Accessory dwelling units, or ADUs, have become a popular housing option for homeowners in Arlington, VA, offering flexibility, affordability, and increased property value. Whether you’re looking to add a guest house, a rental unit, or a space for a family member, understanding Arlington’s regulations and benefits is key to making the most of your ADU project.
What Are Accessory Dwelling Units (ADUs)?
An accessory dwelling unit, or ADU, is a secondary housing unit on a single-family property. These can take many forms, like a basement apartment, a backyard cottage, or even an above-garage suite. ADUs are designed to provide additional living space, whether for family members, guests, or as rental units. Think of it as a smart way to maximize the space you already have, without needing to move.
Benefits Of Building An ADU
There are plenty of good reasons to add an ADU to your property. Here are a few of the top benefits:
- Extra Income: Renting out an ADU can be a great way to generate some additional income, whether you’re looking for long-term tenants or short-term rentals.
- Multigenerational Living: ADUs are perfect for families who want to keep loved ones close, like elderly parents or adult children, while still maintaining privacy and independence.
- Increased Property Value: Adding an ADU often boosts your property’s value. It’s an investment that can pay off in the long run, especially as demand for flexible living spaces grows.
- More Affordable Housing Options: ADUs provide an affordable housing solution, helping to ease the housing crunch in Arlington while blending seamlessly into residential neighborhoods.
Can You Build An ADU In Arlington, VA?
Yes, you can build an ADU in Arlington, but there are some specific guidelines and requirements you’ll need to follow. Arlington has worked hard to create regulations that allow homeowners to add ADUs while maintaining the charm and character of its neighborhoods. If you’re thinking about building one, it’s a good idea to start by understanding these rules.
ADU Requirements In Arlington
Before you break ground on your ADU, make sure you’re familiar with the local zoning laws and requirements. Here’s what you need to know:
Determining Property Eligibility and Code Consultation
Before you apply for an ADU permit, it’s vital to ensure your property and proposed ADU meet Arlington’s zoning requirements. Arlington County recommends scheduling a pre-submission meeting with the Zoning Division. During this meeting, you’ll receive information on:
- The eligibility of your property based on zoning.
- Requirements for adherence to the Virginia Uniform Statewide Building Code (VUSBC).
- Environmental considerations from the Department of Environmental Services (DES) and the Planning Division.
Eligibility Criteria for an ADU in Arlington
To be eligible for an ADU, your property must meet these criteria:
- Located in a district zoned R-20, R-10, R-8, R-6, R-5, R-10T, R-15-30T, or R-2-7. You can use Arlington’s Real Estate Assessments database to confirm your zoning, or ask your architect to do this for you.
- There can’t be another ADU or family/caregiver suite currently existing on the property. Arlington currently only permits one ADU per property.
Design Requirements for Detached ADUs in Arlington, VA
For ADUs located in an ADU constructed after May 18, 2019, the following design requirements must be adhered to:
- Height Restrictions: The height of any accessory building containing an ADU is limited to 1.5 stories or 25 feet, whichever is lesser.
- Footprint Limits: The footprint of an ADU in a detached building is restricted to 560 square feet in the R-5 and R-6 districts and 650 square feet in the R-20, R-10, R-8, R-10T, R-15-30T, and R2-7 districts.
- Setback Requirements: On interior lots, the accessory building must maintain at least 5 feet of rear and side yard setbacks. For corner lots, the rear yard setback must be at least 10 feet (to the eave), and the side yard setback must be at least 5 feet (to the wall).
- Proximity to Streets and the Main Dwelling: The nearest wall of an accessory building containing an ADU cannot be located closer than 25 feet to a street or the designated street right-of-way line. It also cannot be closer than 8 feet to the main dwelling.
For ADUs located in detached buildings constructed before May 18, 2019, these specific height, footprint, and setback restrictions do not apply. However, any alterations must be confined to the interior, in line with Arlington’s zoning ordinance.
Size Requirements for ADUs in Arlington, VA
The size of your ADU depends on the size of your main dwelling and the type of construction:
- If the main dwelling is at least 1,000 square feet, the ADU cannot exceed 35% of the combined floor area of the main dwelling and ADU, with a maximum size of 750 square feet.
- If the main dwelling is less than 1,000 square feet, the ADU can be up to 45% of the combined floor area, with a maximum size of 500 square feet.
When calculating the size of the ADU, it’s important to consider all floors, including the attic and basement, as part of the gross floor area (GFA) according to Arlington’s zoning ordinance.
Parking Requirements for ADUs in Arlington, VA
Arlington County has specific parking requirements for properties with ADUs:
- One Off-Street Parking Space: If your property has at least one off-street parking space, your ADU project is permitted.
- Two or More Off-Street Parking Spaces: If your property already has two or more off-street spaces, you must maintain at least two spaces.
- No Off-Street Parking: If your property has no off-street parking, you can still proceed with your ADU if one parking space is created, or if a parking study confirms that the block is less than 65% parked.
How Much Does It Cost To Build An ADU?
The cost of building an ADU can vary widely depending on size, design, and location. On average, in Arlington, you can expect to spend anywhere from $100,000 to $300,000, or more, depending on whether you’re going for a simple conversion (like a basement apartment) or a completely new detached structure. Don’t forget to factor in the costs of permits, design fees, and potential increases in property taxes.
While it’s an investment, the good news is that ADUs typically increase your property’s value and can generate rental income, making it a smart long-term financial decision.
Design Your Arlington ADU With A Residential Architect Today
If you’re ready to explore the possibility of adding an ADU to your Arlington home, a residential architect can guide you through the process. From navigating the permit system to designing a space that fits your needs and enhances your property, working with an expert can help ensure that your ADU not only complies with all local regulations but also enhances your home’s functionality and value.
Our team at Oztan Studio is a locally-based, premier residential architecture agency ready to assist you in bringing your backyard cottage dreams to life.
Whether you’re looking for a simple apartment over your garage or a standalone unit in your backyard, let’s talk about how we can make your vision a reality. Contact us today, and let’s get started on designing the perfect ADU for your home in Arlington!
