ADU rules in Sandy

Detached accessory apartments are prohibited; the unit shall not occupy any accessory building and must share a common wall with the primary dwelling. A separate detached 'guesthouse' (max 400 sq ft, lot of 20,000 sq ft or more) can get an administrative special use permit, but it may not be rented and may not have a full kitchen, so it is not a rentable ADU.

One accessory apartment allowed within a single-family dwelling (e.g. basement or connected by a common wall; connection through a breezeway or garage not allowed), via administrative special use permit plus an accessory apartment business license.

§21-11-1 sets no floor-area cap for accessory apartments or extended living areas (read in full); the only size cap in the section is 400 sq ft for detached guesthouses, which are a separate non-rentable use.

Fee title owner (individual or family trustor with 50%+ ownership; not an LLC/corporation) must live in the primary dwelling as their primary residence, proven by tax returns, government ID, and a notarized affidavit.

Off-street parking must be available for the unit's occupants per the city's adopted residential parking standards; §21-11-1 states no specific space count. Any additional occupant vehicles must be accommodated on-site; on-street parking is reserved for visitors.

Administrative special use permit from the Community Development Department plus an accessory apartment business license (staff-level approval, not a hearing). The permit expires on sale of the property, change of the owner's residence, or business license expiration, and is not transferable.

Renting the unit for under 30 consecutive days is prohibited unless separate short-term rental approvals are obtained, and no portion of the property may be rented short-term and long-term at the same time. Occupants must be a single additional family; subleasing is prohibited.