CBC · California Building Code

What exceptions, thresholds or limited-scope options exist (assessment vs retrofit)?

If your state‑owned building project meets triggers in § 317.3.1 (for example cumulative construction cost >25% of replacement cost, damage or >10% change in seismic demand), you must have a § 317 seismic evaluation and may need to retrofit. If those triggers are not met, § 317.11 allows voluntary, limited seismic improvements under § 319.12 (with required engineering analysis and documentation).

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Last reviewed: July 5, 2026

What the code requires

For existing state‑owned buildings the CBC requires a seismic evaluation and, if the evaluation shows performance below the Chapter 317 performance objectives, a retrofit—unless the project falls outside the applicability triggers in § 317.3.1 (in which case only limited requirements apply). See § 317.3.1 for the applicability triggers and the cross‑reference to § 317.11 for cases where only voluntary or limited modifications are allowed.

Requirements in detail

Applicability triggers (when an assessment and potential retrofit are required)

Section 317 establishes when a design professional must evaluate seismic performance and when retrofit is required. For existing state‑owned buildings, § 317.3.1 lists the specific thresholds and conditions that cause Section 317’s evaluation/retrofit requirements to apply; if none of those triggers are met, the work may be governed only by the limited/voluntary provisions (§ 317.11 / § 319.12).

Decision‑relevant dimensions (summary table)

Decision dimension	Threshold / value	Effect (assessment vs retrofit)	Code reference
Total construction cost of project (state‑owned)	Exceeds 25% of replacement cost (excluding FF&E/maintenance)	Triggers Section 317 evaluation/retrofit requirements	§ 317.3.1
Change in seismic forces or strength requirement on a component	Increases > 10% cumulative since original construction	Triggers Section 317 applicability (evaluation/retrofit)	§ 317.3.1(3)
Damage to lateral system	Lateral‑load capacity reduced > 10%	Triggers Section 317 applicability (evaluation/retrofit)	§ 317.3.1(4)
Change in live or dead load	Story shear increases > 10%	Triggers Section 317 applicability (evaluation/retrofit)	§ 317.3.1(5)
Additions floor area exception for seismic hazard table	Addition > larger of 50% of original floor area or 1,000 sq ft	Replaces certain Table 317.5 seismic hazard entries (more stringent design basis)	§ 317.5 exception
Projects that do not meet § 317.3 applicability	—	If § 317.3 determines assessment is not required, only the limited provisions (§ 317.11 / § 319.12) apply	§ 317.2 Exception; § 317.11

What “assessment” means under § 317 (brief)

If a project meets any § 317.3 triggers, the registered design professional must provide a seismic evaluation per § 317.4. If that evaluation shows the building meets the performance levels in § 317.5 (and the peer reviewer concurs where required), then no retrofit is required. If it does not meet the performance objectives, retrofit is required (§ 317.6).

Limited‑scope / voluntary options (§ 317.11 and § 319.12)

When the exception in § 317.2 applies (i.e., assessment is not required per § 317.3 or retrofit is not required per § 317.4), § 317.11 allows voluntary modifications to the lateral force resisting system under the requirements of § 319.12. Section 319.12 permits voluntary strengthening provided several conditions are met (for example: existing component capacity is not reduced; lateral loading to existing components is not increased beyond capacity; connections and detailing follow CBC/ASCE guidance; no dangerous condition is created). Use of ASCE 41 Tier 1 and Tier 2 deficiency‑only procedures is pre‑approved where § 317.3 does not require an assessment.

Exceptions & special cases

§ 317.2 Exception: If § 317.3 determines assessment is not required (i.e., none of the triggers in § 317.3.1–.3.3 apply) or § 317.4 determines retrofit is not needed, then only § 317.11 (voluntary modifications) applies. This explicitly limits the scope to voluntary/limited work rather than a full retrofit.
Voluntary modifications: § 317.11 refers users to § 319.12 for voluntary work. § 319.12 requires that voluntary work not reduce capacity, not increase demands beyond existing capacity, and ensure connectors/details meet CBC requirements; the designer must document the scope and acceptance criteria.
Pre‑approved streamlined procedures: For projects where § 317.3 does not require an assessment, ASCE 41 Tier 1 and Tier 2 deficiency‑only procedures are explicitly allowed without additional acceptance. That permits a limited, prescriptive approach for voluntary improvements.
Public schools / community colleges: The provisions apply to these institutions when required by the California Administrative Code; separate DSA rules may alter applicability. See § 317.1.2 / § 317.1.3 for references.

Common mistakes

Treating voluntary work as a full retrofit: Designers sometimes assume that voluntary strengthening avoids all documentation—but § 319.12 requires explicit engineering analysis and clear scope/acceptance criteria when voluntary methods are used. § 317.11 simply permits voluntary work under § 319.12; it does not remove documentation requirements.
Ignoring cumulative past work: The 25% cost threshold in § 317.3.1 is cumulative for modifications after the 1995 CBC that did not require seismic retrofit—so partial prior projects can push a current project over the threshold. Evaluate cumulative costs, not only the current project cost.
Misapplying the 10% rule: The “more than 10%” triggers for increased seismic forces, decreased capacity or load changes are cumulative since original construction—do not apply them as single isolated checks without accounting for prior changes. § 317.3.1 items (3)–(5) specify the >10% criteria.
Assuming voluntary = simple: Even where only § 317.11 applies, § 319.12 demands that the capacity of existing components not be reduced (unless shown acceptable), connections be detailed to CBC standards, and that no dangerous condition be created.

Worked example — concrete scenario

Scenario: A state‑owned administrative building (replacement cost $10,000,000) will undergo an interior remodel with structural work. The owner’s estimated construction cost (excluding furniture, fixtures and equipment) for the current project is $2,600,000. During records review the structural engineer finds past non‑seismic upgrades after 1995 totaling $500,000.

Step 1 — Does § 317.3.1 apply?

Calculate cumulative recent modification cost: $2,600,000 (current) + $500,000 (past modifications) = $3,100,000.
Replacement cost = $10,000,000. Threshold = 25% × $10,000,000 = $2,500,000.
Cumulative modifications ($3,100,000) exceed 25% → § 317.3.1(1) is met → Section 317 evaluation applies. Cite: § 317.3.1.

Step 2 — Evaluation and outcome

The registered design professional performs the § 317 evaluation per § 317.4. If the building meets the § 317.5 performance objectives, no retrofit is required. If it does not, retrofit per § 317.6 is required. Documentation and possible peer review are required under Methods A or B (Sections 320–321 and peer review in § 322 as applicable).

Alternative outcome (limited scope): If cumulative modifications had been $2,400,000 (below the 25% threshold) and no other § 317.3.1 triggers applied (no >10% force changes, no >10% damage, no risk‑category change), then assessment under § 317 might not be required and voluntary strengthening could proceed under § 317.11 / § 319.12 using ASCE 41 Tier‑1/2 deficiency procedures where pre‑approved.

Related provisions

§ 317.2 — Scope and exception tying assessment requirement to § 317.3 (see cross‑reference to § 317.11).
§ 317.3.1 — Applicability triggers for existing state‑owned buildings (cost, risk category, >10% component changes, damage, loads).
§ 317.4 — Evaluation required when § 317.3 triggers apply; evaluation procedure and outcomes (satisfactory → no retrofit).
§ 317.5 — Minimum seismic performance levels and the Table 317.5 exceptions for additions.
§ 317.6 — Retrofit required where evaluation indicates building does not meet required performance.
§ 317.11 — Voluntary lateral‑force‑resisting system modifications; point to § 319.12 for requirements.
§ 319.12 — Conditions, documentation and limitations for voluntary lateral‑force‑resisting system modifications.
Sections 320–321 — Approved analysis/compliance methods (Method A / Method B) and peer review requirements (see § 321 and § 322).

Code references

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

CBC § 317.1.2.1 High relevance — show source text
The provisions of Section 317 through 323 also establish minimum standards for earthquake evaluation and design for rehabilitation of existing public buildings currently under the jurisdiction of DSA-SS.

317.1.2.1 Reference to other chapters. For public schools, where reference within this chapter is made to sections in Chapters 16, 17, 18, 19, 21 or 22 of the California Building Code, the provisions in Chapters 16A, 17A, 18A, 19A, 21A and 22A of the California Building Code, respectively, shall apply instead.

317.1.3 Community college buildings. [DSA-SS/CC] The provisions of Sections 317 through 323 establish minimum standards for earthquake evaluation and design for the rehabilitation of existing buildings for use as community college buildings under the jurisdiction of the Division of the State Architect—Structural Safety/Community Colleges [DSA-SS/CC], refer to Section 1.9.2.2.

The provisions of Section 317 through 323 also establish minimum standards for earthquake evaluation and design for rehabilitation of existing community college buildings currently under the jurisdiction of DSA-SS/CC.

317.1.3.1 Reference to other chapters. For community colleges, where reference within this chapter is made to sections in Chapters 17 or 18 of the California Building Code, the provisions in Chapters 17A and 18A of the California Building Code, respectively, shall apply instead.

317.2 Scope. All alterations, structurally connected additions and/or repairs to existing structures or portions thereof shall, at a minimum, be designed and constructed to resist the effects of seismic ground motions as provided in this section. The structural system shall be evaluated by a registered design professional and, if not meeting or exceeding the minimum seismic design performance requirements of this section, shall be retrofitted in compliance with these requirements.

Exception: Those structures for which Section 317.3 determines that assessment is not required, or for which Section 317.4 determines that retrofit is not needed, then only the requirements of Section 317.11 apply.

317.3 Applicability.

317.3.1 Existing state-owned buildings. [BSC, DSA-SS] For existing state-owned structures including all buildings owned by the University of California and the California State University, the requirements of Section 317 apply whenever the structure is to be retrofitted, repaired or modified and any of the following apply: 1. Total construction cost, not including cost of furnishings, fixtures and equipment, or normal maintenance, for the building exceeds 25 percent of the construction cost for the replacement of the existing building. The changes are cumulative for past modifications to the building that occurred after adoption of the 1995 California Building Code and did not require seismic retrofit.

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PROVISIONS FOR ALL COMPLIANCE METHODS
CBC § 317.2 High relevance — show source text
317.2 Scope. All alterations, structurally connected additions and/or repairs to existing structures or portions thereof shall, at a minimum, be designed and constructed to resist the effects of seismic ground motions as provided in this section. The structural system shall be evaluated by a registered design professional and, if not meeting or exceeding the minimum seismic design performance requirements of this section, shall be retrofitted in compliance with these requirements.

Exception: Those structures for which Section 317.3 determines that assessment is not required, or for which Section 317.4 determines that retrofit is not needed, then only the requirements of Section 317.11 apply.

317.3 Applicability.

317.3.1 Existing state-owned buildings. [BSC, DSA-SS] For existing state-owned structures including all buildings owned by the University of California and the California State University, the requirements of Section 317 apply whenever the structure is to be retrofitted, repaired or modified and any of the following apply: 1. Total construction cost, not including cost of furnishings, fixtures and equipment, or normal maintenance, for the building exceeds 25 percent of the construction cost for the replacement of the existing building. The changes are cumulative for past modifications to the building that occurred after adoption of the 1995 California Building Code and did not require seismic retrofit.

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2. There are changes in risk category. 3. The modification to the structural components increases the seismic forces in or strength requirements of any structural component of the existing structure by more than 10 percent cumulative since the original construction, unless the component has the capacity to resist the increased forces determined in accordance with Section 319. If the building’s seismic base shear capacity has been increased since the original construction, the percent change in base shear may be calculated relative to the increased value.

4. Structural elements need repair where the damage has reduced the lateral-load-resisting capacity of the structural system by more than 10 percent. 5. Changes in live or dead load increase story shear by more than 10 percent.

317.3.2 Public school buildings. [DSA-SS] For public schools, the provisions of Section 317 apply when required in accordance with Sections 4-307 and 4-309(c) of the California Administrative Code.

317.3.3 Community college buildings. [DSA-SS/CC] For community colleges, the provisions of Section 317 apply when required in accordance with Sections 4-307 and 4-309(c) of the California Administrative Code.

317.4 Evaluation required. If the criteria in Section 317.3 apply to the project under consideration, the design professional of record shall provide an evaluation in accordance with Section 317 to determine the seismic performance of the building in its current configuration and condition. If the structure's seismic performance as required by Section 317.5 is evaluated as satisfactory and the peer reviewer(s), when Method B of Section 321 is used, concur, then no structural retrofit is required.

_**317.5 Minimum seismic design performance levels for structural and nonstructural components.
CBC § 301.1 High relevance — show source text
SECTION 301—ADMINISTRATION

301.1 Applicability. The repair, alteration, change of occupancy, addition or relocation of all existing buildings shall comply with Section 301.2, 301.3 or 301.4. The provisions of Sections 302 through 309 shall apply to all alterations, repairs, additions, relocation of structures and changes of occupancy regardless of compliance method. [OSHPD 1R, 2, 4 and 5] Section 301.4 not permitted by OSHPD.

Exceptions: 1. Existing state-owned structures. [BSC] The repair, alteration, change of occupancy, addition or relocation of all existing buildings shall comply with the provisions of Sections 317 through 322 as the minimum standards for earthquake evaluation and design for retrofit of existing state-owned structures, including buildings owned by the University of California, the California State University or the Judicial Council. The provisions of Sections 317 through 322 may be adopted by a local jurisdiction for earthquake evaluation and design for retrofit of existing buildings. 2. Public school buildings [DSA-SS] The provisions of Sections 317 through 323 establish minimum standards for earthquake evaluation and design for the rehabilitation of existing buildings for use as public school buildings under the jurisdiction of the Division of the State Architect—Structural Safety (DSA-SS, refer to Section 1.9.2.1) where required by Sections 4-307 and 4-309(c) of the California Administrative Code. The provisions of Sections 317 through 323 also establish minimum standards for earthquake evaluation and design for rehabilitation of existing public school buildings currently under the jurisdiction of DSA-SS. 3. Community college buildings. [DSA-SS/CC] The provisions of Sections 317 through 323 establish minimum standards for earthquake evaluation and design for the rehabilitation of existing buildings for use as community college buildings under the jurisdiction of the Division of the State Architect—Structural Safety/Community Colleges (DSA-SS/CC, refer to Section 1.9.2.2) where required by Sections 4-307 and 4-309(c) of the California Administrative Code. The provisions of Sections 317 through 323 also establish minimum standards for earthquake evaluation and design for rehabilitation of existing community college buildings currently under the jurisdiction of DSA-SS/CC. 4. [HCD 1] In addition to the requirements in this chapter, maintenance, alteration, repair, addition or change of occupancy to existing buildings and accessory structures under the authority of the Department of Housing and Community Development, as provided in Section 1.8.2.1.1, shall comply with California Code of Regulations, Title 25, Division 1, Chapter 1, Subchapter 1.

Exceptions: 1. [HCD 2] For moved buildings and maintenance, alteration, repair, addition or change of occupancy to existing buildings and accessory structures in mobilehome parks or special occupancy parks as provided in Section 1.8.2.1.3, see California Code of Regulations, Title 25, Division 1, Chapters 2 and 2.2. 2. [HCD 1] Limited-density owner-built rural dwellings, as defined in Chapter 2 of the California Residential Code. _**5.
CBC § 309.2.1 High relevance — show source text
2||||X|X|||||||||||||||||||| |309.2.1|||X|||||||||||||||||||||| |310 – 311|||||||||||X|X|||X|||||||||| |312|||||||||||X|||||||||||||| |313 – 316|||X|||||||||||||||||||||| |317 – 322|X|||||||X|X|||||||||||||||| |323||||||||X|X||||||||||||||||

The state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.

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User notes:

About this chapter: Chapter 3 explains the three compliance options for alterations and additions available in the code. In addition, this chapter also lays out the methods to be used for seismic design and evaluation throughout this code. Finally, this chapter clarifies that provisions in other I-Codes related to repairs, alterations, additions, relocation and changes of occupancy must also be addressed unless they conflict with this code. In that case, this code takes precedence.

SECTION 301—ADMINISTRATION

301.1 Applicability. The repair, alteration, change of occupancy, addition or relocation of all existing buildings shall comply with Section 301.2, 301.3 or 301.4. The provisions of Sections 302 through 309 shall apply to all alterations, repairs, additions, relocation of structures and changes of occupancy regardless of compliance method. [OSHPD 1R, 2, 4 and 5] Section 301.4 not permitted by OSHPD.

Exceptions: 1. Existing state-owned structures. [BSC] The repair, alteration, change of occupancy, addition or relocation of all existing buildings shall comply with the provisions of Sections 317 through 322 as the minimum standards for earthquake evaluation and design for retrofit of existing state-owned structures, including buildings owned by the University of California, the California State University or the Judicial Council. The provisions of Sections 317 through 322 may be adopted by a local jurisdiction for earthquake evaluation and design for retrofit of existing buildings. 2. Public school buildings [DSA-SS] The provisions of Sections 317 through 323 establish minimum standards for earthquake evaluation and design for the rehabilitation of existing buildings for use as public school buildings under the jurisdiction of the Division of the State Architect—Structural Safety (DSA-SS, refer to Section 1.9.2.1) where required by Sections 4-307 and 4-309(c) of the California Administrative Code. The provisions of Sections 317 through 323 also establish minimum standards for earthquake evaluation and design for rehabilitation of existing public school buildings currently under the jurisdiction of DSA-SS. 3. _**Community college buildings.

CBC § 1.11. High relevance — show source text

Adopting Agency	BSC	BSC- CG	SFM	HCD	Col6	Col7	DSA	Col9	Col10	OSHPD	Col12	Col13	Col14	Col15	Col16	Col17	BSCC	DPH	AGR	DWR	CEC	CA	SL	SLC
Adopting Agency	BSC	BSC- CG	SFM	1	2	1/AC	AC	SS	SS/CC	1	1R	2	3	4	5	6	6	6	6	6	6	6	6	6
Adopt Entire Chapter
Adopt Entire Chapter as amended (amended sections listed below)
Adopt only those sections that are listed below
Chapter / Section

The state agency does not adopt sections identified with the following symbol: † The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.

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APPENDIX C—GUIDELINES FOR THE WIND RETROFIT OF EXISTING BUILDINGS

CHAPTER C2 ROOF DECK FASTENING FOR HIGH-WIND AREAS

SECTION C201—GENERAL

[BS] C201.1 Purpose. This chapter provides prescriptive methods for partial structural retrofit of an existing building to increase its resistance to wind loads. It is intended for voluntary use where the basic wind speed, V, is greater than 130 mph (58 m/s) in accordance with Figure 1609.3(2) of the California Building Code and for reference by mitigation programs. The provisions of this chapter do not necessarily satisfy requirements for new construction. Unless specifically cited, the provisions of this chapter do not necessarily satisfy requirements for structural improvements triggered by addition, alteration, repair, change of occupancy, building relocation or other circumstances.

[BS] C201.2 Eligible conditions. The provisions of this chapter are applicable only to buildings that meet either of the following eligibility requirements:

Buildings assigned to Risk Category I or II in accordance with Table 1604.5 of the California Building Code .
Buildings within the scope of the California Residential Code .

SECTION C202—ROOF DECK ATTACHMENT FOR WOOD ROOFS

CBC § 0.91 High relevance — show source text
Fourth, fifth_
and sixth floors and the second and third basement floor level quantity shall be reduced to 75 percent of this table. The seventh through 10th floor and below the third basement
floor level quantity shall be reduced to 50 percent of this table.
2. Permitted only when stored or used in approved exhausted gas cabinets, exhausted enclosures or fume hoods. Quantities of high toxics in use in open systems need not be reduced
above the third floor or below the first basement floor level. Individual container size shall be limited to 2 pounds (0.91 kg) for solids and1/4 gallon (0.95 L) for liquids.|

SECTION 317 [BSC, DSA-SS & DSA-SS/CC]—EARTHQUAKE EVALUATION AND DESIGN FOR RETROFIT OF EXISTING BUILDINGS

317.1 Purpose.

317.1.1 Existing state-owned structures. [BSC] The provisions of Sections 317 through 322 establish minimum standards for earthquake evaluation and design for retrofit of existing state-owned structures, including buildings owned by the University of California and the California State University.

The provisions of Sections 317 through 323 may be adopted by a local jurisdiction for earthquake evaluation and design for retrofit of existing buildings.

317.1.2 Public school buildings. [DSA-SS] The provisions of Sections 317 through 323 establish minimum standards for earthquake evaluation and design for the rehabilitation of existing buildings for use as public school buildings under the jurisdiction of the Division of the State Architect—Structural Safety [DSA-SS], refer to Section 1.9.2.1.

The provisions of Section 317 through 323 also establish minimum standards for earthquake evaluation and design for rehabilitation of existing public buildings currently under the jurisdiction of DSA-SS.

317.1.2.1 Reference to other chapters. For public schools, where reference within this chapter is made to sections in Chapters 16, 17, 18, 19, 21 or 22 of the California Building Code, the provisions in Chapters 16A, 17A, 18A, 19A, 21A and 22A of the California Building Code, respectively, shall apply instead.

317.1.3 Community college buildings. [DSA-SS/CC] The provisions of Sections 317 through 323 establish minimum standards for earthquake evaluation and design for the rehabilitation of existing buildings for use as community college buildings under the jurisdiction of the Division of the State Architect—Structural Safety/Community Colleges [DSA-SS/CC], refer to Section 1.9.2.2.

The provisions of Section 317 through 323 also establish minimum standards for earthquake evaluation and design for rehabilitation of existing community college buildings currently under the jurisdiction of DSA-SS/CC.

317.1.3.1 Reference to other chapters. For community colleges, where reference within this chapter is made to sections in Chapters 17 or 18 of the California Building Code, the provisions in Chapters 17A and 18A of the California Building Code, respectively, shall apply instead.
CBC § 0.30 High relevance — show source text
1. Guards per Section 1013 if a rooftop platform is provided; or

2. A railing that is 12 inches (305 mm) in height if a sloped roof is provided.

K107.6 Utility/equipment buffer zone. A separation of 48 inches shall be provided between a rooftop evacuation location and any mechanical equipment, photovoltaic system, utility service drop or other utility line. Electrical service lines shall not pass over evacua- tion locations.

SECTION K108 — ATTICS THAT ARE EVACUATION LOCATIONS

K108.1 General. Attics that have finish floors no less than one (1) foot (0.30 meter) above the WSEL200 shall be permitted to be evacua- tion locations.

K108.2 Headroom. When an attic is used as an evacuation location, the minimum headroom of the required area shall be 30 inches (762 mm) with 50 percent of the required area having a headroom of 60 inches (1524 mm).

K108.3 Attic flooring. The required area of the evacuation location shall be solidly sheathed.

K108.4 Attic live loads. Attic areas that are used as evacuation locations shall be designed for the floor live load required for the occu- pancy as required in Table 1607.2.

K108.5 Evacuation routes to attic evacuation locations. Evacuation routes to attic evacuation locations shall be permitted to be provided by a stairway, ramp, alternating tread device, fixed ladder or other means approved by the building official.

Exception: In Group R-3.1 occupancies that are subject to the requirements of Chapter 11A or 11B, such requirements shall apply to the evacuation routes to attics.

K108.6 Means of escape from attics. The means of escape from attics shall comply with Section K105.

SECTION K109 — ALTERNATE MEANS OF PROTECTION

K109.1 Request for approval of alternate means of protection. Requests for approval to use an alternative means of protection shall be made in writing to the building official by the owner or the owner’s authorized representative. The request shall be accompanied by a full statement of the conditions and sufficient evidence that the proposed alternate means of protection provides reasonable protection to occupants. The building official shall require the owner to obtain a written statement from the applicable emergency management authority regarding plans and processes related to notification of anticipated conditions of flooding, warnings, evacuations and other pertinent conditions relative to the proximity of nearby levees. The building official shall also require the owner to obtain a written state- ment and findings from the entity that has jurisdiction over the management, maintenance, monitoring and control of flood protection works in the vicinity of the location of the owner’s property; such statement shall comment on the viability of the proposed alternate means of protection. The building official may request written statements from the Central Valley Flood Protection Board, the California Department of Water Resources, and the California Emergency Management Agency.

Approval of a request for use of an alternative means of protection made pursuant to these provisions shall be limited to the particu- lar case covered by the request and shall not be construed as establishing any precedent for any future request except in substantially equivalent situations.
CBC § 505.2 High relevance — show source text
20|||X|||||||||||||||||||||| |504|||X|†|†|†|||||X|X||X|X|||||||||| |505|||X||||||||X|X||X|X|||||||||| |505.2||||X|X|||||||||||||||||||| |506|||||||||||X|X||X|X|||||||||| |506.1 –506.1.1|X||X|||||||||||||||||||||| |506.1.2|||||||||||X|X||X|X|||||||||| |506.2 – 506.3|X||X|||||||||||||||||||||| |506.4|||X|||||||||||||||||||||| |506.5_ Exception_|X|||||||||||||||||||||||| |506.6||||†|†|†|||||||||||||||||||

The state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.

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5 PRESCRIPTIVE COMPLIANCE METHOD

User notes:

About this chapter: Chapter 5 provides details for the prescriptive compliance method—one of the three main options of compliance available in this code for buildings and structures undergoing alteration, addition or change of occupancy.

SECTION 501—GENERAL

501.1 Scope. The provisions of this chapter shall control the alteration, addition and change of occupancy of existing buildings and structures, including historic buildings and structures, [BSC] including state-regulated structures in accordance with Section 501.1.2. Historic buildings and structures shall comply with Part 8, Title 24, C.C.R.

Exceptions: 1. [HCD 2] For relocated or moved buildings and maintenance, alteration, repair, addition or change of occupancy to existing buildings and accessory structures in mobilehome parks or special occupancy parks as provided in Section 1.8.2.1.3. See California Code of Regulations, Title 25, Division 1, Chapters 2 and 2.2. 2. [HCD 1] Limited-density owner-built rural dwellings.

[HCD 1] In addition to the requirements in this chapter, maintenance, alteration, repair, addition or change of occupancy to existing buildings and accessory structures under the authority of the Department of Housing and Community Development, as provided in Section 1.8.2.1.1, shall comply with California Code of Regulations, Title 25, Division 1, Chapter 1, Subchapter 1.

501.1.1 Compliance with other methods. Alterations, additions and changes of occupancy to existing buildings and structures shall comply with the provisions of this chapter or with one of the methods provided in Section 301.3.

501.1.2 Existing state-owned structures. [BSC] The provisions of Sections 317 through 322 establish minimum standards for earth- quake evaluation and design for retrofit of existing state-owned structures, including buildings owned by the University of California, the California State University and the Judicial Council.
CBC § 3.3.44.2 High relevance — show source text
Amend Section 3.3.44.2 and amend publications to read as follows:

3.3.44.2 Open Station.* A station that is constructed such that it is directly open to the atmosphere and smoke and heat are allowed to disperse directly into the atmosphere.

The following enclosed areas in open stations are permitted:

1. Ticket/pass booths not exceeding 150 square feet (13.9 m [2] ) in area. 2. Mechanical and electrical spaces typically not used for human occupancy and necessary for the operation of a fixed guideway transit system. Such spaces shall be limited to two per level. 3. Restrooms not exceeding 150 square feet (13.9 m [2] ) in area. A maximum of four restrooms are permitted per level.

Add a new definition as 3.3.44.3 to read as follows:

3.3.44.1.1 Underground Station. A station or portion thereof that is located beneath the surface of the earth or of the water.

Amend Section 5.2.2.1 to read as follows:

5.2.2.1 Building construction for all new enclosed stations shall be not less than Type IA, Type IB or Type IIA construction and shall not exceed in area or height the limits specified in the California Building Code Table 503, for the station configuration or as determined by fire hazard analysis of potential fire exposure hazards to the structure.

Add Section 5.2.2.1.1 –5.2.2.1.3 to read as follows:

5.2.2.1.1 Underground stations shall be a minimum Type IA or Type IB constructions.

5.2.2.1.2 Open stations may be of Type IIB construction and shall not exceed in area or height as required by Table 503 for Type IIA.

5.2.2.1.3 Open at grade stations may be of any construction type allowed by the California Building Code.

Delete Section 5.2.2.2.

Amend Section 5.2.4.3 to read as follows:

5.2.4.3 Ancillary Spaces. Fire resistance ratings of separations between ancillary occupancies shall be established as required by the California Building Code.

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REFERENCED STANDARDS

Amend Section 5.2.4.3.1 to read as follows:

5.2.4.3.1 The following areas shall be separated by a two-hour fire barrier:

1. Electrical control rooms, auxiliary electrical rooms and associated battery rooms

2. Trash rooms

3. Train control rooms and associated battery rooms

4. Fan rooms

5. Emergency generator rooms

Amend Section 5.2.4.5 to read as follows:

5.2.4.5 Separation Between System and Nonsystem Occupancies.* All station public areas shall be fire separated from adjacent non-system occupancies by a one hour fire barrier, unless otherwise required by other provisions of the California Building Code.

Amend Section 5.3.1.1 to read as follows:
CBC § 319.8. High relevance — show source text
unless it can be demonstrated that_ reduced capacity meets the requirements of Section 319.8. 2. The lateral loading to or strength requirement of existing structural components is not increased beyond their capacity. 3. New structural components are detailed and connected to the existing structural components as required by the California Building Code. 4. New or relocated nonstructural components are detailed and connected to existing or new structural components as required by the California Building Code. 5. A dangerous condition is not created.

Use of ASCE 41 Tier 1 and Tier 2 deficiency only retrofit procedures are pre-approved for use where Section 317.3 does not require an

assessment.

319.12.1 State-owned buildings. [BSC] Voluntary modifications to lateral force-resisting systems conducted in accordance with Appendix A of this code and the referenced standards of the California Building Code shall be permitted.

319.12.1.1 Design documents. [BSC] When Section 319.12 is the basis for structural modifications, the approved design documents must clearly state the scope of the seismic modifications and the accepted criteria for the design. The approved design documents must clearly have the phrase “The seismic requirements of the California Existing Building Code have not been checked to determine if these structural modifications meet the full seismic evaluation and strengthening requirements of Sections 317-322: the modifications proposed are to a different seismic performance standard than would be required in Section 319 if they were not voluntary as allowed in Section 319.12.”

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319.12.2 Public schools and community colleges. [DSA-SS, DSA-SS/CC] When Section 319.12 is the basis for structural modifications, the approved design documents must clearly indicate the scope of modifications and the acceptance criteria for the design.

SECTION 320 [BSC, DSA-SS & DSA-SS/CC]—METHOD A

320.1 General. The retrofit design shall employ the Linear Static or Linear Dynamic Procedures of ASCE 41, Section 7.4.1 or 7.4.2, and comply with the applicable general requirements of ASCE 41, Chapters 6 and 7. The earthquake hazard level and performance level given specified in Section 317.5 for the building’s risk category shall be used. Structures shall be designed for seismic forces coming from any horizontal direction.

SECTION 321 [BSC, DSA-SS & DSA-SS/CC]—METHOD B

321.1 The existing or retrofitted structure shall be demonstrated to have the capability to sustain the deformation response due to the specified earthquake ground motions and meet the seismic performance requirements of Section 317. The registered design professional shall provide an evaluation of the response of the existing structure in its modified configuration and condition to the ground motions specified. If the building’s seismic performance is evaluated as satisfactory and the peer reviewer(s) and the enforcement agency concurs, then no further structural retrofit and/or repair of the lateral load-resisting system is required.
CBC § 1.11.2.3 High relevance — show source text
1.11.2.3 More restrictive fire and panic safety building standards.

1.11.2.3.1 Any fire protection district organized pursuant to Health and Safety Code Part 2.7 (commencing with Section 13800) of Division 12 may adopt building standards relating to fire and panic safety that are more stringent than those building standards adopted by the State Fire Marshal and contained in the California Building Standards Code. For these purposes, the district board shall be deemed a legislative body and the district shall be deemed a local agency. Any changes or modifications that are more stringent than the requirements published in the California Building Standards Code relating to fire and panic safety shall be subject to Section 1.1.8.1.

1.11.2.3.2 Any fire protection district that proposes to adopt an ordinance pursuant to this section shall, not less than 30 days prior to noticing a proposed ordinance for public hearing, provide a copy of that ordinance, together with the adopted findings made pursuant to Section 1.11.2.3.1, to the city, county, or city and county where the ordinance will apply. The city, county, or city and county may provide the district with written comments, which shall become part of the fire protection district’s public hearing record.

1.11.2.3.3 The fire protection district shall transmit the adopted ordinance to the city, county, or city and county where the ordi- nance will apply. The legislative body of the city, county, or city and county may ratify, modify or deny an adopted ordinance and transmit its determination to the district within 15 days of the determination. Any modification or denial of an adopted ordinance shall include a written statement describing the reasons for any modifications or denial. No ordinance adopted by the district shall be effective until ratification by the city, county, or city and county where the ordinance will apply. 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 condi- tions. 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.
CBC § 1224.30.3.5 High relevance — show source text
1224.30.3.5 Airborne infection isolation room. At least one airborne infection isolation room shall be provided within each pedi- atric unit; minimum of one per 15 beds. Airborne infection isolation room(s) shall comply with the requirements of Section 1224.14.3.

1224.30.3.6 Clean and soiled workrooms. Separate clean and soiled workrooms or holding rooms shall be provided as described in Sections 1224.14.2.6 and 1224.14.2.7.

1224.31 PSYCHIATRIC NURSING UNIT.

1224.31.1 Psychiatric unit space. A psychiatric unit shall be housed in a separate nursing unit and shall provide the following:

1224.31.1.1 General. A psychiatric nursing unit shall meet the requirements of Section 1224.14 for a unit that provides acute medical care. A non-medical psychiatric nursing unit shall meet the requirements of Sections 1228.4, 1228.13 and 1228.14 based on the functional program. Specific application shall respond to the patient injury and suicide prevention component of the Patient Safety Risk Assessment prepared under California Administrative Code (Part 1 of Title 24) Section 7-119. If a unit provides acute medical care, the unit shall be located in a building that is compliant with California Administrative Code Chapter 6 for OSHPD-1.

1224.31.1.2 Windows. Windows modified to prevent patients from leaving the unit.

1224.31.1.3 Access control. Entrances and exits which may be locked if necessary.

1224.31.1.4 Seclusion room(s). Seclusion rooms shall be provided and comply with Section 1224.4.4.1.4.

1224.31.1.5 Consultation room(s). Used for interviewing patients.

1224.31.1.6 Dining and recreation. Provide spaces for dining and recreation. The total area for these purposes shall be not less than 30 square feet (2.8 m [2] ) per patient.

1224.31.1.7 Storage. Storage closets or cabinets for recreational and occupation therapy equipment.

1224.31.1.8 Exam or treatment room. A room for physical examinations and medical treatment.

1224.31.1.9 Activity spaces. Psychiatric rehabilitation activity space shall be provided in compliance with Section 1228.13.1 except as modified as follows:

1224.31.1.9.1 Indoor activity rooms. Two separate activity rooms shall be provided; one may be the recreation room required by Section 1224.31.1.11, and one shall be for quiet activities to serve as a patient lounge. The patient lounge shall be a minimum 120 square feet (11.15 m [2] ).

1224.31.1.9.2 Outdoor activity area. The outdoor activity area shall be dedicated for use by the psychiatric nursing unit.
CBC § 319.1 Medium relevance — show source text
Buildings complying with the requirements of the exception in Section 319.1 are deemed to meet the seismic performance requirements of this section._
4. State-owned and state-leased essential services buildings are subject to the regulatory authority of DSA-SS per Section 1.9.2.1.|

317.6 Retrofit required. Where the evaluation indicates the building does not meet the required performance objectives of this section, the owner shall take appropriate steps to ensure that the building’s structural system is retrofitted in accordance with the provisions of Section 317. Appropriate steps are either: 1) undertake the seismic retrofit as part of the additions, alterations and/or repairs of the structure; or 2) provide a plan, acceptable to the building official, to complete the seismic retrofit in a timely manner. The relocation or moving of an existing building is considered to be an alteration requiring filing of the plans and specifications approved by the building official.

317.7 The additions, alteration or repair to any existing building are permitted to be prepared in accordance with the structural and nonstructural requirements for a new building as given in the California Building Code, applied to the entire building.

317.8 The requirements of ASCE 41 Chapters 14 and 15 are to apply to the use of seismic isolation and passive energy systems, respectively, for the repair, voluntary lateral-force-resisting system modification or retrofit of an existing structure. When seismic isolation or passive energy dissipation is used, the project must have project peer review as prescribed in Section 322.

317.9 Any construction required by this chapter shall include structural observation by the registered design professional who is responsible for the structural design in accordance with Section 319.10.

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317.10 Where Method B of Section 321 is used or is required by Section 319.7, the proposed method of building evaluation and design procedures must be accepted by the building official prior to the commencement of the work.

317.11 Voluntary lateral-force-resisting system modifications. Where the exception of Section 317.2 applies, modifications of existing structural components and additions of new structural components that are initiated for the purpose of improving the seismic performance of an existing structure and that are not required by other portions of this chapter are permitted under the requirements of Section 319.12.

SECTION 318 [BSC, DSA-SS & DSA-SS/CC]—DEFINITIONS

318.1 In addition to the definitions given in Section 202, for the purposes of Sections 317 through 323, certain terms are defined as follows:

[DSA-SS & DSA-SS/CC] For the purposes of Section 317 through 323, definitions of terms given in Section 4-207 or 4-314 of the California Administrative Code govern over those in Section 202.

ADDITION [BSC] means any work that increases the floor or roof area or the volume of enclosed space of an existing building, and is structurally attached to the existing building by connections that are required for transmitting vertical or horizontal loads between the addition and the existing structure.
CBC § 319.7.1 Medium relevance — show source text
319.7.1 A building with prestressed or post- tensioned structural components (beams, columns, walls or slabs) or precast structural components (beams, columns, walls or flooring systems).

319.7.2 A building classified as irregular per Section 319.5.

Exceptions: 1. The retrofit design removes the configurational attributes that caused the building to be classified as irregular. 2. The irregularity is demonstrated not to affect the seismic performance of the building.

319.7.3 A building assigned to Risk Category IV per Section 319.4.

319.7.4 A building with an undefined or hybrid structural system.

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319.7.5 A building with a seismic isolation or energy dissipation system, either as part of the existing structure or as part of the retrofit.

319.7.6 A building greater than 240 feet (73 m) in height.

319.7.7 A building evaluated per ASCE 41 and its application requires the use of a nonlinear analysis procedure.

319.8 Strength requirements. All components of the lateral-force-resisting system must have the strength to meet the acceptance criteria prescribed in ASCE 41, Chapter 7 or as prescribed in the applicable Appendix A chapter of this code if a specific procedure in Section 319.1.1 is used. Any component not having this strength shall have its capacity increased by modifying or supplementing its strength so that it exceeds the demand, or the demand is reduced to less than the existing strength by making other modifications to the structural system.

Exception: A component’s strength is permitted to be less than that required by the specified seismic load combinations if it can be demonstrated that the associated reduction in seismic performance of the component or its removal due to the failure does not result in a structural system that does not comply with the required performance objectives of Section 317. If this exception is taken for a component, then it cannot be considered part of the primary lateral-load-resisting system.

319.9 Nonstructural component requirements. Where the nonstructural performance levels required by Section 317, Table 317.5 are N-D or higher, mechanical, electrical and plumbing components shall comply with the provisions of ASCE 41, Chapter 13, Section 13.2.

Exception: Modifications to the procedures and criteria may be made subject to approval by the building official, and concurrence of the peer reviewer if applicable. All reports and correspondence shall also be forwarded to the building official.

319.10 Structural observation, testing and inspection. Structural observation, testing and inspection as used in this section shall mean meeting the requirements of Chapter 17 of the California Building Code, with a minimum allowable level of investigation corresponding to seismic design category (SDC) D. Structural observation visits shall occur at significant construction stages and at the completion of the structural retrofit. Structural observation shall be provided for all structures.

Additional requirements: [DSA-SS, DSA-SS/CC] For public schools and community colleges, construction material testing, inspection and observation during construction shall also comply with the California Administrative Code.
CBC § 319.9 Medium relevance — show source text
Exception: A component’s strength is permitted to be less than that required by the specified seismic load combinations if it can be demonstrated that the associated reduction in seismic performance of the component or its removal due to the failure does not result in a structural system that does not comply with the required performance objectives of Section 317. If this exception is taken for a component, then it cannot be considered part of the primary lateral-load-resisting system.

319.9 Nonstructural component requirements. Where the nonstructural performance levels required by Section 317, Table 317.5 are N-D or higher, mechanical, electrical and plumbing components shall comply with the provisions of ASCE 41, Chapter 13, Section 13.2.

Exception: Modifications to the procedures and criteria may be made subject to approval by the building official, and concurrence of the peer reviewer if applicable. All reports and correspondence shall also be forwarded to the building official.

319.10 Structural observation, testing and inspection. Structural observation, testing and inspection as used in this section shall mean meeting the requirements of Chapter 17 of the California Building Code, with a minimum allowable level of investigation corresponding to seismic design category (SDC) D. Structural observation visits shall occur at significant construction stages and at the completion of the structural retrofit. Structural observation shall be provided for all structures.

Additional requirements: [DSA-SS, DSA-SS/CC] For public schools and community colleges, construction material testing, inspection and observation during construction shall also comply with the California Administrative Code.

319.10.1 The requirement for structural observation shall be noted and prominently displayed on the front sheet of the approved plans and incorporated into the general notes on the approved plans.

319.10.2 Preconstruction meeting. A preconstruction meeting is mandatory for all projects which require structural observation. The meeting shall include, but is not limited to, the registered design professional, structural observer, general constructor, affected subcontractors, the project inspector and a representative of the enforcement agency (designated alternates may attend if approved by the structural observer). The structural observer shall schedule and coordinate this meeting. The purpose of the meeting is to identify and clarify all essential structural components and connections that affect the lateral and vertical load systems and to review scheduling of the required observations for the project’s structural system retrofit.

319.11 Temporary actions. When compatible with the building use, and the time phasing for both use and the retrofit program, temporary shoring or other structural support is permitted to be considered. Temporary bracing, shoring and prevention of falling hazards are permitted to be used to qualify for Item 1 in Section 319.12 that allows inadequate capability in some existing components, as long as the required performance levels given in Section 317 can be provided by the permanent structure. The consideration for such temporary actions shall be noted in the design documents.

319.12 Voluntary modifications to the lateral-force resisting system. Where modifications of existing structural components and additions of new structural components are initiated for the purpose of improving the lateral-force resisting strength or stiffness of an existing structure and they are not required by other sections of this code, then they are permitted to be designed to meet an approved seismic performance criteria provided that an engineering analysis is submitted that follows: 1. The capacity of existing structural components required to resist forces is not reduced, unless it can be demonstrated that
CBC § 319.10.2 Medium relevance — show source text
319.10.2 Preconstruction meeting. A preconstruction meeting is mandatory for all projects which require structural observation. The meeting shall include, but is not limited to, the registered design professional, structural observer, general constructor, affected subcontractors, the project inspector and a representative of the enforcement agency (designated alternates may attend if approved by the structural observer). The structural observer shall schedule and coordinate this meeting. The purpose of the meeting is to identify and clarify all essential structural components and connections that affect the lateral and vertical load systems and to review scheduling of the required observations for the project’s structural system retrofit.

319.11 Temporary actions. When compatible with the building use, and the time phasing for both use and the retrofit program, temporary shoring or other structural support is permitted to be considered. Temporary bracing, shoring and prevention of falling hazards are permitted to be used to qualify for Item 1 in Section 319.12 that allows inadequate capability in some existing components, as long as the required performance levels given in Section 317 can be provided by the permanent structure. The consideration for such temporary actions shall be noted in the design documents.

319.12 Voluntary modifications to the lateral-force resisting system. Where modifications of existing structural components and additions of new structural components are initiated for the purpose of improving the lateral-force resisting strength or stiffness of an existing structure and they are not required by other sections of this code, then they are permitted to be designed to meet an approved seismic performance criteria provided that an engineering analysis is submitted that follows: 1. The capacity of existing structural components required to resist forces is not reduced, unless it can be demonstrated that reduced capacity meets the requirements of Section 319.8. 2. The lateral loading to or strength requirement of existing structural components is not increased beyond their capacity. 3. New structural components are detailed and connected to the existing structural components as required by the California Building Code. 4. New or relocated nonstructural components are detailed and connected to existing or new structural components as required by the California Building Code. 5. A dangerous condition is not created.

Use of ASCE 41 Tier 1 and Tier 2 deficiency only retrofit procedures are pre-approved for use where Section 317.3 does not require an

assessment.

319.12.1 State-owned buildings. [BSC] Voluntary modifications to lateral force-resisting systems conducted in accordance with Appendix A of this code and the referenced standards of the California Building Code shall be permitted.

319.12.1.1 Design documents. [BSC] When Section 319.12 is the basis for structural modifications, the approved design documents must clearly state the scope of the seismic modifications and the accepted criteria for the design. The approved design documents must clearly have the phrase “The seismic requirements of the California Existing Building Code have not been checked to determine if these structural modifications meet the full seismic evaluation and strengthening requirements of Sections 317-322: the modifications proposed are to a different seismic performance standard than would be required in Section 319 if they were not voluntary as allowed in Section 319.12.”

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CBC § 1.8.2.1.3. Medium relevance — show source text
Exceptions: 1. [HCD 2] For relocated or moved buildings and maintenance, alteration, repair, addition or change of occupancy to existing buildings and accessory structures in mobilehome parks or special occupancy parks as provided in Section 1.8.2.1.3. See California Code of Regulations, Title 25, Division 1, Chapters 2 and 2.2. 2. [HCD 1] Limited-density owner-built rural dwellings.

[HCD 1] In addition to the requirements in this chapter, maintenance, alteration, repair, addition or change of occupancy to existing buildings and accessory structures under the authority of the Department of Housing and Community Development, as provided in Section 1.8.2.1.1, shall comply with California Code of Regulations, Title 25, Division 1, Chapter 1, Subchapter 1.

501.1.1 Compliance with other methods. Alterations, additions and changes of occupancy to existing buildings and structures shall comply with the provisions of this chapter or with one of the methods provided in Section 301.3.

501.1.2 Existing state-owned structures. [BSC] The provisions of Sections 317 through 322 establish minimum standards for earth- quake evaluation and design for retrofit of existing state-owned structures, including buildings owned by the University of California, the California State University and the Judicial Council.

The provisions of Sections 317 through 322 may be adopted by a local jurisdiction for earthquake evaluation and design for retrofit of existing buildings.

501.2 Fire-resistance ratings. Where approved by the code official, in buildings where an automatic sprinkler system installed in accordance with Section 903.3.1.1 or 903.3.1.2 of the California Building Code has been added, and the building is now sprinklered throughout, the required fire-resistance ratings of building elements and materials shall be permitted to meet the requirements of the current building code. The building is required to meet the other applicable requirements of the California Building Code .

Plans, investigation and evaluation reports, and other data shall be submitted indicating which building elements and materials the applicant is requesting the code official to review and approve for determination of applying the current building code fire-resistance ratings. Any special construction features, including fire-resistance-rated assemblies and smoke-resistive assemblies, conditions of occupancy, means of egress conditions, fire code deficiencies, approved modifications or approved alternative materials, design and methods of construction, and equipment applying to the building that impact required fire-resistance ratings shall be identified in the evaluation reports submitted.

501.3 Health care facilities. In Group I-2 facilities, ambulatory care facilities and outpatient clinics, any altered or added portion of an existing electrical or medical gas systems shall be required to meet installation and equipment requirements in NFPA 99.

501.4 Existing Group R occupancies. [SFM] See the California Residential Code for existing Group R-3 occupancies or Chapter 11 of the California Fire Code for all other existing Group R occupancies.

501.5 Carbon monoxide alarms. [HCD 1, SFM] Pursuant to Health and Safety Code Section 17926, carbon monoxide detection shall be provided in all existing Group R buildings, as required in Section 915 of the California Building Code or Section R315 of the California Resi- dential Code, as applicable.
CBC § 3-17 Medium relevance — show source text
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317.10 Where Method B of Section 321 is used or is required by Section 319.7, the proposed method of building evaluation and design procedures must be accepted by the building official prior to the commencement of the work.

317.11 Voluntary lateral-force-resisting system modifications. Where the exception of Section 317.2 applies, modifications of existing structural components and additions of new structural components that are initiated for the purpose of improving the seismic performance of an existing structure and that are not required by other portions of this chapter are permitted under the requirements of Section 319.12.

SECTION 318 [BSC, DSA-SS & DSA-SS/CC]—DEFINITIONS

318.1 In addition to the definitions given in Section 202, for the purposes of Sections 317 through 323, certain terms are defined as follows:

[DSA-SS & DSA-SS/CC] For the purposes of Section 317 through 323, definitions of terms given in Section 4-207 or 4-314 of the California Administrative Code govern over those in Section 202.

ADDITION [BSC] means any work that increases the floor or roof area or the volume of enclosed space of an existing building, and is structurally attached to the existing building by connections that are required for transmitting vertical or horizontal loads between the addition and the existing structure.

ALTERATION [BSC] means any change within or to an existing building, which does not increase and may decrease the floor or roof area or the volume of enclosed space.

BSE-C RESPONSE ACCELERATION PARAMETERS [BSC] are the parameters (S XS and S X1 ) taken from 5-percent/50-year maximum direction spectral response acceleration curves or by a Site Specific Response Spectrum developed in accordance with ASCE 41, Section 2.3.3.

BSE-R RESPONSE ACCELERATION PARAMETERS [BSC] are the parameters (S XS and S X1 ) taken from 20-percent /50-year maximum direction spectral response acceleration curves or by a Site Specific Response Spectrum developed in accordance with ASCE 41, Section 2.3.3.

SECTION 319 [BSC, DSA-SS & DSA-SS/CC]—SEISMIC CRITERIA SELECTION FOR EXISTING BUILDINGS

319.1 Basis for evaluation and design. This section determines what technical approach is to be used for the seismic evaluation and design for existing buildings. For those buildings or portions of buildings for which Section 317 requires action, the procedures and limitations for the evaluation of existing buildings and design of retrofit systems and/or repair thereof shall be implemented in accordance with this section.

One of the following approaches must be used: 1. Method A of Section 320;

2. Method B of Section 321, with independent review of a peer reviewer as required in Section 322; or 3. For state-owned buildings only, the use of one of the specific procedures listed in Section 319.1.1.
CBC § 0.91 Medium relevance — show source text
Quantities of high toxics in use in open systems need not be reduced_
above the third floor or below the first basement floor level. Individual container size shall be limited to 2 pounds (0.91 kg) for solids and1/4 gallon (0.95 L) for liquids.|1. A laboratory suite is a space up to 10,000 square feet (929 m2) bounded by not less than a 1-hour fire-resistive occupancy separation within which the exempt amounts of hazard-
ous materials may be stored, dispensed, handled or used. Up through the third floor and down through the first basement floor, the quantity in this table shall apply. Fourth, fifth
and sixth floors and the second and third basement floor level quantity shall be reduced to 75 percent of this table. The seventh through 10th floor and below the third basement
floor level quantity shall be reduced to 50 percent of this table.
2. Permitted only when stored or used in approved exhausted gas cabinets, exhausted enclosures or fume hoods. Quantities of high toxics in use in open systems need not be reduced
above the third floor or below the first basement floor level. Individual container size shall be limited to 2 pounds (0.91 kg) for solids and1/4 gallon (0.95 L) for liquids.|1. A laboratory suite is a space up to 10,000 square feet (929 m2) bounded by not less than a 1-hour fire-resistive occupancy separation within which the exempt amounts of hazard-
ous materials may be stored, dispensed, handled or used. Up through the third floor and down through the first basement floor, the quantity in this table shall apply. Fourth, fifth
and sixth floors and the second and third basement floor level quantity shall be reduced to 75 percent of this table. The seventh through 10th floor and below the third basement
floor level quantity shall be reduced to 50 percent of this table.
2. Permitted only when stored or used in approved exhausted gas cabinets, exhausted enclosures or fume hoods. Quantities of high toxics in use in open systems need not be reduced
above the third floor or below the first basement floor level. Individual container size shall be limited to 2 pounds (0.91 kg) for solids and1/4 gallon (0.95 L) for liquids.|

SECTION 317 [BSC, DSA-SS & DSA-SS/CC]—EARTHQUAKE EVALUATION AND DESIGN FOR RETROFIT OF EXISTING BUILDINGS

317.1 Purpose.

317.1.1 Existing state-owned structures. [BSC] The provisions of Sections 317 through 322 establish minimum standards for earthquake evaluation and design for retrofit of existing state-owned structures, including buildings owned by the University of California and the California State University.

The provisions of Sections 317 through 323 may be adopted by a local jurisdiction for earthquake evaluation and design for retrofit of existing buildings.

317.1.2 Public school buildings. [DSA-SS] The provisions of Sections 317 through 323 establish minimum standards for earthquake evaluation and design for the rehabilitation of existing buildings for use as public school buildings under the jurisdiction of the Division of the State Architect—Structural Safety [DSA-SS], refer to Section 1.9.2.1.

Frequently asked questions

When does § 317.11 apply instead of a full § 317 evaluation?

§ 317.11 applies when the exception in § 317.2 is met — i.e., when § 317.3 determines assessment is not required or § 317.4 determines retrofit is not needed — allowing voluntary modifications under § 319.12.

Is voluntary strengthening under § 319.12 “no‑documents” work?

No. § 319.12 requires an engineering analysis, clear scope and acceptance criteria; design documents must state the scope and the voluntary nature of the seismic criteria used.

Can I use ASCE 41 Tier 1/2 procedures to avoid a full assessment?

Yes — ASCE 41 Tier 1 and Tier 2 deficiency‑only procedures are pre‑approved for use where § 317.3 does not require an assessment. That means for eligible limited projects you can use Tier 1/2 procedures per the code.

Does a single structural repair that increases story shear by 11% always trigger retrofit?

An increase in story shear greater than 10% is one of the § 317.3.1 triggers that makes Section 317’s evaluation applicable. If that trigger is met, an evaluation is required; the evaluation determines whether retrofit is actually needed per § 317.4–§ 317.6.

If my project is voluntary under § 317.11, do I still need structural observation?

Yes—construction required by Chapter 317/319 that involves structural elements still carries the requirement for structural observation, testing and inspection per § 319.10 (and the CBC’s Chapter 17 minimums), unless the enforcing authority accepts otherwise.

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When is seismic evaluation/retrofit required for state-owned (and certain public) buildings?

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Are peer review or earthquake monitoring requirements applicable for existing building projects?

Seismic Evaluation & Retrofit for Existing Buildings

California Building Code