Collinsville

Tulsa County, OK (669,000 residents including Tulsa) administers a county zoning ordinance for unincorporated territory through the Tulsa Metropolitan Area Planning Commission (TMAPC), a joint city-county planning agency. Major cities include Tulsa, Broken Arrow, Owasso, Sand Springs, Bixby, Jenks, Sapulpa-portion, Glenpool, Collinsville, Skiatook.

• Tulsa County Zoning Code
• City of Tulsa Zoning Code (Title 42)

State-floor overlay: Oklahoma has not enacted statewide ADU preemption.

Tulsa County administers flood-hazard, and (where mapped) coastal, wildland-fire, historic, and airport overlays that shape ADU project feasibility. The most consistent overlay across the county is FEMA NFIP floodplain regulation; other overlays apply to specific geographies inside the county.

• FEMA NFIP Special Flood Hazard Areas in Tulsa County — A new ADU in a mapped SFHA must be elevated to or above the Base Flood Elevation; cost impact on the project is often material.
• Historic districts and individually-listed historic resources

Tulsa County issues building permits for parcels in unincorporated territory through its development services / planning department, with separate review tracks for zoning conformance, building-code compliance, on-site sewage where applicable, floodplain compliance, and addressing. Inside incorporated municipalities, city departments handle their own permits; the county's authority is geographically limited to unincorporated territory. An ADU permit application is typically processed as a residential building permit with a zoning verification step against the county's ordinance for the parcel's zoning district.