C-O Rosslyn: Mixed Use Rosslyn District Guide
The C-O Rosslyn zoning district in Arlington County is a high-density, mixed-use classification designed to foster a vibrant urban core with a base floor area ratio (FAR) ranging from 3.8 to 4.8. It permits a diverse range of office, retail, hotel, and multiple-family residential uses while enforcing a "peaks and valleys" skyline approach that can allow building heights to reach up to 470 feet above sea level through special exception approvals.
Purpose and General Character
The C-O Rosslyn district is established by Arlington County to encourage coordinated, high-density development within the Rosslyn Coordinated Redevelopment District as designated on the General Land Use Plan [Section 7.15.1]. The district is intended to advance the vision of the Rosslyn Sector Plan by creating a high-quality public realm focused on walkability and a robust network of parks and tree-lined streets [Section 7.15.1.B].
The general character of the C-O Rosslyn district is defined by:
- Diverse Mix of Uses: Integrating workplaces, housing, and visitor destinations [Section 7.15.1.A].
- Skyline Management: Implementing a "peaks and valleys" approach to building heights to preserve priority view corridors while creating an attractive skyline [Section 7.15.1.C].
- Multimodal Connectivity: Transforming the local transportation network into an enhanced system of "complete streets" that supports transit, pedestrians, and bicycle networks [Section 7.15.1.D].
- Architectural Excellence: Mandating superior architecture and urban design practices [Section 7.15.1.E].
Permitted Land Uses
Arlington County allows a variety of residential, public, and commercial uses within the C-O Rosslyn district, primarily through the site plan (Special Exception) process to ensure alignment with the Rosslyn Sector Plan.
Residential and Group Living
- One-family detached dwellings [Section 7.1.2].
- Multiple-family dwellings [Section 7.1.2].
- Recovery residences [Section 7.1.2].
- Assisted living facilities and nursing homes [Section 7.1.2].
- Continuing care retirement communities [Section 7.1.2].
Public, Civic, and Institutional
- Colleges and universities [Section 7.1.2].
- Community centers and libraries [Section 7.1.2].
- Churches, mosques, synagogues, and temples [Section 7.1.2].
- Schools (elementary, middle, and high) [Section 7.1.2].
- Hospitals [Section 7.1.2].
Retail, Service, and Commercial
- Hotels or motels [Section 7.1.2].
- Restaurants and artisan beverage facilities [Section 7.1.2].
- General retail (bakeries, drug stores, florists, etc.) [Section 7.1.2].
- Offices (professional, medical, and government) [Section 7.1.2].
- Indoor and outdoor recreation uses [Section 7.1.2].
Density and Dimensional Standards
The C-O Rosslyn district features two sets of standards: by-right standards for smaller developments and special exception standards for major mixed-use projects.
By-Right Standards
Development permitted by-right in the C-O Rosslyn district must adhere to the following requirements:
| Type of Standard | Single-Family Dwellings | All Other Uses |
|---|---|---|
| Minimum Lot Area | 6,000 sq. ft. | 20,000 sq. ft. |
| Minimum Lot Width | 60 ft. | 100 ft. |
| Maximum Height | 35 ft. | 35 ft. |
| Max Floor Area Ratio (FAR) | N/A | 0.40 to 0.60* |
*FAR for other uses varies by site area: 0.40 for up to 9,999 sq. ft.; 0.50 for 10,000-19,999 sq. ft.; 0.60 for 20,000+ sq. ft. [Section 7.15.3.A].
Special Exception (Site Plan) Standards
For major projects, the Arlington County Board may approve higher densities and heights [Section 7.15.3.B]:
| Use Type | Min. Lot Area | Min. Avg. Width | Max. Height (incl. penthouse/parapet) | Max. Floor Area Ratio (FAR) |
|---|---|---|---|---|
| Office/Retail/Service | 30,000 sq. ft. | 125 ft. | 153 ft. | 3.8 |
| Multiple-family | 30,000 sq. ft. | 125 ft. | 180 ft. | 4.8 |
| Hotel | 30,000 sq. ft. | 125 ft. | 180 ft. | 4.8 |
| Elder Care | 30,000 sq. ft. | 125 ft. | 180 ft. | 4.8 |
The County Board may approve density above 10.0 FAR and heights up to 470 feet above sea level if the project provides significant community benefits, such as Metrorail infrastructure improvements or affordable housing [Section 7.15.4].
Site Development and Parking
Arlington County requires that all C-O Rosslyn developments meet specific parking and streetscape standards to support the urban character of the district.
Parking Requirements
Parking regulations may be modified by the County Board during the site plan approval process, but typically follow these ratios [Section 7.15.5.A]:
| Use Category | Minimum Parking Requirement |
|---|---|
| Multiple-Family Dwelling | 1.0 off-street space per dwelling unit |
| Hotel | 0.7 off-street spaces per guest room and unit |
| Office/Retail/Service | 1 space per 530 sq. ft. to 1,000 sq. ft. of GFA* |
*The specific ratio for office/retail depends on the adequacy of the required Transportation Demand Management (TDM) plan [Section 7.15.5.A.1(c)].
All parking in the C-O Rosslyn district must be located below grade or within the structure housing the use [Section 7.15.5.A.2]. Additionally, short-term convenient parking must be provided for retail customers [Section 7.15.5.A.2(b)].
Sections Cited
- Section 7.1.2. Commercial/Mixed Use (C) Districts Principal Use Table
- Section 7.1.3. Commercial/Mixed Use (C) Districts Accessory Use Table
- Section 7.15.1. Purpose (C-O Rosslyn)
- Section 7.15.3. Density and Dimensional Standards
- Section 7.15.4. Provisions for Additional Density and Height
- Section 7.15.5. Site Development Standards