CHBC · California Historical Building Code
Are existing stairs or handrails with nonconforming dimensions allowed?
If your historic building’s stairs or handrails don’t match the regular code, the CHBC lets them remain only if the local enforcing agency determines they “do not constitute a distinct hazard” — you must present measurements and conditions to that agency for review (see **§ 8-502.3**).
Last reviewed: July 6, 2026
What the code requires — 2-4 sentences
The California Historical Building Code allows existing stairs and handrails that do not match the dimensional requirements of the regular code when the local enforcing agency determines they do not constitute a distinct hazard. Specifically, § 8-502.3 makes this allowance for risers, treads, width and for handrail grip size or extensions. The enforcing agency’s broader authority to grant reasonable exceptions where life safety is not adversely affected is stated in § 8-502.1.
The single most important rule: existing stairs or handrails that are dimensionally different from the regular code may remain in place if the enforcing agency finds they are not a distinct hazard. § 8-502.3
Requirements in detail
Fundamental test — who decides?
- The acceptance of nonconforming dimensions is a determination by the enforcing agency. This is not automatic; the agency must find the condition does not constitute a distinct hazard before allowing continued use. § 8-502.3.
- The CHBC also directs that the enforcing agency grant reasonable exceptions to egress requirements when those exceptions do not adversely affect life safety. § 8-502.1.
What elements are addressed
- Stair risers, treads, and stair width that are at variance with the regular code.
- Handrails with nonconforming grip size or extensions.
All of the above may be allowed to remain when the enforcing agency determines they do not create a distinct hazard. § 8-502.3.
Decision-relevant dimensions (decision, not fixed numeric allowances)
| Element | What CHBC allows (decision basis) | Code Reference |
|---|---|---|
| Stair riser height | May remain if enforcing agency finds it does not constitute a distinct hazard | § 8-502.3 |
| Stair tread depth | May remain if enforcing agency finds it does not constitute a distinct hazard | § 8-502.3 |
| Stair width | Existing widths below regular-code dimensions may remain if deemed not a distinct hazard | § 8-502.3 |
| Handrail grip size | Nonconforming grip sizes may be retained if not a distinct hazard | § 8-502.3 |
| Handrail extensions | Nonconforming extensions may be retained if not a distinct hazard | § 8-502.3 |
Note: The CHBC text for these provisions is permission-by-determination rather than numeric; it does not establish new numeric maxima/minima for these items in § 8-502.3.
Exceptions & special cases
- The general allowance is tempered by the enforcing agency’s life-safety evaluation: the agency must find the condition does not adversely affect life safety or constitute a distinct hazard before granting the exception. § 8-502.1 and § 8-502.3.
- Existing door openings and corridor widths smaller than regular-code dimensions are similarly allowed where there is sufficient width and height for occupants to pass — see § 8-502.2 (related context).
- CHBC contains administrative procedures and appeal routes (for example, SHBSB review and appeals) for questions of statewide significance; see the CHBC provisions on appeals and Board review (e.g., § 8-104.3) if a local decision is contested.
- The CHBC does not itself prescribe numeric replacement thresholds for stairs/handrails in § 8-502.3; where a stair or handrail is being replaced or altered, other codes or the enforcing agency’s requirements may apply — consult the enforcing agency.
Common mistakes
- Assuming a numeric “allowance” exists. The CHBC does not give alternate numeric dimensions in § 8-502.3 — it allows continuation only by agency determination. Do not treat this as an automatic numeric exception.
- Failing to document the agency determination. An accepted nonconforming condition should be documented in the project record or permit so there is a clear agency finding that it “does not constitute a distinct hazard.” § 8-502.3.
- Confusing “existing allowed to remain” with “replacement allowed to be the same.” The CHBC text allows existing items to remain; replacement or substantial alteration may trigger other code requirements — verify with the enforcing agency.
- Overlooking broader CHBC flexibility: the enforcing agency can grant reasonable exceptions across means-of-egress rules where life safety is not adversely affected. Don’t treat § 8-502.3 in isolation — it sits within the CHBC’s overall allowance framework. § 8-502.1.
Worked example
Scenario: An owner of a qualified historical building has an interior public stair where existing measurements are riser = 8-3/4 inches, tread = 9 inches, stair clear width = 32 inches, and the existing handrail grip diameter is 2-5/8 inches with no modern returned extensions.
How CHBC applies:
- These dimensions differ from the regular code’s typical requirements, but § 8-502.3 allows existing stairs and handrails that are at variance with the regular code to remain if the enforcing agency determines they do not constitute a distinct hazard. The owner should present the measurements and any occupant-use information to the enforcing agency for review. § 8-502.3.
- The enforcing agency will evaluate factors such as occupancy, frequency of use, existing conditions (lighting, nosings, visibility), and whether the configuration creates a clear hazard. If the agency finds no distinct hazard, it may allow the existing stair and handrail to remain as-is. § 8-502.1 and § 8-502.3.
- If the agency determines the configuration is a hazard, it may require targeted improvements (for example, adding a handrail extension or improving tread visibility) rather than full compliance to new-construction dimensions. The CHBC encourages reasonable, life-safety–based exceptions. § 8-502.1 and § 8-502.3.
Related provisions
- § 8-502.1 — General authority to grant reasonable exceptions where life safety is not adversely affected.
- § 8-502.2 — Existing door openings and corridor widths smaller than regular-code dimensions may be permitted where sufficient width and height exist.
- § 8-502.4 — Main entry doors (related egress provision).
- § 8-502.5 — Existing fire escapes (related egress provision).
- § 8-104.2 / 8-104.3 — SHBSB review and appeals procedures for statewide-significant disputes (administrative/appeal path).
- § 8-501.1–8-501.3 — Purpose, intent and scope for means of egress under the CHBC (context for the exceptions).
Code references
Grounded in the retrieved California Historical Building Code — click a citation to read the verbatim passage:
CHBC § 8-5 High relevance — show source text
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8-5 MEANS OF EGRESS
SECTION 8-501 — PURPOSE, INTENT AND SCOPE
8-501.1 Purpose. The purpose of this chapter is to establish minimum means of egress regulations for qualified historical buildings or properties. The CHBC requires enforcing agencies to accept reasonably equivalent alternatives to the means of egress requirements in the regular code.
8-501.2 Intent. The intent of these regulations is to provide an adequate means of egress.
8-501.3 Scope. Every qualified historical building or portion thereof shall be provided with exits as required by the CHBC when required by the provisions of Section 8-102.
SECTION 8-502 — GENERAL
8-502.1 General. The enforcing agency shall grant reasonable exceptions to the specific provisions of applicable egress regulations where such exceptions will not adversely affect life safety.
8-502.2. Existing door openings and corridor widths of less than dimensions required by regular code shall be permitted where there is sufficient width and height for the occupants to pass through the opening or traverse the exit.
8-502.3 Stairs. Existing stairs having risers and treads or width at variance with the regular code are allowed if determined by the enforcing agency to not constitute a distinct hazard. Handrails with nonconforming grip size or extensions are allowed if determined by the enforcing agency to not constitute a distinct hazard.
8-502.4 Main entry doors. The front or main entry doors need not be rehung to swing in the direction of exit travel, provided other means or conditions of exiting, as necessary to serve the total occupant load, are provided.
8-502.5 Existing fire escapes. Existing previously approved fire escapes and fire escape ladders shall be acceptable as one of the required means of egress, provided they extend to the ground and are easily negotiated, adequately signed and in good working order. Access shall be by an opening having a minimum width of 29 inches (737 mm) when open with a sill no more than 30 inches (762 mm) above the adjacent floor, landing or approved step.
8-502.6 New fire escapes and fire escape ladders. New fire escapes and fire escape ladders which comply with this section shall be acceptable as one of the required means of egress. New fire escapes and new fire escape ladders shall comply with the following:
- Access from a corridor shall not be through an intervening room.
- All openings within 10 feet (3048 mm) shall be protected by three-fourths-hour fire assemblies. When located within a recess or vestibule, adjacent enclosure walls shall be of not less than one-hour fire-resistive construction.
- Egress from the building shall be by a clear opening having a minimum dimension of not less than 29 inches (737 mm). Such openings shall be openable from the inside without the use of a key or special knowledge or effort. The sill of an opening giving access shall not be more than 30 inches (737 mm) above the floor, step or landing of the building or balcony.
- Fire escape stairways and balconies shall support the dead load plus a live load of not less than 100 pounds per square foot (4.79 kN/m [2] ) and shall be provided with a top and intermediate handrail on each side. The pitch of the stairway shall not exceed 72 degrees with a minimum width of 18 inches (457 mm).
CHBC § 8-410.3 High relevance — show source text
Buildings with floors above 75 feet, NFPA 13.
When the building is free standing or with property line separation, two floors and 1500 square feet per floor or less, NFPA 13D.
For exterior wall and opening protection. As required by this chapter.
Exception: When the automatic sprinkler systems are used to reach compliance using this code, in three or more occasions, NFPA 13D standard shall be increased to NFPA 13R standard, or NFPA 13R standard shall be increased to a NFPA 13 standard.
8-410.3 Automatic sprinkler systems shall not be used to substitute for or act as an alternate to the required number of exits from any facility. (See Chapter 8-5 for exiting requirements.)
8-410.4 An automatic sprinkler system shall be provided in all detention facilities.
SECTION 8-411 — OTHER TECHNOLOGIES
Fire alarm systems, smoke and heat detection systems, occupant notification and annunciation systems, smoke control systems and fire modeling, timed egress analysis and modeling, as well as other engineering methods and technologies may be accepted by the enforcing agency to address areas of nonconformance.
SECTION 8-412 — HIGH-RISE BUILDINGS
Qualified historical buildings having floors for human occupancy located more than 75 feet above the lowest floor level having building access shall conform to the provisions of the regular code for existing high-rise buildings as amended by the CHBC.
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8-5 MEANS OF EGRESS
SECTION 8-501 — PURPOSE, INTENT AND SCOPE
8-501.1 Purpose. The purpose of this chapter is to establish minimum means of egress regulations for qualified historical buildings or properties. The CHBC requires enforcing agencies to accept reasonably equivalent alternatives to the means of egress requirements in the regular code.
8-501.2 Intent. The intent of these regulations is to provide an adequate means of egress.
8-501.3 Scope. Every qualified historical building or portion thereof shall be provided with exits as required by the CHBC when required by the provisions of Section 8-102.
SECTION 8-502 — GENERAL
8-502.1 General. The enforcing agency shall grant reasonable exceptions to the specific provisions of applicable egress regulations where such exceptions will not adversely affect life safety.
8-502.2. Existing door openings and corridor widths of less than dimensions required by regular code shall be permitted where there is sufficient width and height for the occupants to pass through the opening or traverse the exit.
8-502.3 Stairs. Existing stairs having risers and treads or width at variance with the regular code are allowed if determined by the enforcing agency to not constitute a distinct hazard. Handrails with nonconforming grip size or extensions are allowed if determined by the enforcing agency to not constitute a distinct hazard.
8-502.4 Main entry doors. The front or main entry doors need not be rehung to swing in the direction of exit travel, provided other means or conditions of exiting, as necessary to serve the total occupant load, are provided.
CHBC § 1.1 High relevance — show source text
Exception: In-filling of floor openings and nonoccupiable appendages such as elevator and exit stairway shafts shall be permitted beyond that permitted by the California Building Code.
502 A .1.1 Risk category assignment. Where the addition and the existing building have different occupancies, the risk category of each existing and added occupancy shall be determined in accordance with Section 1604 A .5.1 of the California Building Code . Where application of that section results in a higher risk category for the existing building compared with the risk category for the existing building before the addition, such a change shall be considered a change of occupancy and shall comply with Section 506 A of this code. Where application of that section results in a higher risk category for the addition compared with the risk category for the addition by itself, the addition and any systems in the existing building required to serve the addition shall comply with the requirements of the California Building Code for new construction for the higher risk category.
502 A .1.2 Creation or extension of nonconformity. An addition shall not create or extend any nonconformity in the existing building to which the addition is being made with regard to accessibility, structural strength, supports and attachments for nonstructural components, fire safety, means of egress or the capacity of mechanical, plumbing or electrical systems.
Exception: Nonconforming supports and attachments for nonstructural components that serve the addition from within the existing building need not be altered to comply with California Building Code Section 1613 A unless the components are part of the addition’s life-safety system or are required to serve an addition assigned to Risk Category IV.
502 A .2 Flood hazard areas. For buildings and structures in flood hazard areas established in California Building Code, Section 1612 A .3, any addition that constitutes substantial improvement of the existing structure , as defined in Chapter 2, shall comply with the flood design requirements for new construction, and all aspects of the existing structure shall be brought into compliance with
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PRESCRIPTIVE COMPLIANCE METHOD
the requirements for new construction for flood design. For new foundations, foundations raised or extended upward, and replacement foundations, the foundations shall be in compliance with the requirements for new construction for flood design.
For buildings and structures in flood hazard areas established in California Building Code, Section 1612 A .3, any additions that do not constitute substantial improvement of the existing structure , as defined in Chapter 2, are not required to comply with the flood design requirements for new construction, provided that both of the following apply:
- The addition shall not create or extend a nonconformity of the existing building or structure with the flood-resistant construction requirements.
- The lowest floor of the addition shall be at or above the lower of the lowest floor of the existing building or structure or the lowest floor elevation required in Section 1612 A of the California Building Code .
502 A .3 Existing structural elements carrying gravity load. Any existing gravity load-carrying structural element for which an addition and its related alterations cause an increase in design dead, live or snow load, including snow drift effects, of more than 5 percent shall be replaced or altered as needed to carry the gravity loads required by the California Building Code for new structures.
CHBC § 5.3.2 High relevance — show source text
BO105.5.3.2 Kitchen and laundry areas. Kitchen areas shall have not fewer than two duplex receptacle outlets. Laundry areas shall have not fewer than one duplex receptacle outlet located near the laundry equipment and installed on an independent branch circuit.
BO105.5.3.3 Ground-fault circuit interruption. Ground-fault circuit interruption shall be provided on newly installed receptacle outlets if required by Chapters 34 through 43.
BO105.5.3.4 Lighting outlets. Not less than one lighting outlet controlled by a listed wall-mounted device shall be provided in every bathroom, hallway, stairway, attached garage and detached garage with electric power to illuminate outdoor entrances and exits, and in utility rooms and basements where these spaces are used for storage or contain equipment requiring service. The wall-mounted control device shall be located near an entrance to the room.
BO105.5.3.5 Clearance. Clearance for electrical service equipment shall be provided in accordance with Chapters 34 through 43.
BO105.6 Ventilation. Reconfigured spaces intended for occupancy and spaces converted to habitable or occupiable space in any work area shall be provided with ventilation in accordance with Section R325.
BO105.7 Ceiling height. Where a habitable attic or habitable space is created in an existing building, ceiling heights shall be not less than 6 feet 8 inches (2032 mm). Bathrooms, toilet rooms and laundry rooms shall have a ceiling height of not less than 6 feet 4 inches (1930 mm).
Exceptions:
- For rooms with sloped ceilings, the required floor area of the room shall have a ceiling height of not less than 5 feet (1524 mm), and not less than 50 percent of the required floor area shall have a ceiling height of not less than 6 feet 8 inches (2134 mm).
- At beams, girders, ducts or other obstructions, the ceiling height shall be not less than 6 feet 4 inches (1930 mm) from the finished floor.
BO105.8 Stairs, handrails and guards. Stairs, handrails and guards shall comply with this section.
BO105.8.1 Stair width. Existing basement stairs and handrails not otherwise being altered or modified shall be permitted to maintain their current clear width at, above and below existing handrails.
BO105.8.2 Stair headroom. Headroom height on existing basement stairs being altered or modified shall not be reduced below the existing stairway finished headroom. Existing basement stairs not otherwise being altered shall be permitted to maintain the current finished headroom.
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APPENDIX BO — EXISTING BUILDINGS AND STRUCTURES
BO105.8.3 Stair landing. Landings serving existing basement stairs being altered or modified shall not be reduced below the existing stairway landing depth and width. Existing basement stairs not otherwise being altered shall be permitted to maintain the current landing depth and width.
BO105.8.4 Stair treads and risers. An existing stairway shall not be required to comply with Section R318.7.5 where the existing space and construction does not allow a reduction in pitch or slope. Where risers are added to an existing stair, the tread and riser dimension of the added risers shall match the existing stair.
CHBC § 8-301 High relevance — show source text
Section
8-301 Purpose and Scope. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 8-302 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
8-303 Residential Occupancies. . . . . . . . . . . . . . . . . . . . . . . . . 5
CHAPTER 8-4 FIRE PROTECTION. . . . . . . . . . . . . . . . . . . . . . . 7
Section
8-401 Purpose, Intent and Scope . . . . . . . . . . . . . . . . . . . . . . . 7
8-402 Fire-resistive Construction . . . . . . . . . . . . . . . . . . . . . . . 7
8-403 Interior Finish Materials. . . . . . . . . . . . . . . . . . . . . . . . . . 7
8-404 Wood Lath and Plaster. . . . . . . . . . . . . . . . . . . . . . . . . . . 7
8-405 Occupancy Separation . . . . . . . . . . . . . . . . . . . . . . . . . . 7 8-406 Maximum Floor Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
8-407 Vertical Shafts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
8-408 Roof Covering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 8-409 Fire Alarm Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 8-410 Automatic Sprinkler Systems. . . . . . . . . . . . . . . . . . . . . 8 8-411 Other Technologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 8-412 High-rise Buildings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
CHAPTER 8-5 MEANS OF EGRESS . . . . . . . . . . . . . . . . . . . . . . 9
Section
8-501 Purpose, Intent and Scope . . . . . . . . . . . . . . . . . . . . . . . 9 8-502 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
8-503 Escape or Rescue Windows and Doors. . . . . . . . . . . . 10 8-504 Railings and Guardrails . . . . . . . . . . . . . . . . . . . . . . . . . 10
CHBC § 1104.10 High relevance — show source text
1104.10 Stair dimensions for existing stairways. Existing stairways in buildings shall be permitted to remain if the rise does not exceed 8 [1] / 4 inches (210 mm) and the run is not less than 9 inches (229 mm). Existing stairways can be rebuilt.
Exception: Other stairways approved by the fire code official.
1104.10.1 Dimensions for replacement stairways. The replacement of an existing stairway in a structure shall not be required to comply with the new stairway requirements of Section 1011 where the existing space and construction will not allow a reduction in pitch or slope.
1104.11 Winders. Existing winders shall be allowed to remain in use if they have a minimum tread depth of 6 inches (152 mm) and a minimum tread depth of 9 inches (229 mm) at a point 12 inches (305 mm) from the narrowest edge.
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CONSTRUCTION REQUIREMENTS FOR EXISTING BUILDINGS
1104.12 Curved stairways. Existing curved stairways shall be allowed to continue in use, provided that the minimum depth of tread is 10 inches (254 mm) and the smallest radius shall be not less than twice the width of the stairway.
1104.13 Stairway handrails. Stairways shall have handrails on at least one side. Handrails shall be located so that all portions of the stairway width required for egress capacity are within 44 inches (1118 mm) of a handrail.
Exception: Aisle stairs provided with a center handrail are not required to have additional handrails.
1104.13.1 Height. Handrail height, measured above stair tread nosings, shall be uniform, not less than 30 inches (762 mm) and not more than 42 inches (1067 mm).
1104.14 Slope of ramps. Ramp runs utilized as part of a means of egress shall have a running slope not steeper than 1 unit vertical in 10 units horizontal (10-percent slope). The slope of other ramps shall not be steeper than 1 unit vertical in 8 units horizontal (12.5percent slope).
1104.15 Width of ramps. Existing ramps are permitted to have a minimum width of 30 inches (762 mm) but not less than the width required for the number of occupants served as determined by Section 1005.1. In Group I-2, ramps serving as a means of egress and used for the movement of patients in beds shall comply with Section 1105.6.4.
[BE] 1104.16 Fire escape stairways. Fire escape stairways shall comply with Sections 1104.16.1 through 1104.16.6.
[BE] 1104.16.1 Existing means of egress. Fire escape stairways shall be permitted in existing buildings but shall not constitute more than 50 percent of the required exit capacity.
[BE] 1104.16.2 Opening protectives. Doors and windows within 10 feet (3048 mm) of fire escape stairways shall be protected with [3] / 4 -hour opening protectives.
Exception: Opening protectives shall not be required in buildings equipped throughout with an approved automatic sprinkler system.
CHBC § 8.2.1.2 High relevance — show source text
RESOURCE A-120 2025 CALIFORNIA EXISTING BUILDING CODE
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Accessibility 1.8.2.1.2, 1.9.1, 104.2.4, 306, 801.1, 901.2, 1101.2, 1508, Appendix B Additions Chapter 11, 101.2, 101.3, 101.4, 104.3, 104.3.1, 104.2.4.1, 106.2.3, 109.3.3, 113.2, 115.5, 202, 301.1, 301.3, 302.2, 302.2.1, 303.2, 304.1, 304.2, 307.1, 308.1, 309, 501.1, 502, 601.1, 606, 1301.1, 1301.1.1, 1302.1, 1302.1.3, 1303.1, 1304.1.1, 1304.1.3, 1501.3, 1505.2 Administration Chapter 1 Alterations Chapter 7, Chapter 8, Chapter 9, 101.2, 101.3, 101.4, 101.6, 104.3, 104.3.1, 104.3.2, 104.2.4.1, 105.1.1, 105.1.2, 105.2.2, 105.2.3, 106.2.3, 106.2.6, 108.5, 110.2, 113.2, 115.5, 202, 301.1, 301.3, 302.2, 302.2.1, 302.4, 304, 307.1, 308.1, 309.1, 501.1, 501.1.1, 502.1, 502.3, 502.4, 503, 504.1, 601.1, 602, 603, 604, 1101.3, 1103.1, 1103.2, 1301.1, 1301.1.1, 1302.1, 1302.1.4, 1302.1.6, 1303.1, 1304.1.1, 1304.1.3, 1307.1.1, 1401.2, 1501.3, 1504.1, 1505.2, A105.2, A304.1.1, A402.1, A403.2 Level 1 Chapter 7, 104.3.2, 602, 603.2, 604.2, 801.2 Level 2 Chapter 8, 106.2.3, 505.2, 603 Level 3 Chapter 9, 106.2.3, 604, 1011.4 Alternative Materials, Design and Methods of Construction 104.2.3 Ambulatory Care Facility 202, 302.2.1, 406.1.2, 408.3, 501.3, 503.15, 503.17,
CHBC § 4A-3 High relevance — show source text
CHAPTER 4A [OSHPD 1] REPAIRS . . . . . . . . . . . . . . . . . . . . .4A-3
401A General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4A-3
402A Building Elements and Materials. . . . . . . . . . . . . . . . . .4A-3
403A Fire Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4A-3
404A Means of Egress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4A-3
405A Structural. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4A-3
406A Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4A-4
407A Mechanical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4A-4
408A Plumbing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4A-5
CHAPTER 5 PRESCRIPTIVE COMPLIANCE METHOD . . . . . 5-3
501 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
502 Additions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
503 Alterations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-5
504 Fire Escapes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-7
505 Windows and Emergency Escape Openings . . . . . . . 5-8
506 Change of Occupancy. . . . . . . . . . . . . . . . . . . . . . . . . . . 5-9
507 Historic Buildings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-10
CHAPTER 5A [OSHPD 1] PRESCRIPTIVE COMPLIANCE
CHBC § 8-3 High relevance — show source text
CHAPTER 8 COMPLIANCE FORMS, WORKSHEETS AND
REFERENCE MATERIAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-3
Worksheet (WS-1) Baseline Water Use: Baseline Water Use Calculation Table . . . . . . . . . . .8-3
Worksheet (WS-2) Water Use Reduction: 12-, 20- or 25-Percent Reduction Water Use Calculation Table . . . . . . . . . . . . . . . . . . .8-4
Worksheet (WS-3) 5.105.2 Building Reuse . . . . . . . . . . . . . . . .8-4 Worksheet (WS-4) 5.409.2 Whole Building Life Cycle Assessment:. . . . . . . . . . . . . . . . . . . . . . . . .8-5 Worksheet (WS-5) 5.409.3 Product GWP Compliance—Prescriptive Path: . . . . . . . . . . . . . . . .8-5
Worksheet (WS-6) A5.105.2 Building Reuse Tier 1 and Tier 2:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5
Worksheet (WS-7) A5.409.2 Whole Building Life Cycle Assessment: . . . . . . . . . . . . . . . . . . . . . . . . 8-6 Worksheet (WS-8) A5.409.3 Product GWP Compliance—Prescriptive Path:. . . . . . . . . . . . . . . . 8-6 Worksheet (WS-9) 5.409.2 and A5.409.2 Whole Building Life Cycle Assessment: . . . . . . . . . . . . . . . . 8-7 Construction Waste Management (CWM) Plan . . . . . . . . . . . 8-8 Construction Waste Management (CWM) Worksheet. . . . . . 8-9 Construction Waste Management (CWM) Acknowledgment. . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-10 Title 23, Waters, California Code of Regulations . . . . . . . . . 8-11 Commissioning Referenced Standards for Non-energy Systems. . . . . . . . . . . . . . . . . . . . . . . . . 8-13 IES TM-15-11 Table A-1, Table 130.2-A and Table 130.2-B Uplight and Glare Ratings Tables. . . . . . . . . . . . . . 8-40
CHBC § 501A.3.3.3 High relevance — show source text
501A.3.3.3 For NPC 3 and NPC 4 or NPC 4D in SPC 2, SPC 3, SPC 4 or SPC-4D buildings, the adequacy and design of nonstructural component or equipment supports and attachments may extend only to the connection of the component or equipment to the support when the total reaction at the point of support (including the application of F p ) is less than or equal to the following limits: 1. 250 pounds for components or equipment attached to light frame walls. For the purposes of this requirement, the sum of the absolute value of all reactions due to component loads on a single stud shall not exceed 250 pounds. 2. 1,000 pounds for components or equipment attached to roofs or walls of reinforced concrete or masonry construction. 3. 2,000 pounds for components or equipment attached to floors or slabs-on-grade.
Exception: If the anchorage or bracing is configured in a manner that results in significant torsion on a supporting structural element, the effects of the nonstructural reaction force on the structural element shall be considered in the anchorage design.
501 A . 4 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.
SECTION 502 A —ADDITIONS
502 A .1 General. Additions to any building or structure shall comply with the requirements of the California Building Code for new construction. Alterations to the existing building or structure shall be made to ensure that the existing building or structure together with the addition are not less complying with the provisions of the California Building Code than the existing building or structure was prior to the addition. An existing building together with its additions shall comply with the height and area provisions of Chapter 5 of the California Building Code . Where a new occupiable roof is added to a building or structure, the occupiable roof shall comply with the provisions of the California Building Code.
Exception: In-filling of floor openings and nonoccupiable appendages such as elevator and exit stairway shafts shall be permitted beyond that permitted by the California Building Code.
502 A .1.1 Risk category assignment. Where the addition and the existing building have different occupancies, the risk category of each existing and added occupancy shall be determined in accordance with Section 1604 A .5.1 of the California Building Code . Where application of that section results in a higher risk category for the existing building compared with the risk category for the existing building before the addition, such a change shall be considered a change of occupancy and shall comply with Section 506 A of this code. Where application of that section results in a higher risk category for the addition compared with the risk category for the addition by itself, the addition and any systems in the existing building required to serve the addition shall comply with the requirements of the California Building Code for new construction for the higher risk category.
502 A .1.2 Creation or extension of nonconformity. An addition shall not create or extend any nonconformity in the existing building to which the addition is being made with regard to accessibility, structural strength, supports and attachments for nonstructural components, fire safety, means of egress or the capacity of mechanical, plumbing or electrical systems.
CHBC § 4A-5 High relevance — show source text
408A Plumbing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4A-5
CHAPTER 5 PRESCRIPTIVE COMPLIANCE METHOD . . . . . 5-3
501 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
502 Additions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
503 Alterations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-5
504 Fire Escapes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-7
505 Windows and Emergency Escape Openings . . . . . . . 5-8
506 Change of Occupancy. . . . . . . . . . . . . . . . . . . . . . . . . . . 5-9
507 Historic Buildings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-10
CHAPTER 5A [OSHPD 1] PRESCRIPTIVE COMPLIANCE
METHOD. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5A-3
501A General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5A-3
502A Additions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5A-4
503A Alterations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5A-5
504A Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5A-7
505A Reserved. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5A-7
506A Change of Occupancy. . . . . . . . . . . . . . . . . . . . . . . . . . . .5A-7
CHAPTER 6 CLASSIFICATION OF WORK . . . . . . . . . . . . . . . 6-3
CHBC § 19.1 High relevance — show source text
A nosing projection not less than [3] / 4 inch (19.1 mm) but not more than 1 [1] / 4 inches (32 mm) shall be provided on stairways with solid risers where the tread depth is less than 11 inches (279 mm). 4. See Chapter 11 and California Existing Building Code Section 503.1 for the replacement of existing stairways. [DSA-AC] For applications listed in Section 1.9.1 of the California Building Code regulated by the Division of the State Architect- Access Compliance, see Chapter 11B, Section 11B-202. 5. In Group I-3 facilities, stairways providing access to guard towers, observation stations and control rooms, not more than 250 square feet (23 m [2] ) in area, shall be permitted to have a maximum riser height of 8 inches (203 mm) and a minimum tread depth of 9 inches (229 mm). 6. [SFM] Stairways providing access to lifeguard towers not open to the public, not more than 250 square feet (23 m [2] ) in area, shall be permitted to have a maximum riser height of 8 inches (203 mm) and a minimum tread depth of 9 inches (229 mm).
[BE] 1011.5.3 Winder treads. Winder treads are not permitted in means of egress stairways except within a dwelling unit.
Exceptions:
- Curved stairways in accordance with Section 1011.9.
- Spiral stairways in accordance with Section 1011.10.
[BE] 1011.5.4 Dimensional uniformity. Stair treads and risers shall be of uniform size and shape. The tolerance between the largest and smallest riser height or between the largest and smallest tread depth shall not exceed [3] / 8 inch (9.5 mm) in any flight of stairs. The greatest winder tread depth at the walkline within any flight of stairs shall not exceed the smallest by more than [3] / 8 inch (9.5 mm).
Exceptions:
Stairways connecting stepped aisles to cross aisles or concourses shall be permitted to comply with the dimensional nonuniformity in Section 1030.14.2.
Consistently shaped winders, complying with Section 1011.5, differing from rectangular treads in the same flight of stairs.
Nonuniform riser dimension complying with Section 1011.5.4.1.
[BE] 1011.5.4.1 Nonuniform height risers. Where the bottom or top riser adjoins a sloping public way, walkway or driveway having an established grade and serving as a landing, the bottom or top riser is permitted to be reduced along the slope to less than 4 inches (102 mm) in height, with the variation in height of the bottom or top riser not to exceed 1 unit vertical in 12 units horizontal (8-percent slope) of stair width. The nosings at such nonuniform height risers shall have a distinctive marking stripe, different from any other nosing marking provided on the stair flight. The distinctive marking stripe shall be visible in descent of the stair. Marking stripes shall have a width of not less than 1 inch (25 mm) but not more than 2 inches (51 mm).
2025 CALIFORNIA FIRE CODE 10-31
Frequently asked questions
If my stair has nonconforming treads, do I automatically have to change them?
No. Under the CHBC an existing stair with nonconforming treads may remain if the enforcing agency determines it does not constitute a distinct hazard. The owner should present the condition to the enforcing agency for its determination. § 8-502.3
Who makes the call about whether something is a “distinct hazard”?
The enforcing agency for the CHBC makes that determination, using the CHBC’s criteria and life-safety judgment; appeals of significant disputes can be taken to the SHBSB under CHBC procedures. §§ 8-502.1, 8-502.3, 8-104.3
Does the CHBC give numeric alternate dimensions for acceptable existing stairs or handrails?
No. § 8-502.3 does not prescribe numeric alternate dimensions; it allows existing items to remain based on the enforcing agency’s hazard determination.
What should I bring to the enforcing agency to support keeping an existing stair or handrail?
Provide clear measurements (risers, treads, width, handrail grip and extension details), photos, occupant/use data, and any proposed modest mitigations (lighting, nosing contrast, signage) to demonstrate the condition is not a distinct hazard. § 8-502.3 and the general exception authority § 8-502.1 are the CHBC basis.
If the enforcing agency denies my request, can I appeal?
Yes — for issues of statewide significance or where further review is appropriate, CHBC appeal and SHBSB review procedures are available. See CHBC provisions on appeals and Board review. § 8-104.3.
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