Sumter County, FL Accessory Structures: ADU Rules (2026)

Section 13-511 of the Land Development Code lets one accessory dwelling unit (ADU) sit alongside one principal dwelling on the same lot in every agricultural and residential zoning category, and the ADU does not count as a separate unit for density purposes. The property must be at least one-half acre; owners may aggregate smaller lots to reach that size, but before a building permit issues they must record a document in the county's public records that bars future subdivision of the combined lots. The ADU's living area must be at least 400 square feet and cannot exceed 40 percent of the principal structure's gross floor area, and both the principal home and the ADU must be site-built, not manufactured units brought in as a unit.

Outside an urban development area, neither structure may be a townhouse. The ADU has to match the principal home's appearance, share its driveway, and comply with every setback in the code, and construction cannot create parking or drainage problems. An ADU can never be sold, transferred or conveyed separately from the principal dwelling. Short of building a full ADU, the code separately allows renting one room and bath in a single-family home to no more than two people in any residential district, unless a deed restriction says otherwise.