St. Petersburg, FL Accessory Structures: ADU Permits (2026)

St. Petersburg's Land Development Regulations (LDR), codified as City Code Chapter 16, govern accessory dwelling units. ADUs are typically permitted as accessory uses in NS-1, NSM-1, NSM-2, NT-1, NT-2, and most NTM districts subject to LDR standards in Chapter 16.40 (Accessory Uses and Structures) and Chapter 16.50 (Specific Use Standards). Common requirements: ADU floor area capped (commonly 750-800 sq ft or a percentage of the principal dwelling, whichever is less); compliance with underlying district setbacks; one additional off-street parking space; one entrance not facing the primary street; lot must meet minimum area; principal dwelling must remain conforming. The Florida ADU statute at Fla. Stat. §163.31771 (enacted via HB 1031, 2024) directs local governments to consider permissive ADU policies but does not preempt local size, setback, or owner-occupancy rules. Permits are filed with the City of St. Petersburg Construction Services and Permitting Department, Municipal Services Center, 1 4th Street North. Required submittals: zoning verification, signed and sealed plans for ADUs over the residential-prescriptive threshold, plus separate building, electrical, plumbing, and mechanical permits under the Florida Building Code 8th Edition (2023, effective Dec 31, 2023). St. Petersburg sits entirely on a peninsula and many parcels lie in FEMA Special Flood Hazard Areas, including AE and VE (coastal velocity) zones along Tampa Bay, Boca Ciega Bay, and the Gulf — elevation certificates and floodplain-development review under City Code Chapter 8 are required for affected lots. Hurricane wind-load design uses 150 mph ultimate wind speed per FBC for Pinellas coastal exposure.