2019 California Standards for Accessible Design Guide (effective January 1, 2020 with July 1, 2021 amendments)

1010.1.7 Thresholds.

Thresholds at doorways shall not exceed ¾ inch (19.1 mm) in height above the finished floor or landing for sliding doors serving dwelling units or ½ inch (12.7 mm) above the finished floor or landing for other doors. Raised thresholds and floor level changes greater than ¼ inch (6.4 mm) at doorways shall be beveled with a slope not greater than one unit vertical in two units horizontal (50-percent slope).

Exceptions:

1. In occupancy Group R-2 or R-3, threshold heights for sliding and side-hinged exterior doors shall be permitted to be up to 7¾ inches (197 mm) in height if all of the following apply:

     1.1. The door is not part of the required means of egress.

     1.2. The door is not part of an accessible route as required by Chapter 11A or 11B.

     1.3. The door is not part of an adaptable or accessible dwelling unit.

2. In adaptable or accessible dwelling units, where Exception 5 to Section 1010.1.5 permits a 4-inch (102 mm) elevation change at the door, the threshold height on the exterior side of the door shall not exceed 4¾ inches (120 mm) in height above the exterior deck, patio or balcony for sliding doors or 4½ inches (114 mm) above the exterior deck, patio or balcony for other doors.