Loudoun County, VA Building Setbacks & Zoning: Structure Height Limits (2026)

Loudoun County Revised 1993 Zoning Ordinance sets maximum heights by district. R-1 and R-2: 35 feet or 2.5 stories, whichever is less, measured from average finished grade to roof peak per Zoning Ord. §6-1300. TR (Transitional Residential): 35 ft. R-4 and R-8 (higher density): 40-45 ft. PD-H: governed by approved Concept Development Plan — typically 35-40 ft, but some mixed-use projects like One Loudoun allow 60-75 ft for mid-rise. A-3 (Agricultural Rural): 40 ft for dwellings, exemption for silos and agricultural structures (75 ft+). CLI and IP (Industrial): 60 ft standard, extendable via SPEX. PD-IP (Planned Industrial, Ashburn's Data Center Alley): heights up to 90-100 ft for data centers via special use permit amendments post-2020. Commercial Community (CC) and Town Center (TC): 50-75 ft. Chimneys, bell towers, antennas, mechanical penthouses exempt up to 15 ft above limit. CRITICAL: Federal Aviation Administration Part 77 imaginary surfaces around Washington Dulles International (IAD) impose maximum heights that may be STRICTER than zoning — any construction over 200 ft or in the primary/approach surfaces requires FAA 7460-1 filing. This often caps development near IAD regardless of zoning.