Under certain circumstances, the Arlington County Zoning Ordinance (ACZO) allows homeowners to create a secondary dwelling unit on their property. A secondary dwelling unit typically takes the form of an apartment with its own bath, kitchen, and living facilities located on the same lot as a larger, main dwelling unit.
The ACZO only allows a secondary dwelling unit if the lot is improved with a one-family detached dwelling and located in a Residential (R) zoning district (i.e. R-20, R-10, R-8, R-6, R-5, R-10T, R-15- 30T, and R-2-7). If you do not know your dwelling unit type or zoning district, use the Real Estate Assessments database to query your address.
The two types of secondary dwelling units permitted by the ACZO are as follows: