District of Columbia, DC Accessory Structures: Carport Rules (2026)

Carports in DC fall under the accessory structure provisions of the DC Zoning Regulations (DCMR Title 11 Subtitle D section 304 for R zones). A DOB building permit is required for any carport, regardless of whether it is attached or freestanding, prefabricated or custom-built. Zoning standards for R-zone carports include: 5-foot minimum side and rear setback, maximum height of 20 feet (or 15 feet in some R-3 areas), and inclusion in the lot occupancy percentage (typically 40-60 percent depending on zone). Structural requirements under the 2017 DC Construction Codes include 90 mph wind uplift design, 30-pound-per-square-foot snow load, and fire separation from property lines (5/8-inch Type X drywall required on underside if closer than 3 feet). Most of DC's rowhouse neighborhoods have little rear yard space, making carports impractical; they are most common in Ward 3 single-family detached areas and on some larger Ward 7/8 lots. Historic districts treat carports strictly as non-traditional and usually deny new visible construction. Off-street parking in the front setback is generally prohibited under DCMR 11-C 704.