R314 Mezzanines — 2025 California Residential Code

Mezzanines shall comply with Sections R314.2 through R314.5.

Exception: Sleeping lofts in dwelling units and sleeping units shall be permitted to comply with Section R315, subject to the limitations in Section R315.2.

The clear height above and below mezzanine floor construction shall be not less than 7 feet (2134 mm).

The aggregate area of a mezzanine or mezzanines shall be not greater than one-third of the floor area of the room or space in which they are located. The enclosed portion of a room shall not be included in a determination of the floor area of the room in which the mezzanine is located.

Exception: The aggregate area of a mezzanine located within a dwelling unit equipped with an automatic sprinkler system in accordance with Section R309 shall not be greater than one-half of the floor area of the room, provided that the mezzanine meets all of the following requirements:

1. Except for enclosed closets and bathrooms, the mezzanine is open to the room in which such mezzanine is located.
2. The opening to the room is unobstructed except for walls not more than 42 inches (1067 mm) in height, columns, beams and posts.
3. The exceptions to Section R314.5 are not applied.

The means of egress for mezzanines shall comply with the applicable provisions of Section R318.

Mezzanines shall be open and unobstructed to the room in which they are located except for walls not more than 42 inches (1067 mm) in height, columns, beams and posts.

Exception: Mezzanines, or portions of the mezzanines, are not required to be open to the room in which they are located, provided that the enclosed spaces on the mezzanine are not greater than 10 percent of the mezzanine area.