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Accessory Structures in Gaithersburg, MD (2026)

5 verified accessory structures rules for Gaithersburg, Maryland, sourced directly from the municipal code and official government pages.

Verified from official government sources

ADU Rules

Gaithersburg permits accessory dwelling units in most residential zones following its ADU-friendly zoning amendments. ADUs may be attached to or detached from the primary dwelling. Units are limited to 50 percent of the primary dwelling floor area or 1,200 square feet, whichever is less. One off-street parking space is required. Owner occupancy of either the primary or accessory unit is required.

Gaithersburg Accessory Dwelling Unit (ADU) Rules

Few Restrictions

Shed Rules

Storage sheds in Gaithersburg are regulated by the city's zoning ordinance and building code. Sheds under 200 square feet do not require a building permit but must comply with setback and height requirements. Sheds 200 square feet or larger require a building permit. All sheds must be in rear yards and set back at least 3 feet from property lines in most residential zones.

Gaithersburg Storage Shed Regulations

Some Restrictions

Garage Conversions

Converting a garage to living space in Gaithersburg requires a building permit and zoning review. The conversion must meet residential building code standards for habitable space including egress, insulation, ventilation, and ceiling height. Off-street parking requirements must still be satisfied after the conversion. Garage-to-ADU conversions follow the city's accessory dwelling unit regulations.

Gaithersburg Garage Conversion Regulations

Some Restrictions

Carport Rules

Carports in Gaithersburg are treated as accessory structures and require a building permit. They must meet setback requirements for the applicable zoning district. Carports may be attached or detached from the primary dwelling. Front-yard carports are generally not permitted in single-family residential zones unless approved through the site plan process.

Gaithersburg Carport Regulations

Some Restrictions

Tiny Homes

Tiny homes in Gaithersburg must comply with the International Residential Code minimum standards for dwelling units. Tiny homes on foundations may qualify as accessory dwelling units subject to ADU regulations. Tiny homes on wheels are classified as recreational vehicles and cannot be used as permanent residences. Minimum dwelling unit size is generally 150 square feet under the IRC Appendix Q provisions.

Gaithersburg Tiny Home Regulations

Some Restrictions

Looking for Montgomery County county-wide rules?

County ordinances apply to unincorporated areas and may supplement Gaithersburg city rules.

Accessory Structures in Montgomery County