CHBC · California Historical Building Code

When can historical records or material testing be used to establish capacity?

The CHBC allows engineers to use historical records and material testing to establish the capacity of historic elements, but a qualified architect/engineer must document a current survey and justify assigned strengths. Default CHBC allowances (for example, 9 psi shear for certain solid masonry) can be used only when inspection criteria are met; otherwise representative testing and enforcing‑agency concurrence are required.

Last reviewed: July 6, 2026

What the code requires — plain English

The CHBC permits using past historical records and material testing to establish the strength or capacity of existing historical components when evaluating a qualified historical building. The controlling provisions are § 8-703.3 (use of historical records) and § 8-802 (assigning strength values for archaic materials based on conventional equivalents or tests) .

The single most important rule: if an architect or engineer documents existing conditions and demonstrates that the historical record or representative tests reliably reflect current capacity, those records/tests may be used to assign allowable stresses or strength levels under the CHBC.

Requirements in detail

Who must do the evaluation

  • A qualified architect or engineer knowledgeable in historical structures must perform the structural survey and make the evaluation (see § 8-703.1) .
  • That same design professional assigns allowable stresses / strength levels for archaic materials and documents the basis for those values as required in § 8-802 .

When historical records may be relied upon

  • Historical records (plans, original drawings, past test reports, documented in-service performance, or records of similar preserved structures) may be used as part of the evaluation per § 8-703.3 when the records are relevant to the structural elements under review .
  • Use historical records to: confirm original material types, previous repairs/alterations, original member sizes, and evidence the structure “withstood the test of time” where no distress is evident (see § 8-705.1) .

When material testing is required or recommended

  • Testing is required or expected when:
    • Assigned strength values would exceed the tabulated/typical CHBC allowances without testing, per § 8-802. The architect/engineer shall not assign greater values than provided in CHBC sections unless supported by adequate testing and the enforcing agency concurs .
    • The material is archaic and its condition or detailing is unclear (the CHBC directs investigation in accordance with § 8-703 and testing "when applicable") .
    • Specific material subsections (for example, masonry, stone, concrete) require representative testing or prescribe when testing is necessary (see § 8-804, § 8-805 and subsections) .
  • Testing should be “representative” (samples from locations that reflect typical construction and condition) and follow recognized procedures (the CHBC references CEBC/IEBC test approaches) .

Decision‑relevant dimensions, thresholds and evidence

Decision item Typical values / threshold Acceptable evidence Code Reference
Who performs evaluation Licensed architect or structural engineer Signed survey, documentation of framing, deterioration, anchors § 8-703.1
Use of historic records Allowed when relevant to evaluated members Original drawings, inspection logs, prior test reports, documented alterations § 8-703.3
Assigning strength without testing Permitted only if within CHBC-provided values or proven by “test of time” and no distress Survey documenting complete load path & no distress; historical load evidence § 8-705.1
When testing needed When assigned values exceed CHBC defaults, or where condition/detailing is unclear Representative lab/site tests; CEBC/IEBC-type procedures § 8-802, § 8-804
Masonry shear guideline (without testing) Maximum ultimate shear = 9 psi (62.1 kPa) for many solid masonry walls (non‑adobe) if conditions met Engineer statement confirming good masonry/mortar and joint fill § 8-805.1
Stone masonry testing Required similar to brick testing when treating as solid masonry; pull tests for non‑interlocked stones Representative pull/shear tests with measured shear area § 8-805.2.3
Concrete/low‑strength materials Strength must be assigned based on testing of samples Core testing, compression tests, bond tests per guidance § 8-808.1

Documentation required

  • A written structural survey and evaluation that documents: materials, dimensions, deterioration, reinforcement, anchorage, load path, and the basis for assigned strengths — historical records and test reports must be attached and referenced in the engineer/architect’s report (see § 8-703.1 and § 8-802) .

Exceptions & special cases

  • Where the CHBC lists a specific allowable value (for example 9 psi ultimate shear for many solid masonry walls), an engineer may use that value without testing if the qualifying inspection conditions are met — otherwise testing is needed (§ 8-805.1) .
  • Archaic materials may be assigned values based on similar conventional codified materials in lieu of tests when a clear, documented equivalence exists — but the architect/engineer must justify the equivalence and the enforcing agency must concur (§ 8-802) .
  • If historical records show no increase in anticipated dead and live loads compared to historical loads and a complete load path is present with no distress, the structure “may be assumed adequate by having withstood the test of time” for gravity loads (see § 8-705.1) .
  • For lateral (seismic) evaluations, CHBC limits on forces apply (e.g., seismic forces need not exceed 0.75 times the regular code forces in some evaluations) — reliance on historical performance does not waive the lateral evaluation requirements in § 8-705.2 / § 8-706 .

Common mistakes

  • Assuming an old building’s survival alone justifies full strength values — survival supports an assessment but the engineer still must document load path, anchorage and absence of distress (don’t skip the survey per § 8-703.1) .
  • Using historic drawings without confirming actual as-built conditions — the CHBC requires verification of details and deterioration; records are a supplement, not a substitute, for the survey (§ 8-703.2 / § 8-703.3) .
  • Assigning strength values higher than CHBC guidance without adequate, representative testing — § 8-802 forbids higher assignments without tests and enforcing‑agency concurrence .
  • Relying on a single, non‑representative test sample — CHBC expects representative testing and documentation in accordance with referenced CEBC/IEBC approaches (§ 8-802, § 8-804) .
  • Forgetting to document reinforcement, anchorage and joint fill — these details directly affect allowable values (see § 8-703.1, § 8-804) .

Worked example — unreinforced brick wall shear capacity

Scenario: A 2-story historic brick building has unreinforced solid brick bearing walls. An owner wants to confirm shear capacity for lateral evaluation.

Step 1 — Survey: The engineer documents wall thickness, unsupported height, mortar condition, presence of complete load path and checks for distress (required by § 8-703.1) .

Step 2 — Use of CHBC default (if qualifying): If inspection shows mortar joints are filled, brick and mortar are “reasonably good,” and the maximum unsupported height-to-thickness ratio does not exceed 13, the CHBC allows a maximum ultimate shear of 9 pounds per square inch (psi) (≈ 62.1 kPa) for such solid masonry without testing§ 8-805.1 .

Concrete numeric application:

  • Wall thickness = 8 in (0.667 ft). Unsupported height = 9 ft → height/thickness = 13.5 → exceeds the CHBC ratio of 13. Because the ratio is slightly over 13, the engineer cannot safely apply the 9 psi default without additional justification or testing.
  • Options: (a) perform representative shear/compression testing per CEBC guidance and assign capacity based on test results; or (b) provide strengthening to reduce unsupported height/length or increase effective thickness so the ratio ≤ 13 and then use 9 psi per § 8-805.1 .

Step 3 — If tests are done, they must be representative and documented; assigned strengths from testing must be presented and are subject to enforcing agency concurrence per § 8-802 .

Related provisions (CHBC)

  • § 8-703.1 — Structural survey scope and who performs it
  • § 8-703.2 — Use of survey results for capacity & design
  • § 8-705.1 — Gravity load evaluation; “test of time” allowance where no distress exists
  • § 8-705.2 — Wind and seismic load evaluation limits and intent
  • § 8-802 — General engineering approaches; assigning strength values and testing requirement
  • § 8-804 — Documentation and evaluation of archaic materials for allowable stresses
  • § 8-805 — Specific allowances and testing guidance for masonry (including the 9 psi guidance)
  • § 8-808.1 — Concrete/low-strength concrete materials: assignment of strength based on testing

Code references

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

  • CHBC § 8-7 High relevance — show source text

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    8-7 STRUCTURAL REGULATIONS

    SECTION 8-701 PURPOSE, INTENT AND SCOPE

    8-701.1 Purpose. The purpose of the CHBC is to provide alternative regulations to the regular code for the structural safety of buildings designated as qualified historical buildings or properties. The CHBC requires enforcing agencies to accept any reasonably equivalent alternatives to the regular code when dealing with qualified historical buildings or properties.

    8-701.2 Intent. The intent of this chapter is to encourage the preservation of qualified historical buildings or structures while providing standards for a minimum level of building performance with the objective of preventing partial or total structural collapse such that the overall risk of life-threatening injury as a result of structural collapse is low.

    8-701.3 Application. The alternative structural regulations provided by Section 8-705 are to be applied in conjunction with the regular code whenever a structural upgrade or reconstruction is undertaken for qualified historical buildings or properties.

    SECTION 8-702 GENERAL

    8-702.1 The CHBC shall not be construed to allow the enforcing agency to approve or permit a lower level of safety of structural design and construction than that which is reasonably equivalent to the regular code provisions in occupancies which are critical to the safety and welfare of the public at large, including, but not limited to, public and private schools, hospitals, municipal police and fire stations and essential services facilities.

    8-702.2 Nothing in these regulations shall prevent voluntary and partial seismic upgrades when it is demonstrated that such upgrades will improve life safety and when a full upgrade would not otherwise be required.

    SECTION 8-703 STRUCTURAL SURVEY

    8-703.1 Scope. When a structure or portion of a structure is to be evaluated for structural capacity under the CHBC, it shall be surveyed for structural conditions by an architect or engineer knowledgeable in historical structures. The survey shall evaluate deterioration or signs of distress. The survey shall determine the details of the structural framing and the system for resistance of gravity and lateral loads. Details, reinforcement and anchorage of structural systems and veneers shall be determined and documented where these members are relied on for seismic lateral resistance.

    8-703.2 The results of the survey shall be utilized for evaluating the structural capacity and for designing modifications to the structural system to reach compliance with this code.

    8-703.3 Historical records. Past historical records of the structure or similar structures may be used in the evaluation, including the effects of subsequent alterations.

    SECTION 8-704 NONHISTORICAL ADDITIONS AND NONHISTORICAL ALTERATIONS

    8-704.1 New nonhistorical additions and nonhistorical alterations which are structurally separated from an existing historical building or structure shall comply with regular code requirements.

    8-704.2 New nonhistorical additions which impose vertical or lateral loads on an existing structure shall not be permitted unless the affected part of the supporting structure is evaluated and strengthened, if necessary, to meet regular code requirements.

    Note: For use of archaic materials, see Chapter 8-8.

    SECTION 8-705 STRUCTURAL REGULATIONS

  • CHBC § 8-702.2 High 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

  • 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 § 8-804 High relevance — show source text

    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. Higher-quality mortar may provide a greater shear value and shall be tested in accordance with Appendix A, Chapter A1 of the California Existing Building Code (CEBC) 2010 edition, and as modified by the CHBC.

    8-805.2 Stone masonry.

    8-805.2.1 Solid-backed stone masonry. Stone masonry solidly backed with brick masonry shall be treated as solid brick masonry as described in Section 8-805.1 and in the 2009 International Existing Building Code [®] (IEBC [®] ), provided representative testing and inspection verifies solid collar joints between stone and brick and that a reasonable number of stones lap with the brick wythes as headers or that steel anchors are present. Solid stone masonry where the wythes of stone effectively overlap to provide the equivalent header courses may also be treated as solid brick masonry.

    8-805.2.2 Independent wythe stone masonry. Stone masonry with independent face wythes may be treated as solid brick masonry as described in Section 8-805.1 and the CEBC, provided representative testing and inspection verify that the core is essentially solid in the masonry wall and that steel ties are epoxied in drilled holes between outer stone wythes at floors, roof and not to exceed 4 feet (1219 mm) on center in each direction, between floors and roof. A reinforcing element shall exist or be provided at or near the top of all stone masonry walls.

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    ARCHAIC MATERIALS AND METHODS OF CONSTRUCTION

    8-805.2.3 Testing of stone masonry. Testing of stone masonry shall be similar to the 2010 CEBC requirements for brick masonry, except that representative stones which are not interlocked shall be pulled outward from the wall and shear area appropriately calculated after the test.

  • California Historical Building Code Medium relevance — show source text

    |100 psf|1 hr
    23 min|||7|1, 2|11/3| |F/C-4-RC-9|4″|4″ deep (4370 psi);1/4″ reinforcement bars
    at 6″ pitch with3/4″ cover;1/4″ main rein-
    forcement bars at 4″ pitch perpendicular
    with1/2″ cover; 13′1″ span restrained.|150 psf|2 hrs|||7|1, 3|2| |F/C-4-RC-10|4″|4″ thick (5140 psi) deck;1/4″ reinforce-
    ment bars at 71/2″ pitch with7/8″ cover;3/8″
    main reinforcement bars at 33/4″ pitch
    perpendicular with1/2″ cover; 13′1″ span
    restrained.|140 psf|1 hr
    16 min|||7|1, 5|11/4| |F/C-4-RC-11|4″|4″ thick (4000 psi) concrete deck;
    3″ × 11/2″ × 4 lbs R.S.J.; 2′6″ C.R.S.; flush
    with top surface; 4″ × 6″ x 13 SWG mesh
    reinforcement 1″ from bottom of slab; 6′6″
    span restrained.|150 psf|2 hrs|||7|1, 3|2| |F/C-4-RC-12|4″|4″ deep (2380 psi) concrete deck;
    3″ × 11/2″ × 4 lbs R.S.J.; 2′6″ C.R.S.; flush
    with top surface; 4″ × 6″ x 13 SWG mesh
    reinforcement 1″ from bottom surface;
    6′6″ span restrained.|150 psf|1 hr
    3 min|||7|1, 2|1| |F/C-4-RC-13|41/2″|41/2″ thick (5200 psi) deck;1/4″ reinforce-
    ment bars at 71/4″ pitch with7/8″ cover;3/8″
    main reinforcement bars at 33/4″ pitch
    perpendicular with1/2″ cover; 13′1″ span
    restrained.|140 psf|2 hrs|||7|1, 3|2| |F/C-4-RC-14|41/2″|41/2″ deep (2525 psi) concrete deck;1/4″
    reinforcement bars at 71/2″ pitch with7/8″
    cover;3/8″ main reinforcement bars at
    33/8″ pitch perpendicular with1/2″ cover;
    13′1″ span restrained.|150 psf|42 min|||7|1, 5|2/3| |F/C-4-RC-15|41/2″|41/2″ deep (4830 psi) concrete deck;
    11/2″ × No.

  • CHBC § 8-706.3 Medium 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 § 1.1.8.1 Medium relevance — show source text

    Upon ratification of_ an adopted ordinance, the city, county, or city and county shall file a copy of the findings of the district, and any findings of the city, county, or city and county, together with the adopted ordinance expressly marked and identified to which each finding refers, in accordance with Section 1.1.8.1(3).

    1.11.2.4 Request for alternate means of protection . Requests for approval to use an alternative material, assembly or materials, equipment, method of construction, method of installation of equipment or means of protection shall be made in writing to the enforcing agency by the owner or the owner’s authorized representative and shall be accompanied by a full statement of the conditions. Sufficient evidence or proof shall be submitted to substantiate any claim that may be made regarding its conformance. The enforcing agency may require tests and the submission of a test report from an approved testing organization as set forth in Title 19, California Code of Regulation, to substantiate the equivalency of the proposed alternative means of protection.

    When a request for alternate means of protection involves hazardous materials, the authority having jurisdiction may consider implementation of the findings and recommendations identified in a Risk Management Plan (RMP) developed in accordance with Title 19, Division 5, Chapter 2, Article 3.

    Approval of a request for use of an alternative material, assembly of materials, equipment, method of construction, method of installation of equipment or means of protection made pursuant to these provisions shall be limited to the particular case covered by request and shall not be construed as establishing any precedent for any future request.

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    ADMINISTRATION

    1.11.2.5 Appeals. When a request for an alternate means of protection has been denied by the enforcing agency, the applicant may file a written appeal to the State Fire Marshal for consideration of the applicant’s proposal. In considering such appeal, the State Fire Marshal may seek the advice of the State Board of Fire Services. The State Fire Marshal shall, after considering all of the facts presented, including any recommendations of the State Board of Fire Services, determine if the proposal is for the purposes intended, at least equivalent to that specified in these regulations in quality, strength, effectiveness, fire resistance, durability and safety, and shall transmit such findings and any recommendations to the applicant and to the enforcing agency.

    1.11.3 Construction documents.

    1.11.3.1 Public schools. Plans and specifications for the construction, alteration or addition to any building owned, leased or rented by any public school district shall be submitted to the Division of the State Architect.

    1.11.3.2 Movable walls and partitions. Plans or diagrams shall be submitted to the enforcing agency for approval before the installation of, or rearrangement of, any movable wall or partition in any occupancy. Approval shall be granted only if there is no increase in the fire hazard.

    1.11.3.3 New construction high-rise buildings. 1. Complete plans or specifications, or both, shall be prepared covering all work required to comply with new construction high-rise buildings. Such plans and specifications shall be submitted to the enforcing agency having jurisdiction. 2. All plans and specifications shall be prepared under the responsible charge of an architect or a civil or structural engineer _authorized by law to develop construction plans and specifications, or by both such architect and engineer.

  • California Historical Building Code Medium relevance — show source text

    3/8″
    main reinforcement bars at 57/8″ pitch
    with7/8″ concrete cover;3/8″ main rein-
    forcement bars at 41/2″ pitch
    perpendicular with1/2″ concrete cover;
    13′1″ span restrained.|195 psf|4 hrs|||7|1, 7|4| |F/C-4-RC-7|4″|4″ (5025 psi) concrete deck;1/4″ reinforce-
    ment bars at 71/2″ pitch with3/4″ cover;3/8″
    main reinforcement bars at 33/4″ pitch
    perpendicular with1/2″ cover; 13′1″ span
    restrained.|140 psf|1 hr
    16 min|||7|1, 2|11/4| |F/C-4-RC-8|4″|4″ thick (4905 psi) deck;1/4″ reinforce-
    ment bars at 71/2″ pitch with7/8″ cover;3/8″
    main reinforcement bars at 33/4″ pitch
    perpendicular with1/2″ cover; 13′1″ span
    restrained.|100 psf|1 hr
    23 min|||7|1, 2|11/3| |F/C-4-RC-9|4″|4″ deep (4370 psi);1/4″ reinforcement bars
    at 6″ pitch with3/4″ cover;1/4″ main rein-
    forcement bars at 4″ pitch perpendicular
    with1/2″ cover; 13′1″ span restrained.|150 psf|2 hrs|||7|1, 3|2| |F/C-4-RC-10|4″|4″ thick (5140 psi) deck;1/4″ reinforce-
    ment bars at 71/2″ pitch with7/8″ cover;3/8″
    main reinforcement bars at 33/4″ pitch
    perpendicular with1/2″ cover; 13′1″ span
    restrained.|140 psf|1 hr
    16 min|||7|1, 5|11/4| |F/C-4-RC-11|4″|4″ thick (4000 psi) concrete deck;
    3″ × 11/2″ × 4 lbs R.S.J.; 2′6″ C.R.S.; flush
    with top surface; 4″ × 6″ x 13 SWG mesh
    reinforcement 1″ from bottom of slab; 6′6″
    span restrained.|150 psf|2 hrs|||7|1, 3|2| |F/C-4-RC-12|4″|4″ deep (2380 psi) concrete deck;
    3″ × 11/2″ × 4 lbs R.S.J.; 2′6″ C.R.S.

  • CHBC § 8-807.3 Medium relevance — show source text

    8-807.3 Existing wood framing. Existing wood framing members may be assigned allowable stresses consistent with codes in effect at the time of construction. Existing or new replacement wood framing may be of archaic types originally used if properly researched, such as balloon and single wall. Wood joints such as dovetail and mortise and tenon types may be used structurally, provided they are well made. Lumber selected for use and type need not bear grade marks, and greater or lesser species such as low-level pine and fir, boxwood and indigenous hardwoods and other variations may be used for specific conditions where they were or would have been used.

    Wood fasteners such as square or cut nails may be used with a maximum increase of 50 percent over wire nails for shear.

    SECTION 8-808 CONCRETE

    8-808.1 Materials. Natural cement concrete, unreinforced rubble concrete and similar materials may be utilized wherever that material is used historically. Concrete of low strength and with less reinforcement than required by the regular code may remain in place. The architect or engineer shall assign appropriate values of strength based on testing of samples of the materials. Bond and development lengths shall be determined based on historical information or tests.

    8-808.2 Detailing. The architect or engineer shall carefully evaluate all detailing provisions of the regular code which are not met and shall consider the implications of these variations on the ultimate performance of the structure, giving due consideration to ductility and reserve strength.

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    ARCHAIC MATERIALS AND METHODS OF CONSTRUCTION

    SECTION 8-809 STEEL AND IRON

    The hand-built, untested use of wrought or black iron, the use of cast iron or grey iron, and the myriad of joining methods that are not specifically allowed by code may be used wherever applicable and wherever they have proven their worth under the considerable span of years involved with most qualified historical buildings or structures. Uplift capacity should be evaluated and strengthened where necessary. Fixed conditions or midheight lateral loads on cast iron columns that could cause failure should be taken into account. Existing structural wrought, forged steel or grey iron may be assigned the maximum working stress prevalent at the time of original construction.

    SECTION 8-810 HOLLOW CLAY TILE

    The historical performance of hollow clay tile in past earthquakes shall be carefully considered in evaluating walls of hollow clay tile construction. Hollow clay tile bearing walls shall be evaluated and strengthened as appropriate for lateral loads and their ability to maintain support of gravity loads. Suitable protective measures shall be provided to prevent blockage of exit stairways, stairway enclosures, exit ways and public ways as a result of an earthquake.

    SECTION 8-811 VENEERS

    8-811.1 Terra cotta and stone. Terra cotta, cast stone and natural stone veneers shall be investigated for the presence of suitable anchorage. Steel anchors shall be investigated for deterioration or corrosion. New or supplemental anchorage shall be provided as appropriate.

    8-811.2 Anchorage. Brick veneer with mechanical anchorage at spacings greater than required by the regular code may remain, provided the anchorages have not corroded. Nail strength in withdrawal in wood sheathing may be utilized to its capacity in accordance with code values.

    SECTION 8-812 GLASS AND GLAZING

  • CHBC § 8-705.1 Medium relevance — show source text

    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

    SECTION 8-706 LATERAL LOAD REGULATIONS

    8-706.1 Seismic forces. Strength-level seismic forces used to evaluate the structure for resistance to seismic loads shall be based on the R -values tabulated in the regular code for similar lateral-force-resisting systems including consideration of the structural detailing of the members where such R -values exist. Where such R -values do not exist, an appropriate R -value shall be rationally assigned considering the structural detailing of the members.

    Exceptions:

    1. The forces need not exceed 0.75 times the seismic forces prescribed by the regular code requirements.
    2. For Risk Category I, II or III structures, near-fault increases in ground motion (maximum considered earthquake ground motion of 0.2 second spectral response greater than 150 percent at 5 percent damping) need not be considered when the fundamental period of the building is 0.5 seconds in the direction under consideration.
    3. For Risk Category I or II structures, the seismic base shear need not exceed 0.30W.
    4. For Risk Category III or IV structures, the seismic base shear need not exceed 0.40W.

    8-706.1.1 When a building is to be strengthened with the addition of a new lateral force resisting system, the R -value of the new system can be used when the new lateral force resisting system resists at least 75 percent of the building’s base shear regardless of its relative rigidity.

    8-706.1.2 Evaluation and seismic improvement of unreinforced masonry bearing wall buildings shall comply with the California Existing Building Code (CEBC), Appendix Chapter A1 2013 Edition, and as modified by the CHBC.

    Exceptions:

  • 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 § 653-5791 Medium relevance — show source text

    Option 5 > Option 2 State Housing Law: including Housing Accessibility, Hotels/Motels, Apartments/Condominiums, Dormitories, Single-Family Dwellings, ADUs, Permanent Structures in Mobile Home Parks

    Option 5 > Option 4 Factory-Built Housing Option 5 > Option 5 Employee Housing

    Department of Water Resources [DWR]

    water.ca.gov DWRwebcomment@water.ca.gov

    (916) 653-5791 Plumbing for Recycled Water, Floodplain Construction

    Division of the State Architect

    dgs.ca.gov/DSA (916) 445-8100

    Access Compliance DSAAC 445-5827 DSAaccess@dgs.ca.gov Access for Persons with Disabilities

    Structural Safety [DSA-SS, DSA-SS/CC]

    Public Schools & Community Colleges, State Essential Services Buildings

    State Historical Building Safety Board [SHBSB] (916) 445-7627 shbsb@dgs.ca.gov

    Historical Building Rehabilitation, Preservation, Restoration or Relocation

    Energy Commission [CEC]

    energy.ca.gov Title24@energy.ca.gov (800) 772-3300 Building Energy Efficiency, Compliance Manual & Compliance Forms

    Office of the State Fire Marshal [SFM]

    osfm.fire.ca.gov codedevelopment@fire.ca.gov

    (916) 568-3800 Fire & Life Safety

    State Lands Commission [SLC]

    slc.ca.gov MOTEMS.Public@slc.ca.gov (510) 741-4950 Marine Oil Terminals

    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.

Frequently asked questions

When can I rely only on historic drawings to size members?

Historic drawings may be used, but the CHBC requires a current structural survey by a qualified architect/engineer to verify as‑built conditions and deterioration before assigning capacity (see § 8-703.1–.3) .

Is testing always required to use higher strength values than CHBC defaults?

Yes — § 8-802 requires adequate testing (and enforcing‑agency concurrence) before assigning values greater than CHBC‑provided values .

How many samples do I need for representative testing?

The CHBC requires “representative testing” but does not prescribe a single sample count; sampling must be sufficient to represent typical construction and condition and follow CEBC/IEBC guidance referenced in the CHBC (§ 8-802, § 8-804) .

Can an untested archaic material remain in place?

Yes, but allowable stresses must be assigned conservatively based on similar conventional materials or historical performance, and the architect/engineer must document the basis as required in § 8-802 and § 8-804 .

Who approves the use of records or test-based strengths?

The architect/engineer prepares and signs the evaluation; assigned values above CHBC defaults require the enforcing agency’s concurrence per § 8-802 .

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