RA8-18 Multiple-family Dwelling District: Arlington County Zoning Guide
The RA8-18 Multiple-family Dwelling district in Arlington County allows for mid-density residential development, including multiple-family units at a standard density of approximately 36 units per acre and heights reaching up to 75 feet under specific site plan approvals. Permitted uses in the RA8-18 district range from one-family detached homes and townhouses to institutional facilities like hospitals and schools, provided they meet strict dimensional and parking requirements.
Purpose of the RA8-18 District
In Arlington County, the RA8-18 district is categorized under the Multiple-family (RA) district grouping [§1.7.1]. While specific purpose statements for RA8-18 are reserved within the ordinance, the district is designed to facilitate the development of multiple-family dwellings, townhouses, and semidetached units within a framework that balances residential density with neighborhood character [§6.3.1].
Permitted Land Uses
Arlington County designates specific uses as permitted by-right (P), requiring a use permit (U), or requiring site plan approval (S) within the RA8-18 district.
Residential Uses
- One-family detached: Permitted by-right [§6.1.2].
- Duplexes and Semidetached: Permitted by-right or via site plan [§6.1.2].
- Multiple-family: Permitted by-right or via site plan [§6.1.2].
- Townhouses: Permitted by-right or via site plan [§6.1.2].
- Independent living facilities: Allowed via site plan approval [§6.1.2].
- Recovery residences: Permitted by-right for eight or fewer residents; larger facilities require a use permit [§12.3.9].
Public and Institutional Uses
- Churches, mosques, and temples: Permitted by-right [§6.1.2].
- Schools (elementary, middle, and high): Requires use permit approval [§6.1.2].
- Hospitals: Requires use permit approval [§6.1.2].
- Colleges and universities: Requires use permit approval [§6.1.2].
Commercial and Other Uses
- Bed and breakfasts: Allowed with a use permit [§6.1.2].
- Offices (medical or dental): Allowed via use permit in existing institutional structures or new buildings depending on district-specific conditions [§12.3.7].
- Agriculture: All agricultural uses are permitted by-right [§6.1.2].
Density and Dimensional Standards
Arlington County enforces strict standards for the RA8-18 district regarding lot size, building height, and unit density. These vary based on whether the project is developed by-right or through a special exception site plan.
By-Right Development Standards
The following table outlines the minimum requirements for by-right construction in the RA8-18 district [§6.3.4].
| Type of Standard | One-Family Dwelling | Multiple-Family Dwellings | Townhouse Dwellings |
|---|---|---|---|
| Minimum Site Area | 6,000 sq. ft. | 7,500 sq. ft. | 7,500 sq. ft. |
| Lot Area Per Unit | 6,000 sq. ft. | 1,200 sq. ft. | 1,200 sq. ft. |
| Minimum Lot Width | 60 feet | 75 feet | 75 feet |
| Maximum Height (Feet) | 35 feet | 40 feet | 40 feet |
| Maximum Height (Stories) | 3 stories | 4 stories | 4 stories |
Special Exception and Modification Standards
Arlington County allows for increased height and density in the RA8-18 district under certain conditions, such as site plan approval or the provision of low-income housing [§6.3.4.C].
| Condition | Maximum Height | Density/Other Provisions |
|---|---|---|
| General Site Plan | 75 feet / 8 stories | Subject to County Board approval [§6.3.4.D.1.a] |
| Low/Moderate Income Housing | 60 feet | Up to 36 units per acre [§12.3.7.A] |
| Fort Myer Heights North Special District | 125 feet / 12 stories | Exclusive of mechanical penthouses [§6.3.4.D.1.b] |
| Large-Scale Housing (20+ Acres) | 95 feet / 10 stories | Maximum 25% coverage [§6.3.4.D.1.c] |
| Elder Care Uses | 75 feet | 600 sq. ft. lot area per unit [§6.3.4.C] |
Site Development and Parking Standards
Arlington County requires all developments in the RA8-18 district to provide adequate off-street parking based on the specific use of the property.
Parking Requirements
The RA8-18 district parking ratios are determined by the type of residential unit [§14.3.7].
| Use Type | Minimum Parking Requirement |
|---|---|
| One-Family Dwellings | 1 space per dwelling unit (2 if on a cul-de-sac) |
| Multiple-Family Dwellings | 1 & 1/8 spaces for each of the first 200 units; 1 per unit thereafter |
| Townhouses | 2 spaces per dwelling unit plus 1/5 space per unit for visitors |
| Hospitals | 1 space per 4 beds |
| Religious Institutions | 1 space per 5 sanctuary seats |
Setbacks and Placement
In the RA8-18 district, all structures must adhere to the placement regulations of Arlington County, which generally require a front setback of at least 25 feet from any street right-of-way line [§3.2.6]. For multiple-family dwellings specifically, building placement and additional setbacks from residential (R) districts are determined during the site plan approval process to ensure adequate light and air [§12.3.7].
Sections Cited
- §1.7.1 General Districts
- §3.2.6 Placement
- §6.1.2 Multiple-family (RA) Districts Principal Use Table
- §6.3 RA8-18, Multiple-family Dwelling District
- §12.3.7 Low- and Moderate-Income Housing
- §12.3.9 Recovery Residences
- §14.3.7 Required Parking and Standing Space