BACKYARD OFFICE REQUIREMENTS:
Permit Restrictions
The decision on whether or not a Design Review is needed from the planning department depends on the zoning, square footage, floor area ratio of the existing house, and proposed lot coverage but will most likely be a staff-level decision
Building permits are dependent on the type of structure and whether or not the space is conditioned
The addition of electricity, a deck, or slab foundation (if needed) would all most likely trigger a building permit
Height and Setback Restrictions

ADU REQUIREMENTS:
Zoning Restrictions
The following districts can build ADUs:
Single family residential: R-8, R-8.5, R-10, R-12, R-15, R-20, R-40
Duplex & multifamily: D-3, M-0.75, M-1, M-2, M-2.5, M-3
Other: M-H-D, H-P-D, M-U, O-S-R, HO P-D, P-D, SFH-PD1, MU-C, MU-R, MU-D
Setback and Height Restrictions
Maximum height: 16 feet
Setback Requirements:
Rear lot: 4 feet
Side lot: 4 feet
Any existing structure: 6 feet
Other Restrictions
Owners may be required to sign something preventing them from doing
The design of the ADU must be consistent with the architecture of the main house (including building form, exterior siding and/or trim, roof form and materials, and windows)
Possible extra restrictions if:
the lot has an average slope of >15%
the lot is within 50 feet of a fault line or creek bed