Accessory Dwelling Units, or ADUs, continue to gain attention as buyers and homeowners look for more flexible housing options. ADUs can include in-law suites, garage apartments, backyard cottages, or other secondary living spaces on the same property as a primary residence.
Across the Greater Piedmont region, the rules vary significantly by jurisdiction. Fauquier County provides a relatively straightforward administrative process, while Rappahannock County, the Town of Culpeper, and the Town of Warrenton require additional approvals. Culpeper County has more property-specific rules tied to factors such as zoning, acreage, and the type of secondary dwelling proposed.
Madison County recently made an important change. On October 7, 2026, the County adopted an ordinance allowing one ADU by right in R-1, R-2, and R-3 districts, provided ordinance requirements are met. The new rules do not require additional parking or owner occupancy, but ADUs cannot be sold separately and cannot be rented for fewer than 30 consecutive days. A-1 Agricultural and C-1 Conservation properties are not currently included, although the County may continue discussing expansion into those districts.
For REALTORS®, the key message is simple: never assume an ADU is permitted based only on the general ordinance or zoning district. Before marketing a property as having ADU potential, agents should contact the applicable planning and zoning office directly and verify what is allowed on that specific parcel.
That parcel-level check matters because setbacks, septic capacity, existing structures, subdivision history, permits, building-code requirements, HOA restrictions, and other factors may affect whether an ADU can actually be built or legally occupied.
GPR will continue monitoring local ADU policies because these rules can affect property value, housing choice, multigenerational living, and opportunities for homeowners. Staying informed helps REALTORS® give clients better guidance while avoiding promises that zoning may not support.
Download File (10-09-2026-gpr-adu-rules.pdf)