C-O-A Mixed Use District Guide: Arlington County
The C-O-A district in Arlington County is established to foster coordinated mixed-use developments, specifically integrating office, multiple-family residential, and hotel uses in close proximity to Metrorail stations. Development within the C-O-A district is characterized by high-density structures, with building heights reaching up to 216 feet and Floor Area Ratios (F.A.R.) scaling up to 6.0 based on site size. All major developments in this district require site plan approval to ensure consistency with the Arlington County General Land Use Plan.
Purpose and General Character
The primary purpose of the C-O-A, Mixed Use District is to encourage the coordinated redevelopment of sites near Metrorail stations. To be eligible for this zoning designation, a site in Arlington County must be located within an area identified for "coordinated mixed use development" on the General Land Use Plan. The Arlington County Board determines the specific types and densities of allowed uses based on the site's characteristics, its location, and the provision of community facilities, open spaces, and landscaping [§7.14.1].
Permitted Land Uses
The C-O-A district allows for a variety of residential, commercial, and institutional uses. While some uses are permitted by-right, the majority of high-intensity developments require a special exception via site plan approval.
Residential Uses
- One-family detached dwellings: Permitted by-right [§7.1.2].
- Multiple-family dwellings: Permitted by site plan approval [§7.1.2].
- Townhouses: Permitted by site plan approval [§7.1.2].
- Recovery Residences: Permitted by-right if serving eight or fewer residents, or by use permit if serving more [§12.3.9].
Public, Civic, and Institutional Uses
- Churches, mosques, and temples: Permitted by-right [§7.1.2].
- Schools (elementary, middle, and high): Permitted by use permit [§7.1.2].
- Libraries, museums, and art galleries: Permitted by use permit [§7.1.2].
- Hospitals: Permitted by site plan approval [§7.1.2].
Commercial and Retail Uses
In the C-O-A district, most retail and service uses are permitted by-right when located within a building that has been approved through a site plan [§7.1.2.A].
- Offices (Medical, Professional, and Government): Permitted by site plan approval [§7.1.2].
- Hotels and Motels: Permitted by site plan approval [§7.1.2].
- Restaurants and Bakeries: Permitted by-right [§7.1.2].
- Grocery Stores and Drug Stores: Permitted by-right [§7.1.2].
- Animal Boarding and Veterinary Clinics: Permitted by-right or site plan depending on specific operations [§7.1.2].
Density and Dimensional Standards
The C-O-A district utilizes a sliding scale for density and height. As the total site area increases, the permitted Floor Area Ratio (F.A.R.) and maximum building height also increase.
Special Exception Height Limits
The following table outlines the maximum building heights permitted under special exception site plan approval [§7.14.3.B.2]:
| Site Area (sq. ft.) | Office and Hotel Max Height (feet) | Multiple-family and Elder Care Max Height (feet) |
|---|---|---|
| 19,999 or less | 100 | 151 |
| 20,000 to 29,999 | 110 | 162 |
| 30,000 to 39,999 | 120 | 171 |
| 40,000 to 49,999 | 130 | 180 |
| 50,000 to 59,999 | 140 | 189 |
| 60,000 to 69,999 | 150 | 198 |
| 70,000 to 79,999 | 160 | 207 |
| 80,000 or more | 170 | 216 |
Note: The Arlington County Board may approve site plans that exceed these limits by up to 30 feet under specific circumstances [§7.14.3.B.2(b)].
Density (Floor Area Ratio)
Density is calculated based on the total site area and the proposed use mix [§7.14.3.D.3]:
| Site Area (sq. ft.) | Total Floor Area Ratio (F.A.R.) | Max Office, Hotel, and Commercial F.A.R. |
|---|---|---|
| 4,999 or less | 1.0 | 0.5 |
| 5,000 | 1.5 | 0.75 |
| 10,000 | 2.0 | 1.0 |
| 15,000 | 2.5 | 1.25 |
| 20,000 | 3.0 | 1.5 |
| 30,000 | 3.5 | 1.75 |
| 40,000 | 4.0 | 2.0 |
| 50,000 | 4.5 | 2.25 |
| 60,000 | 5.0 | 2.50 |
| 70,000 | 5.5 | 2.75 |
| 80,000 or more | 6.0 | 3.0 |
Density Bonuses and Conditions
- Multiple-family Bonus: An additional 0.5 F.A.R. may be approved for any project in the C-O-A district that is at least 90 percent committed to multiple-family residential use [§7.14.3.D.3(c)].
- Hotel Retail Requirement: Buildings where the primary use is a hotel must dedicate 50 percent of the ground floor gross floor area to retail use, unless the County Board approves otherwise via site plan [§7.14.3.D.3(e)].
Site Development Standards
Setbacks
Structures in the C-O-A district must adhere to specific street setbacks to maintain the urban character of the Metrorail corridors [§3.2.6.A.1]:
- Street Setback: 50 feet from the centerline of any street.
Parking Requirements
Arlington County mandates specific off-street parking ratios for the C-O-A district, which may be modified during the site plan review process [§7.14.5.B]:
| Use Type | Required Parking Spaces |
|---|---|
| Multiple-family Dwelling | 1.0 space per dwelling unit |
| Hotel | 1.0 space per hotel unit |
| Commercial/Office | 1.0 space per 530 sq. ft. of GFA* |
*Note: If the commercial use is part of a project with associated multiple-family use, the requirement changes to one space per 580 sq. ft. of GFA [§7.14.5.B.2].
Landscaping
A minimum of 10 percent of the total site area must be dedicated to landscaped open space in accordance with Arlington County's general landscaping standards [§7.14.5.A].
Sections Cited
- Section 3.2.6: Placement (Setbacks)
- Section 7.1.2: Commercial/Mixed Use (C) Districts Principal Use Table
- Section 7.14: C-O-A, Mixed Use District
- Section 12.3.9: Recovery Residences
- Section 14.2: Landscaping
- Section 14.3: Parking and Loading