R315 Sleeping Lofts — 2025 California Residential Code

Where provided in dwelling units or sleeping units, sleeping lofts shall comply with this code as modified by Sections R315.2 through R315.5. Sleeping lofts constructed in compliance with this section shall be considered a portion of the story below. Such sleeping lofts shall not contribute to the number of stories as regulated by this code.

Exceptions: Sleeping lofts need not comply with Section R315 where they meet any of the following conditions:

1. The sleeping loft has a depth of less than 3 feet (914 mm).
2. The sleeping loft has a floor area of less than 35 square feet (3.3 m [2] ).
3. The sleeping loft is not provided with a permanent means of egress.

Sleeping lofts shall comply with the following conditions:

1. The sleeping loft floor area shall be less than 70 square feet (6.5 m [2] ).
2. The sleeping loft ceiling height shall not exceed 7 feet (2134 mm) for more than one-half of the sleeping loft floor area.

The clear height below the sleeping loft floor construction shall not be less than 7 feet (2134 mm). The ceiling height above the finished floor of the sleeping loft shall not be less than 3 feet (914 mm). Spaces adjacent to the sleeping loft with a sloped ceiling measuring less than 3 feet (914 mm) from the finished floor to the finished ceiling shall not contribute to the sleeping loft floor area.

The aggregate area of all sleeping lofts and mezzanines within a room shall comply with Section R314.3.

Exception: The area of a single sleeping loft located within a dwelling unit or sleeping unit equipped with an automatic sprinkler system in accordance with Section R309 shall not be greater than two-thirds of the area of the room in which it is located, provided that no other sleeping lofts or mezzanines are open to the room in which the sleeping loft is located.

A permanent means of egress shall be provided for sleeping lofts. The means of egress shall comply with Section R318 as modified by Sections R315.5.1 through R315.5.3.

R315.5.1 Ceiling height at sleeping loft means of egress. A ceiling height of not less than 3 feet (914 mm) shall be provided for the entire width of the means of egress from the sleeping loft.

R315.5.2 Stairways. Stairways providing egress from sleeping lofts shall be permitted to comply with Sections R315.5.2.1 through R315.5.2.3.

3-60 2025 CALIFORNIA RESIDENTIAL CODE

BUILDING PLANNING

R315.5.2.1 Width. Stairways providing egress from a sleeping loft shall not be less than 17 inches (432 mm) in clear width at or above the handrail. The width below the handrail shall be not less than 20 inches (508 mm).

R315.5.2.2 Treads and risers. Risers for stairs providing egress from a sleeping loft shall be not less than 7 inches (178 mm) and not more than 12 inches (305 mm) in height. Tread depth and riser height shall be calculated in accordance with one of the following formulas:

1. The tread depth shall be 20 inches (508 mm) minus four-thirds of the riser height.
2. The riser height shall be 15 inches (381 mm) minus three-fourths of the tread depth.

R315.5.2.3 Landings. Landings at stairways providing egress from sleeping lofts shall comply with Section R318.7.6, except that the depth of landings in the direction of travel shall be not less than 24 inches (610 mm).

R315.5.3 Ladders. Ladders used as a means of egress from sleeping lofts shall comply with Sections R315.5.3.1 and R315.5.3.2.

R315.5.3.1 Size and capacity. Ladders providing egress from sleeping lofts shall have a rung width of not less than 12 inches (305 mm), and 10-inch (254 mm) to 14-inch (356 mm) spacing between rungs. Ladders shall be capable of supporting a 300pound (136 kg) load on any rung. Rung spacing shall be uniform within 3/8 inch (9.5 mm).

R315.5.3.2 Incline. Ladders shall be inclined at 70 to 80 degrees from horizontal.