permitting repairs, alterations and additions necessary for the preservation, restoration, reconstruction, rehabilitation, relocation or continued use of a qualified historical building or property when so elected by the private property owner.
- **State agencies.
CHBC § 8-1001.1 Medium relevance — show source text
8-1001.1 Purpose. The purpose of this chapter is to provide regulations for the preservation, rehabilitation, restoration and reconstruction of associated historical features of qualified historical buildings, properties or districts (as defined in Chapter 8-2), and for which Chapters 8-3 through 8-9 of the CHBC may not apply.
8-1001.2 Scope. This chapter applies to the associated historical features of qualified historical buildings or properties such as historical districts that are beyond the buildings themselves which include, but are not limited to, natural features and designed site and landscape plans with natural and man-made landscape elements that support their function and aesthetics. This may include, but will not be limited to:
- Site plan layout configurations and relationships (pedestrian, equestrian and vehicular site circulation, topographical grades and drainage, and use areas).
- Landscape elements (plant materials, site structures other than the qualified historical building, bridges and their associated structures, lighting, water features, art ornamentation, and pedestrian, equestrian and vehicular surfaces).
- Functional elements (utility placement, erosion control and environmental mitigation measures).
SECTION 8-1002 — APPLICATION
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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CHBC § 8-104.4 Medium relevance — show source text
8-104.4 Local agency fees. Local agencies, when actively involved in the appeal, may also charge affected persons reasonable fees not to exceed the cost of obtaining reviews and appeals from the Board.
SECTION 8-105 — CONSTRUCTION METHODS AND MATERIALS
8-105.1 Repairs. Repairs to any portion of a qualified historical building or property may be made in-kind with historical materials and the use of original or existing historical methods of construction, subject to conditions of the CHBC. (See Chapter 8-8.)
8-105.2 Solutions to the California Historical Building Code . Solutions provided in the CHBC, or any other acceptable regulation or methodology of design or construction and used in whole or in part, with the regular code, or with any combination of the regular code and the CHBC, shall be allowed. The CHBC does not preclude the use of any proposed alternative or method of design or construction not specifically prescribed or otherwise allowed by these regulations. Any alternative may be submitted for evaluation to the appropriate enforcing agency for review and acceptance. The enforcing agency may request that sufficient evidence or proof be submitted to substantiate any claims that may be made regarding such solutions. Any alternative offered in lieu of that prescribed or allowed in the CHBC shall be reasonably equivalent in quality, strength, effectiveness, durability and safety to that of the CHBC.
SECTION 8-106 — SHBSB RULINGS
8-106.1 General. Rulings of the SHBSB (i.e., formal appeals, case decisions, code interpretations and administrative resolutions, etc.) that are issues of statewide application are required to be submitted to the California Building Standards Commission in printed form. These rulings may be used to provide guidance for similar cases or issues.
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8-2 DEFINITIONS
SECTION 8-201 — DEFINITIONS
For the purpose of the CHBC, certain terms and phrases, words and their derivatives shall be construed as specified in this chapter. Additional definitions and/or terms may appear in the various other chapters relative to terms or phrases primarily applicable thereto. Any reference to “authority having jurisdiction” does not necessarily preclude the appellate process of Section 8-104.3.
ADDITION. A nonhistorical extension or increase in floor area or height of a building or property.
ALTERATION. A modification to a qualified historical building or property that affects the usability of the building or property, or part thereof. Alterations include, but are not limited to, remodeling, renovation, rehabilitation, reconstruction, historical restoration, changes or rearrangement of the structural parts or elements, and changes or rearrangements in the plan configuration of walls and full-height partitions.
BUILDING STANDARD. Any guideline, regulation or code that may be applied to a qualified historical building or property.
CHARACTER-DEFINING FEATURE. Those visual aspects and physical elements that comprise the appearance of a historical building or property, and that are significant to its historical, architectural and cultural values, including the overall shape of the historical building or property, its materials, craftsmanship, decorative details, interior spaces and features, as well as the various aspects of its site and environment.
CULTURAL RESOURCE. Building, site, property, object or district evaluated as having significance in prehistory or history.
CHBC § 8-6 Medium relevance — show source text
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APPENDIX A Col2 Col3 Col4 CHAPTER 8-6—TABLE 1—PROVISION APPLICABILITY CHAPTER 8-6—TABLE 1—PROVISION APPLICABILITY CHAPTER 8-6—TABLE 1—PROVISION APPLICABILITY CHAPTER 8-6—TABLE 1—PROVISION APPLICABILITY Title II
Public EntitiesTitle III
Private EntitiesTitle III
Barrier RemovalSECTION 8-601 PURPOSE, INTENT, SCOPE
**8-601.1 Purpose.**The purpose of the CHBC is to provide alternative regulations to facilitate
access and use by persons with disabilities to and throughout facilities designated as quali-
fied historical buildings or properties. These regulations require enforcing agencies to
accept alternatives to regular code when dealing with qualified historical buildings or
properties.
**8-601.2 Intent.**The intent of this chapter is to preserve the integrity of qualified historical
buildings and properties while providing access to and use by persons with disabilities.
**8-601.3 Scope.**The CHBC shall apply to every qualified historical building or property that
is required to provide access to persons with disabilities.
1.Provisions of this chapter do not apply to new construction or reconstruction/replicas of
historical buildings.
2. Where provisions of this chapter apply to alteration of qualified historical buildings or
properties, alteration is defined in_ California Building Code_ (CBC), Chapter 2.
8-601.4 General application. The provisions in the CHBC apply to local, state and federal
governments (Title II entities); alteration of commercial facilities and places of public
accommodation (Title III entities); and barrier removal in commercial facilities and places of
public accommodation (Title III entities). Except as noted in this chapter.Applies Applies Applies SECTION 8-602 — BASIC PROVISIONS
8-602.1 Regular code. The regular code for access for people with disabilities (Title 24, Part
2, Vol.1, Chapter 11B) shall be applied to qualified historical buildings or properties unless
strict compliance with the regular code will threaten or destroy the historical significance or
character-defining features of the building or property.
**8-602.2 Alternative provisions.**If the historical significance or character-defining features
are threatened, alternative provisions for access may be applied pursuant to this chapter,
provided the following conditions are met:
1.These provisions shall be applied only on an item-by-item or case-by-case basis.
2.Documentation is provided, including meeting minutes or letters, stating the reasons
for the application of the alternative provisions. Such documentation shall be retained
in the permanent file of the enforcing agency.Applies Applies Applies Section 8-603 — ALTERNATIVES
**8-603.1 Alternative minimum standards.**The alternative minimum standards for alter-
ations of qualified historical buildings or facilities are referenced in Section 202.5 of the_ 2010_
ADA Standards for Accessible Design, as incorporated and set forth in federal regulation 28
CFR Pt. 36.
**8-603.2 Entry.CHBC § 8-1 Medium relevance — show source text
After further development and refinement, the enacting legislation to create the authority for the code and an advisory board to prepare regulations to implement it (SB 927, Mills) was supported by both the legislature and the public. It was signed by the governor in September 1975, and became effective January 1, 1976. The members of the advisory board, which were required by law to include local and state building officials, individuals from the building industry and design professions, as well as representatives from city and county governments, were appointed and held their first session in Sacramento on February 24, 1976. This Board’s duties included the preparation of code regulations and the review of specific historic building cases, when officially requested by governing bodies. Several of the Board’s members were a part of the original ad hoc steering committee and thus provided a continuity and smooth transition from the inception of the code’s philosophy to its pragmatic implementation in these performance–oriented regulations. The first comprehensive regulations were codified in August and October 1979, after years of careful deliberation. Those regulations allowed all jurisdictions to utilize them at their discretion in replacing or modifying details of prevailing prescriptive codes. Changes made in law in 1984 and 1991, and to the code, make the application of the California Historical Building Code statutes and regulations applicable for all agencies and at the discretion of the owner for local jurisdictions when dealing with qualified historical buildings. These current performance regulations were adopted by the Board on June 23, 1998.
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CONTENTS
CHAPTER 8-1 ADMINISTRATION . . . . . . . . . . . . . . . . . . . . . . . 1
Section
8-101 Title, Purpose and Intent. . . . . . . . . . . . . . . . . . . . . . . . . 1 8-102 Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 8-103 Organization and Enforcement . . . . . . . . . . . . . . . . . . . 1 8-104 Review and Appeals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 8-105 Construction Methods and Materials . . . . . . . . . . . . . . 2
8-106 SHBSB Rulings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
CHAPTER 8-2 DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Section
8-201 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
CHAPTER 8-3 USE AND OCCUPANCY . . . . . . . . . . . . . . . . . . . 5
Section
CHBC § 1507.7.8 Medium relevance — show source text
1507.7.8 Additional requirements. [DSA-SS & DSA-SS/CC, OSHPD 1, 1R, 2, 4 & 5] In addition to the requirements of Section 1507.7.5, the installation of slate shingle roof coverings shall comply with the requirements of Sections 1507.3.6 and 1507.3.7, and the seismic anchorage provisions of Section 1513.
1507.8 Wood shingles. The installation of wood shingles shall comply with the provisions of this section and Table 1507.8.
TABLE 1507.8—WOOD SHINGLE AND SHAKE INSTALLATION Col2 Col3 ROOF ITEM WOOD SHINGLES WOOD SHAKES 1. Roof slope Wood shingles shall be installed on slopes of
not less than 3 units vertical in 12 units hori-
zontal (3:12).Wood shakes shall be installed on slopes of not less
than 4 units vertical in 12 units horizontal (4:12).2. Deck requirement 2. Deck requirement 2. Deck requirement Temperate climate Shingles shall be applied to roofs with solid or
spaced sheathing. Where spaced sheathing is
used, sheathing boards shall be not less than
1″ × 4″ nominal dimensions and shall be
spaced on centers equal to the weather expo-
sure to coincide with the placement of
fasteners.Shakes shall be applied to roofs with solid or spaced
sheathing. Where spaced sheathing is used, sheath-
ing boards shall be not less than 1″ × 4″ nominal
dimensions and shall be spaced on centers equal to
the weather exposure to coincide with the placement
of fasteners. Where 1″ × 4″ spaced sheathing is
installed at 10 inches, boards must be installed
between the sheathing boards.In areas where the average daily
temperature in January is 25°F or
less or where there is a possibility
of ice forming along the eaves
causing a backup of water.Solid sheathing is required. Solid sheathing is required. 3. Interlayment No requirements. Interlayment shall comply with ASTM D226, Type 1. 4. Underlayment 4. Underlayment 4. Underlayment Temperate climate Underlayment shall comply with Section
1507.1.1.Underlayment shall comply with Section 1507.1.1. 5. Application 5. Application 5. Application Attachment Fasteners for wood shingles shall be hot-
dipped galvanized or Type 304 (Type 316 for
coastal areas) stainless steel with a minimum
penetration of 0.75 inch into the sheathing.
For sheathing less than 0.5 inch thick, the
fasteners shall extend through the sheathing.Fasteners for wood shakes shall be hot-dipped galva-
nized or Type 304 (Type 316 for coastal areas) with a
minimum penetration of 0.75 inch into the sheath-
ing. For sheathing less than 0.5 inch thick, the
fasteners shall extend through the sheathing.No. CHBC § 8-702.2 Medium relevance — show source text
8-702.2 Nothing in these regulations shall prevent voluntary and partial seismic upgrades when it is demonstrated that such upgrades will improve life safety and when a full upgrade would not otherwise be required.
SECTION 8-703 — STRUCTURAL SURVEY
8-703.1 Scope. When a structure or portion of a structure is to be evaluated for structural capacity under the CHBC, it shall be surveyed for structural conditions by an architect or engineer knowledgeable in historical structures. The survey shall evaluate deterioration or signs of distress. The survey shall determine the details of the structural framing and the system for resistance of gravity and lateral loads. Details, reinforcement and anchorage of structural systems and veneers shall be determined and documented where these members are relied on for seismic lateral resistance.
8-703.2 The results of the survey shall be utilized for evaluating the structural capacity and for designing modifications to the structural system to reach compliance with this code.
8-703.3 Historical records. Past historical records of the structure or similar structures may be used in the evaluation, including the effects of subsequent alterations.
SECTION 8-704 — NONHISTORICAL ADDITIONS AND NONHISTORICAL ALTERATIONS
8-704.1 New nonhistorical additions and nonhistorical alterations which are structurally separated from an existing historical building or structure shall comply with regular code requirements.
8-704.2 New nonhistorical additions which impose vertical or lateral loads on an existing structure shall not be permitted unless the affected part of the supporting structure is evaluated and strengthened, if necessary, to meet regular code requirements.
Note: For use of archaic materials, see Chapter 8-8.
SECTION 8-705 — STRUCTURAL REGULATIONS
8-705.1 Gravity loads. The capacity of the structure to resist gravity loads shall be evaluated and the structure strengthened as necessary. The evaluation shall include all parts of the load path. Where no distress is evident, and a complete load path is present, the structure may be assumed adequate by having withstood the test of time if anticipated dead and live loads will not exceed those historically present.
8-705.2 Wind and seismic loads. The ability of the structure to resist wind and seismic loads shall be evaluated. Wind loads shall be considered when appropriate, but need not exceed 75 percent of the wind loads prescribed by the regular code. The evaluation shall be based on the requirements of Section 8-706.
8.705.2.1 Any unsafe conditions in the lateral-load-resisting system shall be corrected, or alternative resistance shall be provided. When strengthening is required, additional resistance shall be provided to meet the minimum requirements of the CHBC. The strengthening measures shall be selected with the intent of meeting the performance objectives set forth in Section 8-701.2. The evaluation of structural members and structural systems for seismic loads shall consider the inelastic performance of structural members and their ability to maintain load-carrying capacity during the seismic loadings prescribed by the regular code.
8.705.2.2 The architect or engineer shall consider additional measures with minimal loss of, and impact to, historical materials which will reduce damage and needed repairs in future earthquakes to better preserve the historical structure in perpetuity. These additional measures shall be presented to the owner for consideration as part of the rehabilitation or restoration.
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STRUCTURAL REGULATIONS
Frequently asked questions
Who decides whether something is part of the “historical fabric or materials”?
The authority having jurisdiction (AHJ) — the local or state enforcing agency — makes the determination under the CHBC definition in § 8-201.
Does “historical fabric” include later additions?
Yes. The definition explicitly includes later‑added historically significant materials or elements when they contribute to the property’s historic identity. § 8-201.
If a material is part of the historical fabric, must it always be preserved?
Not absolutely — life‑safety hazards or imminent threats may require mitigation; the AHJ balances preservation with safety. The CHBC also permits in‑kind repairs and other treatments to preserve materials where feasible. See § 8-201 for the definition and § 8-105.1 for repairs.
Are there numeric thresholds (percent of original material) in the CHBC definition?
No. § 8-201 defines the term qualitatively; the code does not set percentage thresholds for what constitutes historical fabric. The AHJ’s documented determination and context drive decisions.
Can I perform in‑kind repairs myself?
The CHBC permits repairs “in‑kind” with historical materials and original methods subject to CHBC conditions and AHJ oversight; check § 8-105.1 and coordinate permits with the enforcing agency.
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