Expansion and Modification of Nonconforming Buildings in Arlington County
Arlington County allows the maintenance and repair of nonconforming buildings, but any physical additions or enlargements must generally comply with all current zoning regulations for the district in which the property is located. While owners of one-family and two-family dwellings in most Residential (R) and Multiple-family (RA) districts are granted significant flexibility to expand their structures, commercial and larger residential buildings that do not comply with bulk or placement standards are strictly limited to cumulative additions that do not exceed 50 percent of the original floor area as of July 15, 1950.
General Rules for Modification and Repair
In Arlington County, nonconforming buildings and structures may be maintained in their current state [§16.2.2]. Repairs and alterations are permitted, though structural alterations are generally prohibited unless they are required by law or specifically authorized by the Zoning Ordinance [§16.2.3.A].
Residential Interior Repairs
Regardless of other restrictions, Arlington County permits interior repairs and alterations (both structural and non-structural) for the following nonconforming residential structures, provided the work is entirely contained within the existing exterior walls:
- One-family and two-family dwellings and accessory structures in R and RA districts.
- Existing nonconforming townhouses and multifamily dwellings in R2-7 and RA districts.
- Expanded housing option (EHO) developments (for the purpose of maintaining or adding units) [§16.2.3.B].
Standards for Additions and Enlargements
The Arlington County Zoning Ordinance establishes strict parameters for the physical expansion of nonconforming structures. The primary requirement is that any new addition must conform to the current regulations of the district regarding height, setbacks, and coverage [§16.2.4.A].
The 50 Percent Floor Area Limitation
If a building is nonconforming specifically due to height, placement, or lot coverage, it may only be expanded if the addition conforms to current district rules. Furthermore, the total aggregate floor area of all separate additions and expansions made since July 15, 1950, cannot exceed 50 percent of the floor area that existed on that date [§16.2.4.B].
Parking Requirements for Expansion
If a nonconforming building lacks sufficient automobile parking spaces as required by Arlington County standards, the building cannot be altered or expanded unless additional parking is provided to meet the requirements for the entire building, not just the new addition [§16.2.4.C].
District-Specific Exceptions
Arlington County provides various exceptions to the standard nonconforming rules based on the specific zoning district and the type of residential use.
| Use Type | Allowed Expansion/Modification | Applicable Districts |
|---|---|---|
| One-family Dwellings | General prohibitions on adding to or moving nonconforming structures do not apply. | R-5, R-6, R-8, R-10, R-20, and R2-7 |
| Two-family Dwellings | General prohibitions on adding to nonconforming structures do not apply. | R-5, R-6, R2-7, RA14-26, RA8-18, RA7-16, and RA6-15 |
| Townhouses & Multifamily | Permitted only for adding or expanding window wells, areaways, decks, ramps, and steps. | R2-7, RA14-26, RA8-18, RA7-16, and RA6-15 |
| Expanded Housing Option (EHO) | May construct additions over existing walls encroaching on setbacks, provided the new wall does not encroach further than the wall below. | R-5, R-6, R-8, R-10, R-20 |
Vertical Encroachments for Dwellings
For nonconforming one-family, two-family, and EHO developments, Arlington County allows the construction of an addition over an existing part of the house that already encroaches on a required setback or yard. This is permitted as long as the new upper-story wall does not encroach any further than the existing wall below it. However, this vertical expansion is not permitted over encroaching garages or porches [§16.2.4.E.5].
Restoration of Damaged Buildings
If a nonconforming residential or commercial building in Arlington County is damaged or destroyed by a calamity—such as fire, flood, wind, or earthquake—it may be repaired, rebuilt, or replaced. The goal of this restoration must be to eliminate nonconforming features or reduce the nonconformity to the greatest extent possible without needing a variance [§16.2.5.A].
For one-family and two-family dwellings, the structure may be rebuilt within its original footprint, height, and number of stories as they existed prior to the damage [§16.2.5.D]. Generally, repairs or replacement must be completed within two years of the disaster [§16.2.5.C].
Sections Cited
- §16.2 Nonconforming Buildings and Structures
- §16.2.2 Maintenance permitted
- §16.2.3 Repairs, alterations
- §16.2.4 Additions, enlargements, moving
- §16.2.5 Restoration of damaged building
- §18.2 General Terms Defined