Arlington County R-20 One-Family Dwelling District Zoning Regulations
The R-20 district in Arlington County is a low-density residential designation that primarily permits one-family detached dwellings on large lots with a minimum area of 20,000 square feet. While the district is designed to preserve suburban residential character, it allows for a variety of public, civic, and accessory uses by-right or through special exception permits, while strictly prohibiting industrial and most commercial activities.
Density and Dimensional Standards
Development in the R-20 district of Arlington County must adhere to specific bulk and placement requirements to maintain the intended density of the neighborhood. The following table outlines the primary standards for all uses within the R-20 district.
| Type of Standard | R-20 Requirement |
|---|---|
| Minimum Lot Area | 20,000 sq. ft. [§5.2.3.A] |
| Minimum Lot Area per Dwelling Unit | 20,000 sq. ft. [§5.2.3.A] |
| Minimum Average Lot Width | 100 feet [§5.2.3.A] |
| Maximum Building Height | 35 feet [§5.2.3.A] |
| Maximum Lot Coverage (One-family dwelling) | 25% [§3.2.5.A] |
| Maximum Main Building Footprint Coverage | 16% [§3.2.5.A] |
Allowed Principal Uses
The Arlington County Zoning Ordinance categorizes uses as permitted by-right ("P"), requiring a use permit ("U"), or requiring site plan approval ("S"). If a cell is blank in the ordinance's use table, that use is prohibited in the R-20 district.
Residential Uses
- One-family Detached: Allowed by-right as the primary residential use type [§5.1.2].
- Recovery Residences: Allowed by-right for eight or fewer residents in one-family detached dwellings; larger facilities require a use permit [§5.1.2, §12.3.9].
- Expanded Housing Option (EHO) Development: Subject to specific requirements in §10.4, the Arlington County Zoning Administrator may permit duplexes, semidetached units, and small multi-family buildings (up to 6 units) within the R-20 district [§10.4.2].
Public, Civic, and Institutional Uses
Arlington County allows several non-residential uses within the R-20 district to support community infrastructure, most of which require a use permit to ensure compatibility with the residential surroundings.
| Use Type | Permission Level |
|---|---|
| Churches, mosques, synagogues, and temples | Permitted (P) |
| Minor Utilities (except bus shelters/bike share) | Permitted (P) |
| Schools (Elementary, Middle, or High) | Use Permit (U) |
| Libraries, Museums, and Art Galleries | Use Permit (U) |
| Hospitals | Use Permit (U) |
| Colleges and Universities | Use Permit (U) |
| Community Centers and Swimming Pools | Use Permit (U) |
| Child Care Centers | Use Permit (U) |
| Parks, Playgrounds, and Playfields | Use Permit (U) |
| Major Utilities | Use Permit (U) |
Commercial and Other Uses
Most commercial uses are prohibited in the R-20 district. However, the following specific exceptions are allowed under special conditions:
- Agricultural Uses: All agricultural uses are permitted by-right [§5.1.2].
- Bed and Breakfasts: Permitted only with a use permit and must be operated by a resident owner in a one-family dwelling [§5.1.2, §12.5.3].
- Open-Air Markets: May be allowed by use permit on properties with existing public or institutional uses [§12.5.17].
- Membership Clubs and Lodges: Allowed subject to a use permit [§5.1.2].
Accessory and Temporary Uses
Accessory uses in the R-20 district must be clearly incidental and subordinate to the principal one-family dwelling.
- Permitted By-Right (P): Accessory dwellings (subject to §12.9.2), family day care homes, family/caregiver suites, guest houses, home occupations (including accessory homestay), and private swimming pools [§5.1.4].
- Permitted by Use Permit (U): Commercial vehicle parking (subject to weight limits), crematoriums (accessory to cemeteries), and mortuaries/funeral homes [§5.1.4].
Prohibited Uses
Any use not explicitly marked as "P", "U", "C", or "S" in the Arlington County Residential Use Table is prohibited in the R-20 district [§5.1.2.D]. Prohibited uses include, but are not limited to:
- Retail and Service: All food establishments (restaurants, bakeries), retail sales (clothing, electronics), and vehicle sales/service [§5.1.2].
- Industrial: All light and heavy industrial manufacturing and production, except for recycling centers which may be allowed by use permit [§5.1.2].
- Wholesale: All wholesale trade and warehouse/freight movement operations [§5.1.2].
Parking Requirements
Arlington County mandates off-street parking for R-20 properties based on the location and type of dwelling.
| Use Type | Minimum Parking Requirement |
|---|---|
| One-family (Not on cul-de-sac) | 1 space per dwelling unit [§14.3.7.A] |
| One-family (Fronting cul-de-sac) | 2 spaces per dwelling unit [§14.3.7.A] |
| Accessory Dwelling | 1 additional space (if block is >65% parked) [§14.3.7.A] |
Sections Cited
- §3.2.5 Coverage
- §3.2.6 Placement
- §5.1.2 Residential (R) districts principal use table
- §5.1.4 Residential (R) districts accessory use table
- §5.2.3 R-20 Density and dimensional standards
- §10.4 Expanded Housing Option Development
- §12.3.9 Recovery Residences
- §12.5.3 Bed and breakfasts
- §12.5.17 Open-air markets
- §12.9.2 Accessory dwellings
- §14.3.7 Required parking and standing space