ADU rules in Bixby

A detached ADU is allowed only by Board of Adjustment special exception after a public hearing. Bixby's zoning code allows no more than one single-family dwelling per lot except for a PUD or an ADU 'approved by special exception' under §11-8-5 (Ord. 2031, 2009). A detached ADU must meet the rules for a detached accessory building, which in residential districts means the rear yard only and at least 5 feet from interior lot lines. Lots under a recorded covenant allowing only one dwelling unit per lot are not eligible.

An attached or internal ADU goes through the same special exception route. The definition in §11-2-1 covers a unit 'incorporated within, attached to, or detached from' a single-family home that has its own sleeping, cooking and sanitation facilities. Every ADU is limited to one bedroom and three occupants and must match the main house's exterior materials. The covenant bar also applies to attached ADUs.

Section 11-8-5 sets no square-footage limit for an ADU itself; it limits the unit to one bedroom, and §11-2-1 caps occupancy at three persons. Because a detached ADU 'shall meet the requirements prescribed for a detached accessory building', it falls under §11-8-8.B.5. In the RE and RS districts, all accessory buildings combined may cover no more than 20% of the rear yard or 800 sq ft of floor area, whichever is less. Lots of one acre or more get 11.6% more, plus another 11.6% for each quarter acre over 1.25 acres. The total can never exceed 2,400 sq ft or the main house's first floor, and no accessory building may be taller than the primary dwelling. The Board of Adjustment can also impose size conditions case by case.

Neither §11-8-5 nor the ADU definition in §11-2-1 requires the owner to live on the property, and a full-text search of the code for 'owner occupied' finds only a fire-code amendment. However, the Board of Adjustment 'shall place reasonable conditions on the special exception approval', so an individual approval could carry an occupancy condition. Oklahoma has no state owner-occupancy rule either way.

Section 11-8-5 has no parking standard for ADUs. Use Unit 6 requires '2 per dwelling unit' for a single-family detached dwelling. The code does not say whether that ratio also applies to the subordinate ADU, which is not listed as a use in any use unit. In practice, extra parking is decided through the special-exception conditions the Board 'shall place' to prevent 'undue adverse impacts'. Applicants should expect the Board to look at parking.

Every ADU needs a Board of Adjustment special exception. Under §11-4-9 that means a filed application, a public hearing, and approval by a concurring vote of three members after a finding that the ADU 'will be in harmony with the spirit and intent of this title, and will not be injurious to the neighborhood'. The Board must attach conditions. The FY27 fee schedule (updated July 1, 2026) lists a $350 special exception fee and a $150 permit for a new detached accessory building. An approval that is not used within three years is void.

The code does not prohibit renting an ADU, but §11-8-5.D bars subdividing or 'otherwise segregat[ing] in ownership' an ADU from the main home, and §11-2-1 limits it to three occupants. Bixby has no short-term rental license, registration or zoning definition: searches of the code for 'short term', 'short-term rental', 'vacation', 'bed and breakfast' and 'airbnb' found no such rules. The city's 5% hotel tax (Title 2, Ch. 5, Art. G) defines a hotel as a facility with five or more rooms, so a single ADU does not appear to be covered by it. The Board can still restrict rentals through special-exception conditions.