Accessory Structures in Rockville, MD (2026)
5 verified accessory structures rules for Rockville, Maryland, sourced directly from the municipal code and official government pages.
Verified from official government sources
ADU Rules
Rockville permits attached accessory dwelling units as a conditional use in residential zones under zoning text amendment TXT2023-00263, effective April 9, 2024. Attached ADUs may be built within or as an addition to single-unit detached homes. The property owner must occupy either the main dwelling or the ADU for at least six months per year, and the ADU cannot exceed 50 percent of the primary dwelling floor area.
Rockville Accessory Dwelling Unit Regulations
Some RestrictionsShed Rules
Rockville requires a building permit for sheds and accessory buildings. Chapter 25 of the Rockville City Code sets a maximum footprint of 750 square feet for any single accessory building and 1,000 square feet total for all accessory buildings on one lot. Minimum setback is 3 feet from lot lines, with additional setbacks required for structures taller than 12 feet.
Rockville Shed and Accessory Building Rules
Some RestrictionsGarage Conversions
Garage conversions in Rockville require a building permit and must comply with zoning, building, and fire code requirements. Converting a garage to living space may be treated as an attached ADU under the 2024 zoning text amendment, requiring conditional use approval. The conversion must maintain required off-street parking spaces for the property.
Rockville Garage Conversion Regulations
Some RestrictionsCarport Rules
Carports in Rockville are regulated as accessory structures under Chapter 25 of the City Code and require a building permit. They must meet rear yard setback requirements of at least 3 feet from lot lines and cannot exceed the maximum height or coverage limits for accessory buildings. Carports in front yards are generally not permitted in residential zones.
Rockville Carport Regulations
Some RestrictionsTiny Homes
Rockville does not have a specific tiny home ordinance. Tiny homes on foundations may qualify as attached ADUs under the 2024 zoning amendment if they meet conditional use and size requirements. Tiny homes on wheels are classified as recreational vehicles and cannot serve as permanent dwellings. All habitable structures must meet the International Residential Code minimum standards adopted by the city.
Rockville Tiny Home Regulations
Heavy RestrictionsLooking for Montgomery County county-wide rules?
County ordinances apply to unincorporated areas and may supplement Rockville city rules.
Accessory Structures in Montgomery County →