Straight answers from the team that handles design, permitting and construction every day.
Can I convert my attached garage into an ALU?
Often, yes. In Fairfax, a garage with an interior connection to the home is generally reviewed like other interior ALUs, and Arlington allows interior units and converting existing detached garages. Loudoun and Prince William depend on zoning. Detached garages face more restrictions that vary by county. We confirm the path for your address first, including whether required parking must be replaced.
What is the difference between converting a basement and a garage?
Both can become a legal rental unit. Basements typically cost $60,000 to $150,000 and are already inside the home. Attached garage conversions typically cost $90,000 to $200,000 and can offer more natural light, but need slab, insulation, heating and cooling, and fire-separation work. We evaluate both during your consultation.
How much does it cost to convert a basement or garage into a rental unit?
Basement conversions typically run $60,000 to $150,000 and attached garage conversions $90,000 to $200,000, depending on size, finishes and site conditions. Northern Virginia 1BR apartments average roughly $2,000 to $2,400 a month, and actual ALU rent varies. Use the calculator above for your own payback estimate.
Do I have to wait until 2027 to build a basement or garage ALU?
No. SB531 takes effect July 1, 2027, but it does not stop ALUs built under current local rules. Fairfax and Arlington already allow them, and Loudoun's ordinance provides for accessory dwellings. Where rules are more restrictive today, you can start design and permitting planning now. We confirm what your county allows before you commit.
What does Virginia SB531 mean for basement and garage conversions?
SB531, signed April 13, 2026 and effective July 1, 2027, requires localities to treat ADUs as a permitted accessory use in single-family zones and caps permit fees at $500. It also bars requiring occupants to be related. Localities that already had an ADU ordinance before January 1, 2026 keep their own rules, and HOA covenants still apply.
Can I rent my ALU to anyone?
Under SB531, localities it covers cannot require occupants to be related to you. In Fairfax, ALU occupancy limits (currently two people) apply to owners and renters alike. Arlington has its own occupancy and owner-occupancy rules. We review the rules for your county and address.
Do I need to live in the home to have a rental unit?
Often yes today. Fairfax currently requires the owner to live in the main home or the ALU, though a staff proposal would remove that requirement; hearings are October 29 and November 17, 2026. Arlington also requires an owner to occupy a dwelling on the property. Confirm Loudoun and Prince William for your zoning.
Does my HOA have to allow an ALU if the county permits it?
No. SB531 does not override HOA or condo covenants, and county zoning does not either. If your HOA prohibits secondary units or rentals, that restriction can still apply. We review HOA documents as part of your consultation.
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How long does the permit process take?
It depends on the county and project. In Fairfax, interior ALUs are approved administratively without a public hearing. Projects that need a special permit, Health Department review for well or septic, or extra site plans take longer. We give a county-specific estimate at your consultation.
Can a basement or garage ALU have a stove or oven?
Yes. An ALU needs complete kitchen facilities, and cooking appliances, ventilation and fire separation follow the Virginia building code and your county's review. A converted garage needs fire separation from the main house. We design to code and handle the permit set.
Can I use Airbnb for my ALU?
Plan on long-term tenants. In Fairfax, short-term lodging such as Airbnb is not allowed on a property with an ALU, and short-term rentals are regulated separately elsewhere. Check your county and HOA before listing a unit.
