CRC · California Residential Code

What are the CRC requirements for means of egress, stairs, handrails, guards and window fall protection?

Summary: This explains the California Residential Code rules you must follow for safe exits: ramps and stairs must have required landings, slopes and handrails; open edges above 30 inches need guards at 42 inches (34 inches on open stair sides); egress windows must meet net opening and dimension rules; windows with low sills above deep grade must either block a 4‑inch sphere or have compliant fall‑prevention devices. All quoted requirements point to CRC **§ R318**, **§ R319**, **§ R320** and **§ R321**.

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Last reviewed: July 6, 2026

What the code requires — 2-4 sentences

In plain English: provide safe, continuous egress routes (doors, ramps, stairs and landings), install continuous handrails where required, fit guards at open sides above a threshold height, and protect low‑sill windows above grade so people can’t fall out. The controlling California Residential Code sections are § R318, § R319, § R320 and § R321.

The single most important rule: make sure egress paths are usable (landings and clearances), stairs and ramps have required handrails, open edges are guarded at the code heights, and windows that could let someone fall comply with the opening/ device rules in §§ R318–R321.

Requirements in detail

Means of egress (high‑level) — § R318

  • Provide required exits, clear width, landings and accessible routes as the chapter requires; ramps and stairs serving egress must meet specific dimensional and landing rules in § R318.8 and the stair subsections.
  • Ramps serving an egress door are limited to a maximum slope of 1:12 (8.3%); other ramps 1:8 (12.5%) where allowed. § R318.8.1.
  • Ramps require a landing at top and bottom and where direction changes; landing depth in direction of slope must be at least 36 inches. § R318.8.2.

Stairs (selected CRC items in R318) — § R318.7 (selected subsections retrieved)

  • The CRC prohibits use of alternating tread devices and ship’s ladders as the primary means of egress except in tightly limited conditions; when permitted they have prescribed tread, projection and riser rules and a minimum clear width of 20 inches at and below handrails. § R318.7.12, § R318.7.13.
  • Ship’s ladders and alternating‑tread devices: minimum tread depths not less than 5 in., projected tread + nosing min 8-1/2 in., and max riser ~9-1/2 in. where allowed. § R318.7.12.1, § R318.7.13.1.

Note: The CRC subsections covering conventional stair riser/tread and nosing dimensions (common numeric limits) were not returned in the retrieved excerpts for § R318.7.5 in my search results; do not rely on this article for those exact numbers — consult § R318.7 in the CRC text for the full stair‑dimension table.

Handrails — § R320 (key rules)

  • Continuity: Handrails must be continuous for the full length of the flight (from above the top nosing to above the lowest nosing). § R320.5.
  • Returns / ends: Handrail ends must be returned to a wall, guard, or walking surface; returns must not create a > 1/4 inch gap from the adjacent wall. § R320.5.
  • Grip size / graspability: Two types allowed:
    • Type I circular: outside diameter 1-1/4 in. to 2 in.; non‑circular: perimeter 4 in. to 6-1/4 in. and cross‑section not more than 2-1/4 in. § R320.6 (1).
    • Type II (larger profiles) must include a finger recess meeting specified depth/width/vertical positions (detailed in § R320.6 (2)).
  • Ramps: handrails are required on at least one side of ramps exceeding 1:12 egress slope per § R318.8.3 and must comply with § R320.

Guards and window fall protection — § R321 (key rules)

  • Where guards are required: at open‑sided walking surfaces (floors, stairs, ramps, landings) that are located more than 30 inches measured vertically to the floor or grade below at any point within 36 inches horizontally to the open edge. § R321.1.1.
  • Guard height: required guards are not less than 42 inches high measured vertically above the adjacent walking surface (or the line connecting nosings on stairs). § R321.1.2.
    • Exception (stairs): guards on the open side of stairs may be not less than 34 inches measured from the line connecting the nosings; if the top of the guard serves as a handrail on stairs, the top of the guard must be 34 in. to 38 in. above the nosings. § R321.1.2 exceptions.
  • Opening limitations: guards must not have openings that permit a 4‑inch diameter sphere to pass from the walking surface to the required guard height. § R321.1.3.
    • Exceptions: triangular stair‑side openings (formed by riser, tread, bottom rail) may be sized to prevent passage of a 6‑inch sphere; guards on open side of stairs have a modified sphere limit of 4‑3/8 inches. § R321.1.3 exceptions.
  • Window fall protection — § R321.2:
    • In dwelling units where the bottom of the clear opening of an operable window is < 24 inches above the finished floor and the exterior grade below is > 72 inches, the operable window must either:
      1. Not allow a 4‑inch diameter sphere to pass through in its largest opened position; or
      2. Be provided with an approved window opening control device / fall prevention device that complies with ASTM F2090. § R321.2.1.
    • If an operable window also serves as a required emergency escape opening, any control device must, after release, not reduce the net clear opening below the areas/dimensions required in § R319.2.1 and § R319.2.2. § R321.2.2.

Emergency escape & rescue openings (egress windows) — § R319 (required sizes)

  • Where required: every sleeping room, basements with sleeping rooms, habitable attics, and rooms open to sleeping lofts must have at least one operable emergency escape and rescue opening. § R319.1.
  • Minimum net clear opening area: 5.7 sq ft (0.530 m2). Exception: grade‑floor openings may be 5.0 sq ft. § R319.2.1.
  • Minimum net clear dimensions: height 24 inches, width 20 inches (the opening dimensions must be achieved by normal operation). § R319.2.2.
  • Maximum sill height: bottom of clear opening not more than 44 inches above the floor. § R319.2.3.
  • Under‑deck openings: openings under decks/porches must be fully openable and provide a path at least 36 in. × 36 in. to the yard/court. § R319.2.4.
  • Operational constraints: egress openings must be operable from inside without keys/tools; ASTM F2090 devices are permitted if placed so release is within 70 in. of finished floor. § R319.1.1.

Table — Decision‑relevant dimensions and where to find them in the CRC

Item Key value(s) Code Reference
Guard required (vertical/horizontal trigger) > 30 in. vertically within 36 in. horizontally § R321.1.1
Guard height (general) 42 in. above walking surface § R321.1.2
Guard height (open side of stairs) 34 in. (measured from line connecting nosings) § R321.1.2 exception
Guard opening limit 4‑inch sphere § R321.1.3
Stair triangular openings 6‑inch sphere allowed (triangle exception) § R321.1.3 exception
Ramp slope (egress door) 1:12 (8.3%) max § R318.8.1
Ramp slope (other) 1:8 (12.5%) max § R318.8.1
Ramp landing depth 36 in. min (in direction of slope) § R318.8.2
Handrail continuity Continuous for full flight; returns required § R320.5
Handrail grip size (Type I) 1-1/4 in. – 2 in. diameter (circular) § R320.6.1
Handrail non‑circular perimeter 4 in. – 6-1/4 in. § R320.6.1
Egress window net clear opening 5.7 sq ft (unit); 5.0 sq ft for grade‑floor § R319.2.1
Egress window min height / width 24 in. high × 20 in. wide § R319.2.2
Egress window sill max height 44 in. above room floor § R319.2.3
Window fall protection trigger Bottom clear opening < 24 in. above finished floor and exterior grade > 72 in. below § R321.2.1
Window sphere protection 4‑inch sphere requirement OR ASTM F2090 device § R321.2.1
Window control device + egress Control device may not reduce net clear opening below § R319.2.1/2 § R321.2.2

Exceptions & special cases

  • Screens are not guards. Insect screening does not substitute for a guard. § R321.1.1.
  • Stair guards can be lower. Guards on open stair sides may be 34 in. rather than 42 in. (measure from nosings); when guard top doubles as handrail on stairs the top must be 34–38 in. from nosings. § R321.1.2 exceptions.
  • Alternating tread devices and ship’s ladders are allowed only in specific small‑space conditions and are not a general substitute for compliant stairs; when used they must meet their own tread/riser and width minimums. § R318.7.12 – R318.7.13.
  • Basement sleeping rooms have some exemptions from emergency openings where alternative egress or sprinklers are provided — see § R319.1 exceptions.

Common mistakes

  • Measuring guard height to the wrong reference: guard height is measured vertically above the adjacent walking surface (or the line connecting nosings on stairs) — not from the top of a deck board or handrail cap unless that is the walking surface. § R321.1.2.
  • Treating insect screen or jalousie slats as a guard — they are explicitly excluded. § R321.1.1.
  • Installing window opening control devices that prevent required egress by reducing net clear opening area below § R319.2.1/2 — control devices are allowed only if, after release, the opening still meets the egress dimensions. § R321.2.2.
  • Using a handrail profile that is too large to grasp safely (not meeting Type I or Type II graspability) or leaving handrail ends unreturned. § R320.6, § R320.5.

Worked example

Scenario: second‑floor balcony and a bedroom window

  • Balcony walking surface is 40 inches above the exterior grade within 24 inches of the open edge. Does it need a guard? Yes — it is > 30 in. vertical within 36 in. horizontal, so a guard is required. § R321.1.1.
  • Required guard height: 42 in. above the adjacent walking surface (because it’s an elevated walking surface), so the balcony guard must be 42 in. high. § R321.1.2.
  • If the guard top is used as the handrail on an open stair on that side, and the measurement is from the nosings, the top can be 34–38 in. from the nosing line per the stair exception. § R321.1.2.

Window example:

  • Bedroom has an operable window with bottom of clear opening 20 in. above finished floor and the exterior grade below is 8 feet (96 in.) below the window bottom (> 72 in.). This matches the window fall‑protection trigger in § R321.2.1.
  • Options: (a) fit the operable window so that in its largest open position it will not allow a 4‑inch sphere to pass; or (b) install an ASTM F2090 window opening control/fall‑prevention device (but if the window is also the required emergency escape opening, the device must not reduce the net clear opening below § R319.2.1/2 — i.e., 5.7 sq ft and 24 in. × 20 in. minimum). § R321.2.1 and § R321.2.2.

Related provisions (CRC sections you should check)

  • § R318 — Means of egress (ramps, stairs, landings, vertical egress).
  • § R319 — Emergency escape and rescue openings (egress windows: area, dimensions, wells).
  • § R320 — Handrail requirements (continuity, grip size).
  • § R321 — Guards and window fall protection (where guards are required, heights, opening limits, window protection).
  • § R318.8 — Ramp slope, landings and ramp handrail triggers.
  • See also: § R324 (glazing / safety glazing where applicable) and § R325 (lighting/illumination requirements for stairs) as applicable in Chapter 3 (these were indexed in the CRC).

Code references

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

  • CRC § 0.01 High relevance — show source text
    1. Type II. Handrails with a perimeter greater than 6 [1] / 4 inches (160 mm) shall have a graspable finger recess area on both sides of the profile. The finger recess shall begin within [3] / 4 inch (19 mm) measured vertically from the tallest portion of the profile and have a depth of not less than [5] / 16 inch (8 mm) within [7] / 8 inch (22 mm) below the widest portion of the profile. This required depth shall continue for not less than [3] / 8 inch (10 mm) to a level that is not less than 1 [3] / 4 inches (45 mm) below the tallest portion of the profile. The width of the handrail above the recess shall be not less than 1 [1] / 4 inches (32 mm) and not more than 2 [3] / 4 inches (70 mm). Edges shall have a radius of not less than 0.01 inch (0.25 mm).

    R320.7 Exterior plastic composite handrails. Plastic composite exterior handrails shall also comply with the requirements of Section R507.2.2.

    SECTION R321—GUARDS AND WINDOW FALL PROTECTION

    R321.1 Guards. Guards shall be provided in accordance with Sections R321.1.1 through R321.1.4.

    R321.1.1 Where required. Guards shall be provided for those portions of open-sided walking surfaces, including floors, stairs, ramps and landings that are located more than 30 inches (762 mm) measured vertically to the floor or grade below at any point within 36 inches (914 mm) horizontally to the edge of the open side. Insect screening shall not be considered as a guard.

    R321.1.2 Height. Required guards at open-sided walking surfaces, including stairs, porches, balconies or landings, shall be not less than 42 inches (1067 mm) in height as measured vertically above the adjacent walking surface or the line connecting the nosings.

    Exceptions:

    1. Guards on the open sides of stairs shall have a height of not less than 34 inches (864 mm) measured vertically from a line connecting the nosings.

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    1. Where the top of the guard serves as a handrail on the open sides of stairs, the top of the guard shall be not less than 34 inches (864 mm) and not more than 38 inches (965 mm) as measured vertically from a line connecting the nosings.

    R321.1.3 Opening limitations. Required guards shall not have openings from the walking surface to the required guard height that allow passage of a sphere 4 inches (102 mm) in diameter.

    Exceptions:

    1. The triangular openings at the open side of stair, formed by the riser, tread and bottom rail of a guard, shall not allow passage of a sphere 6 inches (153 mm) in diameter.
    2. Guards on the open side of stairs shall not have openings that allow passage of a sphere 4 [3] / 8 inches (111 mm) in diameter.

    R321.1.4 Exterior plastic composite guards. Plastic composite exterior guards shall comply with the requirements of Section R507.2.2.

  • CRC § 1.2 High relevance — show source text

    R321.1.2 Height. Required guards at open-sided walking surfaces, including stairs, porches, balconies or landings, shall be not less than 42 inches (1067 mm) in height as measured vertically above the adjacent walking surface or the line connecting the nosings.

    Exceptions:

    1. Guards on the open sides of stairs shall have a height of not less than 34 inches (864 mm) measured vertically from a line connecting the nosings.

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    1. Where the top of the guard serves as a handrail on the open sides of stairs, the top of the guard shall be not less than 34 inches (864 mm) and not more than 38 inches (965 mm) as measured vertically from a line connecting the nosings.

    R321.1.3 Opening limitations. Required guards shall not have openings from the walking surface to the required guard height that allow passage of a sphere 4 inches (102 mm) in diameter.

    Exceptions:

    1. The triangular openings at the open side of stair, formed by the riser, tread and bottom rail of a guard, shall not allow passage of a sphere 6 inches (153 mm) in diameter.
    2. Guards on the open side of stairs shall not have openings that allow passage of a sphere 4 [3] / 8 inches (111 mm) in diameter.

    R321.1.4 Exterior plastic composite guards. Plastic composite exterior guards shall comply with the requirements of Section R507.2.2.

    R321.2 Window fall protection. Window fall protection shall be provided in accordance with Sections R321.2.1 and R321.2.2.

    R321.2.1 Window opening height. In dwelling units, where the bottom of the clear opening of an operable window opening is located less than 24 inches (610 mm) above the finished floor and greater than 72 inches (1829 mm) above the finished grade or other surface below on the exterior of the building, the operable window shall comply with one of the following:

    1. Operable window openings will not allow a 4-inch-diameter (102 mm) sphere to pass through where the openings are in their largest opened position.
    2. Operable windows are provided with window opening control devices or fall prevention devices that comply with ASTM F2090.

    R321.2.2 Emergency escape and rescue openings. Where an operable window serves as an emergency escape and rescue opening, a window opening control device or fall prevention device, after operation to release the control device or fall prevention device allowing the window to fully open, shall not reduce the net clear opening area of the window unit to less than the area required by Sections R319.2.1 and R319.2.2.

    SECTION R322—ACCESSIBILITY

    R322.1 Dwelling units or sleeping units. Dwelling units in a building consisting of three or more dwelling units or four or more condo- minium units shall meet the requirements of the California Building Code Chapter 11A. Covered Multifamily Dwellings include but are not limited to dwelling units listed in Section 1.8.2.1.2. Dwelling units within a single structure separated by firewalls do not constitute sepa- rate buildings.

  • CRC § 1012.6.3 High relevance — show source text

    MEANS OF EGRESS

    [BE] 1012.6.3 Length. The landing length shall be 60 inches (1525 mm) minimum.

    Exceptions:

    1. In Group R-2 and R-3 individual dwelling and sleeping units that are not required to be Accessible units, Type A units or Type B units in accordance with Chapter 11A or 11B of the California Building Code, landings are permitted to be 36 inches (914 mm) minimum.

    2. Where the ramp is not a part of an accessible route, the length of the landing shall not be required to be more than 48 inches (1219 mm) in the direction of travel.

    [BE] 1012.6.4 Change in direction. Where changes in direction of travel occur at landings provided between ramp runs, the landing shall be 60 inches by 60 inches (1524 mm by 1524 mm) minimum.

    Exception: In Group R-2 and R-3 individual dwelling or sleeping units that are not required to be Accessible units, Type A units or Type B units in accordance with Section 1108 of the California Building Code, landings are permitted to be 36 inches by 36 inches (914 mm by 914 mm) minimum.

    [BE] 1012.6.5 Doorways. Where doorways are located adjacent to a ramp landing, maneuvering clearances required by ICC A117.1 are permitted to overlap the required landing area.

    [BE] 1012.7 Ramp construction. Ramps shall be built of materials consistent with the types permitted for the type of construction of the building, except that wood handrails shall be permitted for all types of construction.

    [BE] 1012.7.1 Ramp surface. The surface of ramps shall be of slip-resistant materials that are securely attached.

    [BE] 1012.7.2 Outdoor conditions. Outdoor ramps and outdoor approaches to ramps shall be designed so that water will not accumulate on walking surfaces.

    [BE] 1012.8 Handrails. Ramps with a rise greater than 6 inches (152 mm) shall have handrails on both sides. Handrails shall comply with Section 1014.

    [BE] 1012.9 Guards. Guards shall be provided where required by Section 1015 and shall be constructed in accordance with Section 1015.

    [BE] 1012.10 Edge protection. Edge protection complying with Section 1012.10.1 or 1012.10.2 shall be provided on each side of ramp runs and at each side of ramp landings.

    Exceptions:

    1. Edge protection is not required on ramps that are not required to have handrails, provided that they have flared sides that comply with the ICC A117.1 curb ramp provisions.

    2. Edge protection is not required on the sides of ramp landings serving an adjoining ramp run or stairway.

    3. Edge protection is not required on the sides of ramp landings having a vertical dropoff of not more than [1] / 2 inch (12.7 mm) within 10 inches (254 mm) horizontally of the required landing area.

  • CRC § 12.7 High relevance — show source text

    1. Any stairway replacing an existing stairway within a space where the pitch or slope cannot be reduced because of existing construction shall not be required to comply with the maximum riser height and minimum tread depth requirements.

    2. Existing corridor walls constructed on both sides of wood lath and plaster in good condition or [1] / 2 -inch-thick (12.7 mm) gypsum wallboard shall be permitted. Such walls shall either terminate at the underside of a ceiling of equivalent construction or extend to the underside of the floor or roof next above.

    3. Existing corridor doorways, transoms and other corridor openings shall comply with the requirements in Sections 804.7.1, 804.7.2 and 804.7.3.

    4. Existing dead-end corridors shall comply with the requirements in Section 804.8.

    5. An operable window complying with Section 1011.5.6 shall be accepted as an emergency escape and rescue opening.

    6. In Group R-2.1 and I-2 facilities, required guards enclosing the occupiable roof areas shall be permitted to be greater than 48 inches (1219 mm) above the surface of the occupiable roof where the occupants, because of clinical needs, require restraint or containment as part of a function of a psychiatric or cognitive treatment area.

    1011.5.2 Means of egress for change of use to an equal or lower-hazard category. Where a change of occupancy classification is made to an equal or lesser-hazard category (higher number) as shown in Table 1011.5, existing elements of the means of egress shall comply with the requirements of Section 905 for the new occupancy classification. Newly constructed or configured means of egress shall comply with the requirements of Chapter 10 of the California Building Code .

    Exceptions:

    1. Any stairway replacing an existing stairway within a space where the pitch or slope cannot be reduced shall not be required to comply with the maximum riser height and minimum tread depth requirements.
    2. In Group R-2.1 and I-2 facilities, required guards enclosing the occupiable roof areas shall be permitted to be greater than 48 inches (1219 mm) above the surface of the occupiable roof where the occupants, because of clinical needs, require restraint or containment as part of a function of a psychiatric or cognitive treatment area.

    1011.5.3 Egress capacity. Egress capacity shall meet or exceed the occupant load as specified in the California Building Code for the new occupancy.

    1011.5.4 Handrails. Existing stairways shall comply with the handrail requirements of Section 804.13.

    1011.5.5 Guards. Existing guards shall comply with the requirements in Section 804.12.

    1011.5.6 Existing emergency escape and rescue openings. Where a change of occupancy would require an emergency escape and rescue opening in accordance with Section 1031 of the California Building Code, operable windows serving as the emergency escape and rescue opening shall comply with the following:

    1. An existing operable window shall provide a minimum net clear opening of 4 square feet (0.38 m [2] ) with a minimum net clear opening height of 22 inches (559 mm) and a minimum net clear opening width of 20 inches (508 mm).
    2. A replacement window where such window complies with both of the following: 2.1. The replacement window meets the size requirements in Item 1. 2.2. The replacement window is the manufacturer’s largest standard size window that will fit within the existing frame or existing rough opening.
  • CRC § 1015.5 High relevance — show source text

    [BE] 1015.5 Screen porches. Porches and decks that are enclosed with insect screening shall be provided with guards where the walking surface is located more than 30 inches (762 mm) above the floor or grade below.

    [BE] 1015.6 Mechanical equipment, systems and devices. Guards shall be provided where various components that require service are located within 10 feet (3048 mm) of a roof edge or open side of a walking surface and such edge or open side is located more than 30

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    MEANS OF EGRESS

    inches (762 mm) above the floor, roof or grade below. The guard shall extend not less than 30 inches (762 mm) beyond each end of such components. The guard shall be constructed so as to prevent the passage of a sphere 21 inches (533 mm) in diameter.

    Exception: Guards are not required where personal fall arrest anchorage connector devices that comply with ANSI/ASSE Z359.1 are installed.

    [BE] 1015.7 Roof access. Guards shall be provided where the roof hatch opening is located within 10 feet (3048 mm) of a roof edge or open side of a walking surface and such edge or open side is located more than 30 inches (762 mm) above the floor, roof or grade below. The guard shall extend not less than 30 inches (762 mm) beyond each end of the hatch parallel to the roof edge. The guard shall be constructed so as to prevent the passage of a sphere 21 inches (533 mm) in diameter.

    Exception: Guards are not required where personal fall arrest anchorage connector devices that comply with ANSI/ASSE Z359.1 are installed.

    [BE] 1015.8 Window openings. Windows in Group R-2 and R-3 buildings including dwelling units, where the bottom of the clear opening of an operable window is located less than 36 inches (914 mm) above the finished floor and more than 72 inches (1829 mm) above the finished grade or other surface below on the exterior of the building, shall comply with one of the following:

    1. Where the bottom of the clear opening of the window is located more than 72 inches (1829 mm) and less than 75 feet (22 860 mm) above the finished grade or other surface below on the exterior of the building, the window shall comply with one of the following: 1.1. Operable windows where the openings will not allow a 4-inch-diameter (102 mm) sphere to pass through the opening when the window is in its largest opened position, provided that the opening is not required for emer gency escape or rescue. 1.2. Operable windows where the openings are provided with window fall prevention devices that comply with ASTM F2090.
  • CRC § 3-60 High relevance — show source text

    R315 Sleeping Lofts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-60

    R316 Habitable Attics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-61

    R317 Garages and Carports. . . . . . . . . . . . . . . . . . . . . . . . . . 3-61

    R318 Means of Egress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-62

    R319 Emergency Escape and Rescue Openings . . . . . . . . 3-65

    R320 Handrails . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-67

    R321 Guards and Window Fall Protection . . . . . . . . . . . . . 3-67

    R322 Accessibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-68

    R323 Elevators and Platform Lifts . . . . . . . . . . . . . . . . . . . . 3-68

    R324 Glazing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-68

    R325 Light, Ventilation and Heating . . . . . . . . . . . . . . . . . . 3-72

    R326 Sanitation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-73

    R327 Toilet, Bath and Shower Spaces. . . . . . . . . . . . . . . . . 3-73

    R328 Aging-in-Place Design and Fall Prevention . . . . . . . . 3-73

    R329 Solar Energy Systems . . . . . . . . . . . . . . . . . . . . . . . . . . 3-74

    R330 Energy Storage Systems . . . . . . . . . . . . . . . . . . . . . . . 3-76

    R331 Stationary Engine Generators. . . . . . . . . . . . . . . . . . . 3-79

    R332 Stationary Fuel Cell Power Systems . . . . . . . . . . . . . 3-79

    R333 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-79

    R334 Construction Waste Reduction, Disposal and Recycling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-79

    R335 Special Provisions for Licensed 24-Hour Care Facilities in a Group R-3.1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-79

  • CRC § 6.4 High relevance — show source text

    R320.5 Continuity. Handrails shall be continuous for the full length of the flight, from a point directly above the nosing of the landing at the top of the flight to a point directly above the lowest nosing of the flight. Handrails where required for ramps shall be continuous for the full length of the ramp. A handrail end shall be returned continuous to itself or toward a wall, guard or walking surface. Handrail returns shall not form a gap more than [1] / 4 inch (6.4 mm) from the adjacent wall.

    Exceptions:

    1. Handrail continuity shall be permitted to be interrupted by a newel post at a turn in a flight with winders, at a landing, or over the lowest tread.

    2. A volute, turnout or starting easing shall be allowed to terminate over the lowest tread.

    R320.6 Grip size. Required handrails shall be of one of the following types or provide equivalent graspability.

    1. Type I. Handrails with a circular cross section shall have an outside diameter of not less than 1 [1] / 4 inches (32 mm) and not greater than 2 inches (51 mm). If the handrail is not circular, it shall have a perimeter of not less than 4 inches (102 mm) and not greater than 6 [1] / 4 inches (160 mm) and a cross section of not more than 2 [1] / 4 inches (57 mm). Edges shall have a radius of not less than 0.01 inch (0.25 mm).
    2. Type II. Handrails with a perimeter greater than 6 [1] / 4 inches (160 mm) shall have a graspable finger recess area on both sides of the profile. The finger recess shall begin within [3] / 4 inch (19 mm) measured vertically from the tallest portion of the profile and have a depth of not less than [5] / 16 inch (8 mm) within [7] / 8 inch (22 mm) below the widest portion of the profile. This required depth shall continue for not less than [3] / 8 inch (10 mm) to a level that is not less than 1 [3] / 4 inches (45 mm) below the tallest portion of the profile. The width of the handrail above the recess shall be not less than 1 [1] / 4 inches (32 mm) and not more than 2 [3] / 4 inches (70 mm). Edges shall have a radius of not less than 0.01 inch (0.25 mm).

    R320.7 Exterior plastic composite handrails. Plastic composite exterior handrails shall also comply with the requirements of Section R507.2.2.

    SECTION R321—GUARDS AND WINDOW FALL PROTECTION

    R321.1 Guards. Guards shall be provided in accordance with Sections R321.1.1 through R321.1.4.

    R321.1.1 Where required. Guards shall be provided for those portions of open-sided walking surfaces, including floors, stairs, ramps and landings that are located more than 30 inches (762 mm) measured vertically to the floor or grade below at any point within 36 inches (914 mm) horizontally to the edge of the open side. Insect screening shall not be considered as a guard.

  • CRC § 1015.5 High relevance — show source text

    7. In lifeguard towers not open to the public, guards shall not have openings which allow passage of a sphere 21 inches (533 mm) in diameter.

    1015.5 Screen porches. Porches and decks that are enclosed with insect screening shall be provided with guards where the walking surface is located more than 30 inches (762 mm) above the floor or grade below.

    1015.6 Mechanical equipment, systems and devices. Guards shall be provided where various components that require service are located within 10 feet (3048 mm) of a roof edge or open side of a walking surface and such edge or open side is located more than 30 inches (762 mm) above the floor, roof or grade below. The guard shall extend not less than 30 inches (762 mm) beyond each end of such components. The guard shall be constructed so as to prevent the passage of a sphere 21 inches (533 mm) in diameter.

    Exception: Guards are not required where personal fall arrest anchorage connector devices that comply with ANSI/ASSE Z 359.1 are installed.

    1015.7 Roof access. Guards shall be provided where the roof hatch opening is located within 10 feet (3048 mm) of a roof edge or open side of a walking surface and such edge or open side is located more than 30 inches (762 mm) above the floor, roof or grade below. The guard shall extend not less than 30 inches (762 mm) beyond each end of the hatch parallel to the roof edge. The guard shall be constructed so as to prevent the passage of a sphere 21 inches (533 mm) in diameter.

    Exception: Guards are not required where personal fall arrest anchorage connector devices that comply with ANSI/ASSE Z 359.1 are installed.

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    1015.8 Window openings. Windows in Group R-1, R-2 and R-3 buildings including dwelling units, where the bottom of the clear opening of an operable window is located less than 36 inches (914 mm) above the finished floor and more than 72 inches (1829 mm) above the finished grade or other surface below on the exterior of the building, shall comply with one of the following:

    1. Where the bottom of the clear opening of the window is located more than 72 inches (1829 mm) and less than 75 feet (22 860 mm) above the finished grade or other surface below on the exterior of the building, the window shall comply with one of the following: 1.1. Operable windows where the openings will not allow a 4-inch-diameter (102 mm) sphere to pass through the opening when the window is in its largest opened position, provided that the opening is not required for emer gency escape or rescue. 1.2. Operable windows where the openings are provided with window fall prevention devices that comply with ASTM F2090.
  • CRC § 3-33 High relevance — show source text

    R304 Protection of Wood and Wood-Based Products

    Against Decay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-33

    R305 Protection Against Subterranean Termites. . . . . . . 3-35

    R306 Flood-Resistant Construction. . . . . . . . . . . . . . . . . . . 3-36

    R307 Storm Shelters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-40

    R308 Site Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-40

    R309 Automatic Sprinkler Systems . . . . . . . . . . . . . . . . . . . 3-41

    R310 Smoke Alarms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-54

    R311 Carbon Monoxide Alarms. . . . . . . . . . . . . . . . . . . . . . . 3-58

    R312 Minimum Room Areas . . . . . . . . . . . . . . . . . . . . . . . . . 3-59

    R313 Ceiling Height . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-59

    R314 Mezzanines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-60

    R315 Sleeping Lofts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-60

    R316 Habitable Attics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-61

    R317 Garages and Carports. . . . . . . . . . . . . . . . . . . . . . . . . . 3-61

    R318 Means of Egress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-62

    R319 Emergency Escape and Rescue Openings . . . . . . . . 3-65

    R320 Handrails . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-67

    R321 Guards and Window Fall Protection . . . . . . . . . . . . . 3-67

    R322 Accessibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-68

    R323 Elevators and Platform Lifts . . . . . . . . . . . . . . . . . . . . 3-68

    R324 Glazing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-68

  • CRC § 2.1.5 High relevance — show source text

    BB104.2.1.5 Landing platforms. The top tread and riser of stairways accessing lofts shall be constructed as a landing platform where the loft ceiling height is less than 6 feet 2 inches (1880 mm) where the stairway meets the loft. The landing platform shall be not less than 20 inches (508 mm) in width and in depth measured horizontally from and perpendicular to the nosing of the landing platform. The landing platform riser height to the loft floor shall be not less than 16 inches (406 mm) and not greater than 18 inches (457 mm).

    BB104.2.1.6 Handrails. Handrails shall comply with Section R318.7.8.

    BB104.2.1.7 Stairway guards. Guards at open sides of stairways, landings and landing platforms shall comply with Section R321.1.

    BB104.2.2 Ladders. Ladders accessing lofts shall comply with Sections BB104.2.1 and BB104.2.2.2.

    BB104.2.2.1 Size and capacity. Ladders accessing lofts shall have a rung width of not less than 12 inches (305 mm), and 10inch (254 mm) to 14-inch (356 mm) spacing between rungs. Ladders shall be capable of supporting a 300-pound (136 kg) load on any rung. Rung spacing shall be uniform within [3] / 8 inch (9.5 mm).

    BB104.2.2.2 Incline. Ladders shall be installed at 70 to 80 degrees from horizontal.

    BB104.2.3 Alternating tread devices. Alternating tread devices accessing lofts shall comply with Sections R318.7.12.1 and R318.7.12.2. The clear width at and below the handrails shall be not less than 20 inches (508 mm).

    BB104.2.4 Ship’s ladders. Ship’s ladders accessing lofts shall comply with Sections R318.7.13.1 and R318.7.13.2. The clear width at and below handrails shall be not less than 20 inches (508 mm).

    BB104.2.5 Loft guards. Loft guards shall be located along the open sides of lofts. Loft guards shall be not less than 36 inches (914 mm) in height or one-half of the clear height to the ceiling, whichever is less. Loft guards shall comply with Section R321.1.3 and Table R301.5 for their components.

    SECTION BB105—EMERGENCY ESCAPE AND RESCUE OPENINGS

    BB105.1 General. Tiny houses shall meet the requirements of Section R319 for emergency escape and rescue openings.

    Exception: Egress roof access windows in lofts used as sleeping rooms shall be deemed to meet the requirements of Section R319 where installed such that the bottom of the opening is not more than 44 inches (1118 mm) above the loft floor, provided the egress roof access window complies with the minimum opening area requirements of Section R319.2.1.

    �

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    BC RESERVED

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  • CRC § 8.1 High relevance — show source text

    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.

    BO105.8.5 Stairway illumination. Stairways within the work area shall be provided with illumination in accordance with Section R325.7.

    BO105.8.6 Handrails and guards. If a stair or any portion of a stair is altered, a handrail and guard, where required, shall be provided in accordance with Sections R318 and R320.

    SECTION BO106—ADDITION

    BO106.1 General. Where existing buildings with the addition are within the scope of this code, additions shall comply with this section and other applicable provisions of this code for new construction or as permitted by this appendix. Engineered design in accordance with Section R301.1.3 shall be permitted to meet the requirements of this section.

    BO106.2 Structure for horizontal additions. Where an addition involves new construction attached to an existing building, the new construction shall meet all of the structural requirements of this code for new construction. Alterations to the existing building shall comply with the requirements governing alterations within this code. In wood light-frame additions, connection of the structural components shall be permitted to be provided using wall top plates and addition studs that abut the existing building. Wall top plates shall be lapped and spliced in accordance with Section R602.3.2. Abutting studs shall be fastened in accordance with Table R602.3(1).

    Exception: The addition structure shall be permitted to be connected to the existing building in accordance with accepted engineering practice.

    BO106.3 Structure for vertical additions. Where an addition involves new construction that adds a story to any part of the existing building or vertically increases the height of any part of the existing building, the new construction and the existing building together shall be shown to comply with, or altered to comply with, all of the structural requirements of this code for new construction.

    Exception: Where the new structure and the existing structure together are evaluated in accordance with accepted engineering practice and are shown to be sufficient to support the combined loads from the new structure and existing structure, no structural alterations are required.

    SECTION BO107—RELOCATED BUILDINGS

  • CRC § 1014.10 Medium relevance — show source text

    In Group I-2 occupancy ramps required for exit access shall not be less than 8 ft in width and handrails are permitted to protrude 3 [ 1] / 2 inches from the wall on both sides. Ramps used as exits and stairways used for the movement of bed and litter patients, the clear width between handrails shall be 44 inches (1118 mm) minimum.

    [HCD 1-AC] In addition, projections shall comply with Chapter 11A, when applicable.

    1014.10 Intermediate handrails. Stairways shall have intermediate handrails located in such a manner that all portions of the stairway minimum width or required capacity are within 30 inches (762 mm) of a handrail. On monumental stairs, handrails shall be located along the most direct path of egress travel.

    SECTION 1015—GUARDS

    1015.1 General. Guards shall comply with the provisions of Sections 1015.2 through 1015.7. Operable windows with sills located more than 72 inches (1829 mm) above finished grade or other surface below shall comply with Section 1015.8.

    1015.2 Where required. Guards shall be located along open-sided walking surfaces, such as mezzanines, equipment platforms, aisles, stairs, ramps and landings, that are located more than 30 inches (762 mm) measured vertically to the floor or grade below at any point within 36 inches (914 mm) horizontally to the edge of the open side and at the perimeter of occupiable roofs. Guards shall be adequate in strength and attachment in accordance with Section 1607.9.

    Exceptions: Guards are not required for the following locations:

    1. On the loading side of loading docks or piers.
    2. On the audience side of stages and raised platforms, including stairs leading up to the stage and raised platforms.
    3. On raised stage and platform floor areas, such as runways, ramps and side stages used for entertainment or presentations.
    4. At vertical openings in the performance area of stages and platforms.
    5. At elevated walking surfaces appurtenant to stages and platforms for access to and utilization of special lighting or equipment.
    6. Along vehicle service pits not accessible to the public.
    7. In assembly seating areas at cross aisles in accordance with Section 1030.17.2.
    8. On the loading side of station platforms on fixed guideway transit or passenger rail systems.

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    1. Portions of an occupiable roof located less than 30 inches (762 mm) measured vertically to adjacent unoccupiable roof areas where approved guards are present at the perimeter of the roof.
    2. At portions of an occupiable roof where an approved barrier is provided. 11. Elevated facility observation station access hatches at detention facilities.

    1015.2.1 Glazing. Where glass is used to provide a guard or as a portion of the guard system, the guard shall comply with Section 2407. Where the glazing provided does not meet the strength and attachment requirements of Section 1607.9, complying guards shall be located along glazed sides of open-sided walking surfaces.

  • CRC § 12.7 High relevance — show source text

    Exceptions:

    1. A decrease in the clearance due to the curvature or angle of handrail returns shall be allowed.
    2. Mounting flanges not more than [1] / 2 -inch (12.7 mm) in thickness at the returned ends of handrails shall be allowed.

    [BE] 1014.9 Projections. On ramps and on ramped aisles that are part of an accessible route, the clear width between handrails shall be 36 inches (914 mm) minimum. Projections into the required width of aisles, stairways and ramps at each side shall not exceed 4 [1] / 2 inches (114 mm) at or below the handrail height. Projections into the required width shall not be limited above the minimum headroom height required in Section 1011.3. Projections due to intermediate handrails shall not constitute a reduction in the egress width. Where a pair of intermediate handrails are provided within the stairway width without a walking surface between the pair of intermediate handrails and the distance between the pair of intermediate handrails is greater than 6 inches (152 mm), the available egress width shall be reduced by the distance between the closest edges of each such intermediate pair of handrails that is greater than 6 inches (152 mm).

    In Group I-2 occupancies, ramps required for exit access shall not be less than 8 feet in width and handrails are permitted to protrude 3 [1] / 2 inches from the wall on both sides. For ramps used as exits and stairways used for the movement of bed and litter patients, the clear width between handrails shall be 44 inches (1118 mm) minimum.

    [BE] 1014.10 Intermediate handrails. Stairways shall have intermediate handrails located in such a manner that all portions of the stairway minimum width or required capacity are within 30 inches (762 mm) of a handrail. On monumental stairs, handrails shall be located along the most direct path of egress travel.

    SECTION 1015—GUARDS

    [BE] 1015.1 General. Guards shall comply with the provisions of Sections 1015.2 through 1015.7. Operable windows with sills located more than 72 inches (1829 mm) above finished grade or other surface below shall comply with Section 1015.8.

    [BE] 1015.2 Where required. Guards shall be located along open-sided walking surfaces, such as mezzanines, equipment platforms, aisles, stairs, ramps and landings, that are located more than 30 inches (762 mm) measured vertically to the floor or grade below at any point within 36 inches (914 mm) horizontally to the edge of the open side and at the perimeter of occupiable roofs. Guards shall be adequate in strength and attachment in accordance with Section 1607.9 of the California Building Code .

    Exception: Guards are not required for the following locations:

    1. On the loading side of loading docks or piers.
    2. On the audience side of stages and raised platforms, including stairs leading up to the stage and raised platforms.
    3. On raised stage and platform floor areas, such as runways, ramps and side stages used for entertainment or presentations.
    4. At vertical openings in the performance area of stages and platforms.
    5. At elevated walking surfaces appurtenant to stages and platforms for access to and utilization of special lighting or equipment.
    6. Along vehicle service pits not accessible to the public.

    10-38 2025 CALIFORNIA FIRE CODE

  • CRC § 359.1 Medium relevance — show source text

    Exception: Guards are not required where personal fall arrest anchorage connector devices that comply with ANSI/ASSE Z 359.1 are installed.

    10-38 2025 CALIFORNIA BUILDING CODE

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    MEANS OF EGRESS

    1015.8 Window openings. Windows in Group R-1, R-2 and R-3 buildings including dwelling units, where the bottom of the clear opening of an operable window is located less than 36 inches (914 mm) above the finished floor and more than 72 inches (1829 mm) above the finished grade or other surface below on the exterior of the building, shall comply with one of the following:

    1. Where the bottom of the clear opening of the window is located more than 72 inches (1829 mm) and less than 75 feet (22 860 mm) above the finished grade or other surface below on the exterior of the building, the window shall comply with one of the following: 1.1. Operable windows where the openings will not allow a 4-inch-diameter (102 mm) sphere to pass through the opening when the window is in its largest opened position, provided that the opening is not required for emer gency escape or rescue. 1.2. Operable windows where the openings are provided with window fall prevention devices that comply with ASTM F2090.

    1.3. Operable windows where the openings are provided with window opening control devices that comply with ASTM F2090. The window opening control device, after operation to release the control device allowing the window to fully open, shall not reduce the minimum net clear opening area of the window unit to less than the area required by Section 1031.3.1 for emergency escape and rescue openings. 2. Where the bottom of the clear opening of the window is located 75 feet (22,860 mm) or more above the finished grade or other surface below on the exterior of the building, the window shall comply with one of the following: 2.1. Operable windows where the openings are provided with window fall prevention devices that comply with ASTM F2090.

    2.2. Operable windows where the openings will not allow a 4-inch-diameter (102 mm) sphere to pass through the opening when the window is in its largest opened position. 2.3. Window fall prevention devices that comply with ASTM F2006.

    SECTION 1016—EXIT ACCESS

    1016.1 General. The exit access shall comply with the applicable provisions of Sections 1003 through 1015. Exit access arrangement shall comply with Sections 1016 through 1021.

    1016.2 Egress through intervening spaces. Egress through intervening spaces shall comply with this section.

    1. Exit access through an enclosed elevator lobby is permitted in other than a Group I-2 . Where access to two or more exits or exit access doorways is required in Section 1006.2.1, access to not less than one of the required exits shall be provided without travel through the enclosed elevator lobbies required by Section 3006. Where the path of exit access travel passes through an enclosed elevator lobby, the level of protection required for the enclosed elevator lobby is not required to be extended to the exit unless direct access to an exit is required by other sections of this code.

Frequently asked questions

Can insect screening be used as a guard?

No. Insect screening is not a guard and does not satisfy the guard requirement where § R321.1.1 triggers a guard.

If a guard top is used as the handrail, what height must it be on a stair?

When the guard top serves as the handrail on the open side of stairs, the top must be 34 in. to 38 in. above the line connecting the nosings. § R321.1.2 (exception).

My bedroom window is used for egress — can I add a window restrictor for child safety?

Yes — but if the window is a required emergency escape opening, any window opening control device must allow the window, once released, to provide the net clear opening required by § R319.2.1/2 (5.7 sq ft; 24 in. × 20 in.). § R321.2.2.

Are larger handrail profiles allowed if they have a finger recess?

Yes — Type II handrail profiles (perimeter > 6-1/4 in.) are allowed if they include the required finger recess dimensions specified in § R320.6 (2).

Do I have to follow the alternating‑tread device dimensions if I install one?

Yes — alternating tread devices are limited in where they can be used and must meet the specific tread/riser/width rules in § R318.7.12 and § R318.7.12.1. They are not a general replacement for conventional stairs.

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