CHBC · California Historical Building Code

What are the CHBC requirements for new fire escapes and fire escape ladders?

For homeowners: The CHBC allows new exterior fire escapes and ladders as one required exit if they meet specific size, load, access and protection rules in **§ 8-502.6**. Key checks are a **29‑inch minimum access opening**, sill ≤ **30 inches**, stair/balcony load **100 psf**, ladder width **15 inches** with **3/4‑inch** rungs at **12‑inch** spacing, and lowest balcony ≤ **18 feet** to grade; the building official may limit ladder length based on listed products. If you plan one, provide plans, product listings and structural data to your local building official for review (§ 8-502.6) .

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Last reviewed: July 6, 2026

What the code requires — 2-4 sentences

The California Historical Building Code accepts new fire escapes and fire escape ladders as one of the required means of egress when they meet the dimensional, structural, access and opening‑protection rules set out in § 8-502.6. Key items include minimum clear openings and sill heights for access, load and handrail requirements for stairs and balconies, specific ladder dimensions and strength, and limits on how far the lowest balcony may be above grade (§ 8-502.6) .
Note: I reviewed the uploaded CHBC text and found the detailed requirements contained in § 8-502.6 (items 1–9). I did not find separate text labelled § 8-502.6.1 through § 8-502.6.4 in the provided files; therefore the summary below is drawn from § 8-502.6 as published in the CHBC .

The single most important rule: A new fire escape or ladder that meets the dimensional, loading, access and opening‑protection requirements of § 8-502.6 may be accepted as one required means of egress for a historical building .

Requirements in detail

The CHBC lists specific requirements for new fire escapes and fire escape ladders in § 8-502.6. Below are the decision-relevant items organized for quick use, with the controlling code citation shown where the value appears.

Access and openings

  • No access from a corridor through an intervening room (access must be direct) — § 8-502.6 .
  • Access opening (door or approved window) must provide a clear opening minimum of 29 inches and be openable from the inside without a key or special knowledge/effort — § 8-502.6 .
  • The sill of the opening providing access shall not be more than 30 inches above the floor, step or landing — § 8-502.6 .
  • Openings within 10 feet horizontally of the fire escape must be protected by 3/4‑hour fire assemblies; when the opening is in a recess or vestibule, adjacent enclosure walls must be 1‑hour fire‑resistive — § 8-502.6 item 2 .

Structural, loads, handrails and railing strength

  • Fire escape stairways and balconies must support dead load + live load of not less than 100 pounds per square foot (100 psf) — § 8-502.6 item 4 .
  • Provide a top and intermediate handrail on each side of stairways — § 8-502.6 item 4 .
  • All stair and balcony railings must support a horizontal force of not less than 50 pounds per lineal foot of railing — § 8-502.6 item 4 .

Stairway and balcony dimensions

  • Maximum stair pitch: 72 degrees; minimum stair width: 18 inches — § 8-502.6 item 4 .
  • Treads: not less than 4 inches in width; rise between treads: not more than 10 inches — § 8-502.6 item 4 .
  • Balcony minimum width: 44 inches; balcony balustrade height not less than 36 inches and baluster spacing no more than 9 inches — § 8-502.6 item 5 .
  • Stairway openings in balconies: minimum 22 inches by 44 inches — § 8-502.6 item 5 .

Ladders and roof access

  • For buildings four or more stories with roofs less than a 4:12 slope, the fire escape shall extend to the roof or provide an approved gooseneck ladder between the top floor landing and the roof — § 8-502.6 item 6 .
  • Fire escape ladders must be designed and connected to resist a horizontal force of 100 pounds applied anywhere on the rung — § 8-502.6 item 6 .
  • Ladder minimum width: 15 inches; ladder must be located within 12 inches of the building face — § 8-502.6 item 6 .
  • Ladder rungs: 3/4 inch (19.1 mm) diameter, spaced 12 inches on center — § 8-502.6 item 6 .
  • Roof access opening minimum: 30 inches by 33 inches — § 8-502.6 item 6 .

Termination, limits and maintenance

  • The lowest balcony shall not be more than 18 feet from the ground; fire escapes must extend to the ground or have counterbalanced stairs reaching the ground — § 8-502.6 items 7 and 6 .
  • Fire escapes shall not replace stairways required by the original code under which the building was constructed — § 8-502.6 item 8 .
  • Fire escapes shall be kept clear, unobstructed and maintained in good working order — § 8-502.6 item 9 .
  • The length of fire escapes and exit ladder devices may be limited by the building official based on listed products — § 8-502.6 item 6 .

Quick reference table — decision‑relevant dimensions & values

Dimension or requirement Required value Code Reference
Minimum clear opening for egress to fire escape 29 inches § 8-502.6
Maximum sill height above floor/landing 30 inches § 8-502.6
Opening protection distance within 10 ft → 3/4‑hour assemblies § 8-502.6 (item 2)
Stair/balcony live load 100 psf § 8-502.6 (item 4)
Stair pitch (max) 72° § 8-502.6 (item 4)
Stair width (min) 18 inches § 8-502.6 (item 4)
Tread depth (min) 4 inches § 8-502.6 (item 4)
Rise between treads (max) 10 inches § 8-502.6 (item 4)
Balcony width (min) 44 inches § 8-502.6 (item 5)
Balcony balustrade height (min) 36 inches § 8-502.6 (item 5)
Baluster spacing (max) 9 inches § 8-502.6 (item 5)
Lowest balcony max distance to ground 18 feet § 8-502.6 (item 7)
Ladder width (min) 15 inches § 8-502.6 (item 6)
Ladder rung diameter 3/4 inch § 8-502.6 (item 6)
Ladder rung spacing 12 inches on center § 8-502.6 (item 6)
Ladder horizontal force capacity 100 pounds on rung § 8-502.6 (item 6)
Railing horizontal load capacity 50 lb / lineal foot § 8-502.6 (item 4)

Exceptions & special cases

  • The CHBC allows the enforcing agency to grant reasonable exceptions where life safety is not adversely affected (see § 8-502.1) — use of discretion is expected in historical buildings .
  • For buildings equipped throughout with an approved automatic sprinkler system, other codes sometimes exempt opening protection; the CHBC text requires 3/4‑hour protection within 10 ft (see § 8-502.6 item 2) and the uploaded CHBC does not explicitly list the sprinkler exception in § 8-502.6; check with the enforcing agency for equivalencies or accepted alternatives in sprinklered buildings .
  • The CHBC explicitly says fire escapes cannot replace stairways required by the original code(s) for the building — do not assume you may delete required interior stairs by installing an exterior fire escape (§ 8-502.6 item 8) .
  • The CHBC delegates some limits (for example total permitted length of some ladder devices) to the building official, based on product listings — expect plan review and possible product listing documentation (§ 8-502.6 item 6) .

Common mistakes

  • Misreading the CHBC values against other codes: for example, the CHBC permits a 72° stair pitch for fire escapes (not the stricter 60° sometimes seen in other chapters); always cite § 8-502.6 for historical‑building work .
  • Forgetting the 3/4‑hour opening protection requirement for openings within 10 ft of the escape — windows/doors near the escape often get overlooked (§ 8-502.6 item 2) .
  • Installing a ladder or exit device that is too far from the building face or with incorrect rung spacing/diameter (must be within 12 inches, 3/4‑inch rungs, 12‑inch spacing) — see § 8-502.6 item 6 .
  • Assuming a fire escape can substitute for required interior stairs — CHBC prohibits replacing code‑required stairways with fire escapes (§ 8-502.6 item 8) .
  • Not providing counterbalanced stairs or ground termination where the lowest balcony exceeds 18 feet to grade — plan reviewers commonly check this (§ 8-502.6 item 7) .

Worked example — 4‑story historic apartment building

Scenario: A four‑story qualified historical apartment building needs an additional exterior egress from the top floor. You propose a new fire escape that starts at the top‑floor balcony and terminates with a ladder to the roof and a counterbalanced stair to grade.

Checklist against § 8-502.6:

  • Access opening: provide a door or window with a clear opening ≥ 29 in and sill ≤ 30 in above the balcony floor — meets § 8-502.6 item 3 .
  • Balcony: design balcony ≥ 44 in wide, balustrade ≥ 36 in high, balusters ≤ 9 in spacing — meets § 8-502.6 item 5 .
  • Stairway: design to support 100 psf, include top and intermediate handrails each side, stair width ≥ 18 in, tread ≥ 4 in, rise ≤ 10 in, and keep pitch ≤ 72° — meets § 8-502.6 item 4 .
  • Roof access: because the building is four stories and roof slope < 4:12, extend escape to roof or provide an approved gooseneck ladder; ladder must be ≥ 15 in wide, within 12 in of building, rungs 3/4 in diameter at 12 in o.c., and resist 100 lb horizontally on a rung — meets § 8-502.6 item 6 .
  • Ground termination: ensure the lowest balcony is ≤ 18 ft above grade or provide counterbalanced stairs to ground — meets § 8-502.6 item 7 .

Action: Submit structural calculations showing the 100 psf live load capacity, handrail and railing load design (50 lb/lf), ladder product data showing rung strength and listing, and plans that show the 29‑inch access opening and 30‑inch sill compliance. The building official may limit the ladder length by product listing — include manufacturer listing and test data (§ 8-502.6 item 6) .

Related provisions (CHBC)

  • § 8-502.1 — General allowance for reasonable exceptions by the enforcing agency (applies to means‑of‑egress rules) .
  • § 8-502.5 — Acceptance criteria for existing fire escapes and ladders (useful for comparison) .
  • § 8-503 — Escape or rescue windows and doors (minimum clear area and operability requirements that affect access to fire escapes) .
  • § 8-302.6 / 8-303.4 — Fire‑resistive construction and residential references to fire escapes (see chapter cross‑references) .
  • Refer to the enforcing agency and building official for any product‑listing/length limitations mentioned in § 8-502.6 .

Code references

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

  • CHBC § 8-502.6 High relevance — show source text

    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:

    1. Access from a corridor shall not be through an intervening room.
    2. 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.
    3. 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.
    4. 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). Treads shall not be less than 4 inches (102 mm) in width, and the rise between treads shall not exceed 10 inches (254 mm). All stair and balcony railings shall support a horizontal force of not less than 50 pounds per lineal foot (729.5 N/m [2] ) of railing.
    5. Balconies shall not be less than 44 inches (1118 mm) in width with no floor opening other than the stairway opening greater than [5] / 8 inch (15.9 mm) in width. Stairway openings in such balconies shall not be less than 22 inches by 44 inches (559 by 1118 mm). The balustrade of each balcony shall not be less than 36 inches (914 mm) high with not more than 9 inches (287 mm) between balusters.
    6. Fire escapes shall extend to the roof or provide an approved gooseneck ladder between the top floor landing and the roof when serving buildings four or more stories in height having roofs with less than 4 units vertical in 12 units horizontal (33.3 percent slope). Fire escape ladders shall be designed and connected to the building to withstand a horizontal force of 100 pounds (445 N) placed anywhere on the rung. All ladders shall be at least 15 inches (381 mm) wide, located within 12 inches (305 mm) of the building. Ladder rungs shall be [3] / 4 inch (19.1 mm) in diameter and shall be located 12 inches (305 mm) on center. Openings for roof access ladders through cornices and similar projections shall have minimum dimensions of 30 inches by 33 inches (762 by 838 mm). The length of fire escapes and exit ladder devices shall be limited to that approved by the building official based on products listed by a recognized testing laboratory.
    7. The lowest balcony shall not be more than 18 feet (5486 mm) from the ground. Fire escapes shall extend to the ground or be provided with counterbalanced stairs reaching to the ground.
    8. Fire escapes shall not take the place of stairways required by the codes under which the building was constructed.
  • CHBC § 8-5 High relevance — show source text

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    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:

    1. Access from a corridor shall not be through an intervening room.
    2. 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.
    3. 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.
    4. 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 § 804.5.1.2.2 High relevance — show source text

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    ALTERATIONS—LEVEL 2

    1. Newly constructed fire escapes shall be permitted only where exterior stairways cannot be utilized because of lot lines.

    2. Openings within 10 feet (3048 mm) of fire escape stairways shall be protected by fire assemblies having minimum [3] / 4 hour fire-resistance ratings. Exception: Opening protection shall not be required in buildings equipped throughout with an approved automatic sprinkler system.

    3. In all buildings of Group E occupancy, up to and including the 12th grade, buildings of Group I occupancy, rooming houses and childcare centers, ladders of any type are prohibited on fire escapes used as a required means of egress.

    804.5.1.2.2 Construction. The fire escape shall be designed to support a live load of 100 pounds per square foot (4788 Pa) and shall be constructed of steel or other approved noncombustible materials. Fire escapes constructed of wood not less than nominal 2 inches (51 mm) thick are permitted on buildings of Type V construction. Walkways and railings located over or supported by combustible roofs in buildings of Types III and IV construction are permitted to be of wood not less than nominal 2 inches (51 mm) thick.

    804.5.1.2.3 Dimensions. Stairways shall be not less than 22 inches (559 mm) wide with risers not more than, and treads not less than, 8 inches (203 mm). Landings at the foot of stairways shall be not less than 40 inches (1016 mm) wide by 36 inches (914 mm) long and located not more than 8 inches (203 mm) below the door.

    804.5.2 Mezzanines. Mezzanines in the work area and with an occupant load of more than 50 or in which the travel distance to an exit exceeds 75 feet (22 860 mm) shall have access to not fewer than two independent means of egress.

    Exception: Two independent means of egress are not required where the travel distance to an exit does not exceed 100 feet (30 480 mm) and the building is protected throughout with an automatic sprinkler system.

    804.5.3 Main entrance—Group A. Buildings of Group A with an occupant load of 300 or more shall be provided with a main entrance capable of serving as the main exit with an egress capacity of not less than one-half of the total occupant load. The remaining exits shall be capable of providing one-half of the total required exit capacity.

    Exception: Where a main exit is not well defined or where multiple main exits are provided, exits shall be permitted to be distributed around the perimeter of the building provided that the total width of egress is not less than 100 percent of the required width.

    804.6 Egress doorways. Egress doorways in any work area shall comply with Sections 804.6.1 through 804.6.5.

    804.6.1 Two egress doorways required. Work areas shall be provided with two egress doorways in accordance with the requirements of Sections 804.6.1.1 and 804.6.1.2.

    804.6.1.1 Occupant load and travel distance. In any work area, all rooms and spaces having an occupant load greater than 50 or in which the travel distance to an exit exceeds 75 feet (22 860 mm) shall have not fewer than two egress doorways.

  • CHBC § 504.1 High relevance — show source text

    [BE] 504.1 Where permitted. Fire escapes shall be permitted only as provided for in Sections 504.1.1 through 504.1.4.

    [BE] 504.1.1 New buildings. Fire escapes shall not constitute any part of the required means of egress in new buildings.

    [BE] 504.1.2 Existing fire escapes. Existing fire escapes shall continue to be accepted as a component in the means of egress in existing buildings only.

    2025 CALIFORNIA EXISTING BUILDING CODE 5-7

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    PRESCRIPTIVE COMPLIANCE METHOD

    [BE] 504.1.3 New fire escapes. New fire escapes for existing buildings shall be permitted only where exterior stairways cannot be utilized because of lot lines limiting stairway size or because of sidewalks, alleys or roads at grade level. New fire escapes shall not incorporate ladders or access by windows.

    [BE] 504.1.4 Limitations. Fire escapes shall comply with this section and shall not constitute more than 50 percent of the required number of exits nor more than 50 percent of the required exit capacity.

    [BE] 504.2 Location. Where located on the front of the building and where projecting beyond the building line, the lowest landing shall be not less than 7 feet (2134 mm) or more than 12 feet (3658 mm) above grade, and shall be equipped with a counterbalanced stairway to the street. In alleyways and thoroughfares less than 30 feet (9144 mm) wide, the clearance under the lowest landing shall be not less than 12 feet (3658 mm).

    [BE] 504.3 Construction. The fire escape shall be designed to support a live load of 100 pounds per square foot (4788 Pa) and shall be constructed of steel or other approved noncombustible materials. Fire escapes constructed of wood not less than nominal 2 inches (51 mm) thick are permitted on buildings of Type V construction. Walkways and railings located over or supported by combustible roofs in buildings of Type III and IV construction are permitted to be of wood not less than nominal 2 inches (51 mm) thick.

    [BE] 504.4 Dimensions. Stairways shall be not less than 22 inches (559 mm) wide with risers not more than, and treads not less than, 8 inches (203 mm) and landings at the foot of stairways not less than 40 inches (1016 mm) wide by 36 inches (914 mm) long, located not more than 8 inches (203 mm) below the door.

    [BE] 504.5 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 protection shall not be required in buildings equipped throughout with an approved automatic sprinkler system.

    SECTION 505—WINDOWS AND EMERGENCY ESCAPE OPENINGS

    505.1 Replacement windows. The installation or replacement of windows shall be as required for new installations.

    **505.2 Window fall prevention on replacement windows.

  • CHBC § 903.3.1.1 High relevance — show source text

    Group B, F and S occupancies in buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 of the_California Fire Code_ or on the
    roof of such buildings shall have a maximum exit access travel distance of 100 feet.|

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    804.5.1.2 Fire escapes required. Where more than one exit is required, an existing fire escape complying with Section 804.5.1.2.1 shall be accepted as providing one of the required means of egress.

    804.5.1.2.1 Fire escape access and details. Fire escapes shall comply with all of the following requirements:

    1. Occupants shall have unobstructed access to the fire escape without having to pass through a room subject to locking.
    2. Access to a fire escape shall be through a door, except that windows shall be permitted to provide access from single dwelling units or sleeping units in Group R-1 and R-2 occupancies or to provide access from spaces having a maximum occupant load of 10 in other occupancy classifications. 2.1. The window shall have a minimum net clear opening of 5.7 square feet (0.53 m [2] ) or 5 square feet (0.46 m [2] ) where located at grade. 2.2. The minimum net clear opening height shall be 24 inches (610 mm) and net clear opening width shall be 20 inches (508 mm). 2.3. The bottom of the clear opening shall not be greater than 44 inches (1118 mm) above the floor. 2.4. The operation of the window shall comply with the operational constraints of the California Building Code .

    8-6 2025 CALIFORNIA EXISTING BUILDING CODE

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    ALTERATIONS—LEVEL 2

    1. Newly constructed fire escapes shall be permitted only where exterior stairways cannot be utilized because of lot lines.

    2. Openings within 10 feet (3048 mm) of fire escape stairways shall be protected by fire assemblies having minimum [3] / 4 hour fire-resistance ratings. Exception: Opening protection shall not be required in buildings equipped throughout with an approved automatic sprinkler system.

    3. In all buildings of Group E occupancy, up to and including the 12th grade, buildings of Group I occupancy, rooming houses and childcare centers, ladders of any type are prohibited on fire escapes used as a required means of egress.

    804.5.1.2.2 Construction. The fire escape shall be designed to support a live load of 100 pounds per square foot (4788 Pa) and shall be constructed of steel or other approved noncombustible materials. Fire escapes constructed of wood not less than nominal 2 inches (51 mm) thick are permitted on buildings of Type V construction. Walkways and railings located over or supported by combustible roofs in buildings of Types III and IV construction are permitted to be of wood not less than nominal 2 inches (51 mm) thick.

    804.5.1.2.3 Dimensions. Stairways shall be not less than 22 inches (559 mm) wide with risers not more than, and treads not less than, 8 inches (203 mm). Landings at the foot of stairways shall be not less than 40 inches (1016 mm) wide by 36 inches (914 mm) long and located not more than 8 inches (203 mm) below the door.

  • CHBC § 504.3 High relevance — show source text

    [BE] 504.3 Construction. The fire escape shall be designed to support a live load of 100 pounds per square foot (4788 Pa) and shall be constructed of steel or other approved noncombustible materials. Fire escapes constructed of wood not less than nominal 2 inches (51 mm) thick are permitted on buildings of Type V construction. Walkways and railings located over or supported by combustible roofs in buildings of Type III and IV construction are permitted to be of wood not less than nominal 2 inches (51 mm) thick.

    [BE] 504.4 Dimensions. Stairways shall be not less than 22 inches (559 mm) wide with risers not more than, and treads not less than, 8 inches (203 mm) and landings at the foot of stairways not less than 40 inches (1016 mm) wide by 36 inches (914 mm) long, located not more than 8 inches (203 mm) below the door.

    [BE] 504.5 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 protection shall not be required in buildings equipped throughout with an approved automatic sprinkler system.

    SECTION 505—WINDOWS AND EMERGENCY ESCAPE OPENINGS

    505.1 Replacement windows. The installation or replacement of windows shall be as required for new installations.

    505.2 Window fall prevention on replacement windows. In Group R-1, R-2 or R-3 buildings containing dwelling or sleeping units, and one- and two-family dwellings and townhouses regulated by the California Residential Code, window opening control devices or other window fall prevention devices complying with ASTM F2090 shall be installed where an existing window is replaced and where all of the following apply to the replacement window:

    1. The window is operable.
    2. One of the following applies: 2.1. The window replacement includes replacement of the sash and frame. 2.2. The window replacement includes the sash only where the existing frame remains.
    3. One of the following applies: 3.1. In Group R-2 or R-3 buildings containing dwelling or sleeping units, the bottom of the clear opening of the window opening is at a height less than 36 inches (915 mm) above the finished floor. 3.2. In one- and two-family dwellings and townhouses regulated by the California Residential Code, the bottom of the clear opening of the window opening is at a height less than 24 inches (610 mm) above the finished floor.
    4. The window will permit openings that will allow passage of a 4-inch-diameter (102 mm) sphere when the window is in its largest opened position.
    5. The vertical distance from the bottom of the clear opening of the window opening to the finished grade or other surface below, on the exterior of the building, is greater than 72 inches (1829 mm).

    Exception: Operable windows where the bottom of the clear opening of the window opening is located more than 75 feet (22 860 mm) above the finished grade or other surface below, on the exterior of the room, space or building, and that are provided with window fall prevention devices that comply with ASTM F2006.

  • CHBC § 314.7 High relevance — show source text

    Note: It is the intent of this provisions that existing wood frames may have their use continued.

    314.7 New construction. All new construction shall be composed of materials and assemblies of materials conforming to the fire-resistive provisions of these regulations. In no case shall enclosure walls be required to be of more than one-hour fire-resistive construction.

    Exception: When approved by the enforcing agency, materials specified in Section 314.6 may be used for new construction when necessary to maintain continuity of design and measurement of existing construction.

    314.8 Exits. Every floor from an existing high-rise building shall have access to two separate means of egress, one of which, when approved by the enforcing agency, may be an existing exterior fire escape. New installations of smoke-proof enclosures shall not be required.

    Note: In determining the adequacy of exits and their design, Chapter 10 of the California Building Code may be used as a guide. It is the intent of this section that every existing high-rise building need not mandatorily conform or be made to conform with the requirements for new high-rise buildings. Reasonable judgment in the application of requirements must be exercised by the enforcing agency.

    314.9 Fire escapes. An existing fire escape in good structural condition may be acceptable as one of the required means of egress from each floor. Access to such fire escapes may be by any one of the following: 1. Through a room between the corridor and the fire escape if the door to the room is operable from the corridor side without the use of any key, special knowledge or effort. 2. By a door operable to a fire escape from the interior without the use of any key, special knowledge or effort. 3. By a window operable from the interior. Such window shall have a minimum dimension of 29 inches (737 mm) when open. 4. The sill shall not be more than 30 inches (762 mm) above the floor and landing.

    314.10 Protection of exterior openings. When an existing fire escape is accepted as one of the require means of egress, openings onto the fire escape landing and openings within 5 feet (1524 mm) horizontally of the landings shall be protected in a manner acceptable to the enforcing agency.

    314.11 Locking of stairway doors. When exit doors from corridors to exit stairways are locked to prohibit access from the stairway side, the locking mechanisms shall be retracted to the unlocked position upon failure of electrical power and a telephone or other two-way communication system connected to an approved emergency service that operates continuously shall be provided at not less than every fifth floor in each required stairway. In lieu thereof, master keys which will unlock all such doors from the stairway side shall be provided in such numbers and locations as approved by the enforcing agency.

    314.12 Enclosures. Interior vertical shafts, including but not limited to, elevators, stairway and utility, shall be enclosed with construction as set forth in Section 314.6.

    314.13 Opening protection. Doors in other than elevators, which shall be of a type acceptable to the enforcing agency, shall be approved one-hour, fire-rated, tight-fitting or gasketed doors or equivalent protection, and shall be of the normally closed type, self- closing or a type which will close automatically in accordance with Section 715 of the California Building Code.

  • CHBC § 44.5 High relevance — show source text

    All such assemblies shall be in good repair, free of any condition which_ would diminish their original fire-resistive characteristics. Where 1 [3] / 4 -inch (44.5 mm) solid-bonded wood-core doors are specified in these regulations for existing high-rise buildings, new or existing 1 [3] / 8 -inch (34.9 mm) doors shall be acceptable where existing framing will not accommodate a 1 [3] / 4 -inch (44.5 mm) door.

    Note: It is the intent of this provisions that existing wood frames may have their use continued.

    1114.7 New construction. All new construction shall be composed of materials and assemblies of materials conforming to the fire-resis- tive provisions of these regulations. In no case shall enclosure walls be required to be of more than one-hour fire-resistive construction.

    Exception: When approved by the enforcing agency, materials specified in Section 1114.6 may be used for new construction when necessary to maintain continuity of design and measurement of existing construction.

    1114.8 Exits. Every floor from an existing high-rise building shall have access to two separate means of egress, one of which, when approved by the enforcing agency, may be an existing exterior fire escape. New installations of smoke-proof enclosures shall not be required.

    Note: In determining the adequacy of exits and their design, Chapter 10 of the California Building Code may be used as a guide. It is the intent of this section that every existing high-rise building need not mandatorily conform or be made to conform with the requirements for new high-rise buildings. Reasonable judgment in the application of requirements must be exercised by the enforcing agency.

    1114.9 Fire escapes. An existing fire escape in good structural condition may be acceptable as one of the required means of egress from each floor. Access to such fire escapes may be by any one of the following:

    Through a room between the corridor and the fire escape if the door to the room is operable from the corridor side without the use of any key, special knowledge or effort.

    By a door operable to a fire escape from the interior without the use of any key, special knowledge or effort.

    By a window operable from the interior. Such window shall have a minimum dimension of 29 inches (737 mm) when open.

    The sill shall not be more than 30 inches (762 mm) above the floor and landing.

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    CONSTRUCTION REQUIREMENTS FOR EXISTING BUILDINGS

    1114.10 Protection of exterior openings. When an existing fire escape is accepted as one of the require means of egress, openings onto the fire escape landing and openings within 5 feet (1524 mm) horizontally of the landings shall be protected in a manner acceptable to the enforcing agency.

  • CHBC § 33.3 High relevance — show source text

    Stairway openings in such balconies shall not be less than 22 inches by 44 inches (559 by 1118 mm). The balustrade of each balcony shall not be less than 36 inches (914 mm) high with not more than 9 inches (287 mm) between balusters. 6. Fire escapes shall extend to the roof or provide an approved gooseneck ladder between the top floor landing and the roof when serving buildings four or more stories in height having roofs with less than 4 units vertical in 12 units horizontal (33.3 percent slope). Fire escape ladders shall be designed and connected to the building to withstand a horizontal force of 100 pounds (445 N) placed anywhere on the rung. All ladders shall be at least 15 inches (381 mm) wide, located within 12 inches (305 mm) of the building. Ladder rungs shall be [3] / 4 inch (19.1 mm) in diameter and shall be located 12 inches (305 mm) on center. Openings for roof access ladders through cornices and similar projections shall have minimum dimensions of 30 inches by 33 inches (762 by 838 mm). The length of fire escapes and exit ladder devices shall be limited to that approved by the building official based on products listed by a recognized testing laboratory. 7. The lowest balcony shall not be more than 18 feet (5486 mm) from the ground. Fire escapes shall extend to the ground or be provided with counterbalanced stairs reaching to the ground. 8. Fire escapes shall not take the place of stairways required by the codes under which the building was constructed. 9. Fire escapes shall be kept clear and unobstructed at all times and maintained in good working order.

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    MEANS OF EGRESS

    SECTION 8-503 — ESCAPE OR RESCUE WINDOWS AND DOORS

    Basements in dwelling units and every sleeping room below the fourth floor shall have at least one openable window or door approved for emergency escape which shall open directly into a public street, public way, yard or exit court. Escape or rescue windows or doors shall have a minimum clear area of 3.3 square feet (0.31 m [2] ) and a minimum width or height dimension of 18 inches (457 mm) and be operable from the inside to provide a full, clear opening without the use of special tools.

    SECTION 8-504 — RAILINGS AND GUARDRAILS

    The height of railings and guard railings and the spacing of balusters may continue in their historical height and spacing unless a distinct hazard has been identified or created by a change in use or occupancy.

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    8-6 ACCESSIBILITY

    SECTION 8-601 — PURPOSE, INTENT AND SCOPE

    8-601.1 Purpose. The purpose of the CHBC is to provide alternative regulations to facilitate access and use by persons with disabilities to and throughout facilities designated as qualified historical buildings or properties. These regulations require enforcing agencies to accept alternatives to regular code when dealing with qualified historical buildings or properties.

  • CHBC § 503.17 High relevance — show source text

    503.17 Ambulatory care facilities. Where a work area exceeds 50 percent of the building area and the work area includes an existing ambulatory care facility, the following shall be provided:

    1. A smoke compartment in accordance with Section 422.3 of the California Building Code where the alteration results in an ambulatory care facility greater than 10,000 square feet on one story.
    2. Separation from adjacent spaces in accordance with Section 422.2 of the California Building Code, where any such facility has the potential for four or more care recipients are to be incapable of self-preservation at any time.

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

    503.19 Locking arrangements in educational occupancies. In Group E occupancies, Group B educational occupancies and Group I4 occupancies, egress doors with locking arrangements designed to keep intruders from entering the room shall comply with Section 1010.2.8 of the California Building Code .

    503.20 Two-way communications systems. Where the work area for alterations exceeds 50 percent of the building area and the building has elevator service, a two-way communication systems shall be provided where required by Section 1009.8 of the Califor- nia Building Code .

    SECTION 504—FIRE ESCAPES (NOT ADOPTED BY HCD)

    [BE] 504.1 Where permitted. Fire escapes shall be permitted only as provided for in Sections 504.1.1 through 504.1.4.

    [BE] 504.1.1 New buildings. Fire escapes shall not constitute any part of the required means of egress in new buildings.

    [BE] 504.1.2 Existing fire escapes. Existing fire escapes shall continue to be accepted as a component in the means of egress in existing buildings only.

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    PRESCRIPTIVE COMPLIANCE METHOD

    [BE] 504.1.3 New fire escapes. New fire escapes for existing buildings shall be permitted only where exterior stairways cannot be utilized because of lot lines limiting stairway size or because of sidewalks, alleys or roads at grade level. New fire escapes shall not incorporate ladders or access by windows.

    [BE] 504.1.4 Limitations. Fire escapes shall comply with this section and shall not constitute more than 50 percent of the required number of exits nor more than 50 percent of the required exit capacity.

    [BE] 504.2 Location. Where located on the front of the building and where projecting beyond the building line, the lowest landing shall be not less than 7 feet (2134 mm) or more than 12 feet (3658 mm) above grade, and shall be equipped with a counterbalanced stairway to the street. In alleyways and thoroughfares less than 30 feet (9144 mm) wide, the clearance under the lowest landing shall be not less than 12 feet (3658 mm).

  • CHBC § 1113.2 High relevance — show source text

    1113.2 Number of exits. Every apartment and every other sleeping room shall have access to not less than two exits when the occupant load is 10 or more (exits need not be directly from the apartment or sleeping room). A fire escape as specified herein may be used as one required exit.

    Subject to approval of the authority having jurisdiction, a ladder device as specified herein may be used in lieu of a fire escape when the construction feature or the location of the building on the property cause the installation of a fire escape to be impractical.

    1113.3 Stair construction. All stairs shall have a minimum run of 9 inches (229 mm) and a maximum rise of 8 inches (203 mm) and a minimum width exclusive of handrails of 30 inches (762 mm). Every stairway shall have at least one handrail. A landing having a mini- mum horizontal dimension of 30 inches (762 mm) shall be provided at each point of access to the stairway.

    1113.4 Interior stairways. Every interior stairway shall be enclosed with walls of not less than one-hour fire-resistive construction. Where existing partitions form part of a stairwell enclosure, wood lath and plaster in good condition will be acceptable in lieu of one- hour fire-resistive construction. Doors to such enclosures shall be protected by a self-closing door equivalent to a solid wood door with a thickness of not less than 1 [3] / 4 inches (44.5 mm).

    Enclosures shall include all landings between flights and any corridors, passageways or public rooms necessary for continuous exit to the exterior of the buildings. The stairway need not be enclosed in a continuous shaft if cut off at each story by the fire-resistive construc- tion required by this subsection for stairwell enclosures. Enclosures shall not be required if an automatic sprinkler system is provided for all portions of the building except bedrooms, apartments and rooms accessory thereto. Interior stairs and vertical openings need not be enclosed in two-story buildings.

    1113.5 Exterior stairways. Exterior stairways shall be noncombustible or of wood of not less than 2-inch (51 mm) nominal thickness with solid treads and risers.

    1113.6 Fire escapes, exit ladder devices. Fire escapes may be used as one means of egress if the pitch does not exceed 60 degrees, the width is not less than 18 inches (457 mm), the treads are not less than 4 inches (102 mm) wide, and they extend to the ground or are provided with counterbalanced stairs reaching to the ground. Access shall be by an opening having a minimum dimension of 29 inches (737 mm) when open. The sill shall not be more than 30 inches (762 mm) above the floor and landing.

    A ladder device, when used in lieu of a fire escape, shall conform to Section 1113.6.1 and the following:

    Serves an occupant load of nine people or less or a single dwelling unit or hotel room.

    The building does not exceed three stories in height.

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    CONSTRUCTION REQUIREMENTS FOR EXISTING BUILDINGS

    The access is adjacent to an opening as specified for emergency egress or rescue or from a balcony.

    The device does not pass in front of any building opening below the unit being served.

  • CHBC § 313.2 Medium relevance — show source text

    313.2 Number of exits. Every apartment and every other sleeping room shall have access to not less than two exits when the occupant load is 10 or more (exits need not be directly from the apartment or sleeping room). A fire escape as specified herein may be used as one required exit.

    Subject to approval of the authority having jurisdiction, a ladder device as specified herein may be used in lieu of a fire escape when the construction feature or the location of the building on the property cause the installation of a fire escape to be impractical.

    313.3 Stair construction. All stairs shall have a minimum run of 9 inches (229 mm) and a maximum rise of 8 inches (203 mm) and a minimum width exclusive of handrails of 30 inches (762 mm). Every stairway shall have at least one handrail. A landing having a minimum horizontal dimension of 30 inches (762 mm) shall be provided at each point of access to the stairway.

    313.4 Interior stairways. Every interior stairway shall be enclosed with walls of not less than 1-hour fire-resistive construction. Where existing partitions form part of a stairwell enclosure, wood lath and plaster in good condition will be acceptable in lieu of 1-hour fire- resistive construction. Doors to such enclosures shall be protected by a self-closing door equivalent to a solid wood door with a thickness of not less than 1 [3] / 4 inches (44.5 mm).

    Enclosures shall include all landings between flights and any corridors, passageways or public rooms necessary for continuous exit to the exterior of the buildings. The stairway need not be enclosed in a continuous shaft if cut off at each story by the fire-resistive construction required by this subsection for stairwell enclosures. Enclosures shall not be required if an automatic sprinkler system is provided for all portions of the building except bedrooms, apartments and rooms accessory thereto. Interior stairs and vertical openings need not be enclosed in two-story buildings.

    313.5 Exterior stairways. Exterior stairways shall be noncombustible or of wood of not less than 2-inch (51 mm) nominal thickness with solid treads and risers.

    313.6 Fire escapes, exit ladder devices. Fire escapes may be used as one means of egress if the pitch does not exceed 60 degrees, the width is not less than 18 inches (457 mm), the treads are not less than 4 inches (102 mm) wide, and they extend to the ground or are provided with counterbalanced stairs reaching to the ground. Access shall be by an opening having a minimum dimension of 29 inches (737 mm) when open. The sill shall not be more than 30 inches (762 mm) above the floor and landing.

Frequently asked questions

Can I use a ladder instead of a fire escape for every historic building?

Not always. The CHBC allows ladder devices in some situations, but there are limits (for example occupant load, building height, and the CHBC’s ladder strength and dimension rules). For multi‑story buildings (four or more stories) the escape must extend to the roof or use an approved gooseneck ladder and must meet the ladder specs in § 8-502.6 .

Are openings near the fire escape required to be fire‑rated?

Yes. Openings within 10 feet of a fire escape must be protected by 3/4‑hour fire assemblies per § 8-502.6; consult the enforcing agency for equivalencies where sprinklers are provided since the uploaded CHBC text does not show a specific sprinkler exception within § 8-502.6 itself .

How high can the lowest balcony be above grade?

The lowest balcony shall be no more than 18 feet above the ground; if higher, the fire escape must extend to the ground or be provided with counterbalanced stairs — § 8-502.6 item 7 .

Do railings and handrails need to be engineered for horizontal loads?

Yes. Railings must resist 50 pounds per lineal foot horizontally, and ladders must resist 100 pounds on a rung where specified — both are required in § 8-502.6 .

Who decides if a proposed fire escape length or ladder device is acceptable?

The building official: the CHBC limits the length of fire escapes and exit ladder devices based on products listed by a recognized testing laboratory and approval by the building official (§ 8-502.6 item 6) .

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Stairs, fire escapes and exit ladder devices

California Historical Building Code