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

11B-233.3.1.2.6.1 Single building with one common (lobby) entrance.

The following may only be used for determining required access to multifamily dwelling units, in a single building with one common (lobby) entrance, located on a site with difficult terrain conditions or unusual characteristics:

All ground floor units in non-elevator buildings shall be adaptable and on an accessible route unless an accessible route to the common (lobby) entrance is not required as determined by Test No. 1, Individual Building Test, or Test No. 3, Unusual Characteristics Test, as described in this section.

Sites where either Test No. 1 or Test No. 3 is used and it is determined that an accessible route to the common (lobby) entrance is not required, a minimum of 20 percent of the ground floor dwelling units shall comply with Section 11B-809.6, and all remaining ground floor dwelling units shall comply with the features listed in Section 11B-233.3.1.2.6.2 unless exempted by Test No. 3, Unusual Characteristics Test.

Test No. 1 -- Individual Building Test may only be used if the site has terrain over 15 percent slope.

Test No. 3 -- Unusual Characteristics Test may be used if applicable.

Provisions to Test Nos. 1 and 2. Where a building elevator is provided only as means of creating an accessible route to dwelling units on a ground floor, the building is not considered to be an elevator building for purposes of this code; hence, only the ground floor dwelling units would be covered.