As housing affordability and limited inventory continue to challenge Northern Virginia, expanding housing options is an important part of the solution. In Fairfax County, proposed changes to accessory living unit (ALU) regulations offer an opportunity to increase housing availability while helping homeowners make better use of their existing properties. Fairfax County currently has some of the strictest ALU restrictions and regulations of any locality in the region and the proposed changes represent an opportunity to make progress towards expanding housing options.
What Are Accessory Living Units?
Accessory living units, also known as accessory dwelling units (ADUs), are secondary and subordinate living spaces associated with a primary residence. ALUs serve a variety of needs like providing housing options for young adults, older adults seeking to age in place, extended family members, and renters looking for additional choices in their communities. By making it easier to create these units, local governments can help expand housing opportunities without relying exclusively on new developments.
Understanding Fairfax County’s Proposed Changes
Fairfax County is considering changes to its ALU regulations that would expand opportunities for homeowners to establish these units on their properties. The proposed amendment attempts to streamline the process, remove unnecessary requirements, update the standards to align more closely with those of surrounding jurisdictions, and allow more lots the opportunity to have a detached ALU.
To accomplish this, the proposal would:
- Remove the renewal and permit recordation requirements for ALUs
- Revise the two-acre minimum lot size for a detached ALU to allow “by-right” development on lots 36,000 square feet or larger (special permits would be needed on all lots smaller than 36,000 square feet)
- Revise the maximum size requirement for both an interior and detached ALU to be 1,200 square feet or 40% of the principal dwelling, with a larger size allowed under special permit.
- Remove the owner occupancy requirement.
- Increase maximum occupancy of an ALU from two to three people.
- Remove the requirement to provide additional parking.
- Remove standards that are addressed by other codes and procedures.
NVAR has worked closely with Fairfax County staff and elected leaders in the development of this policy proposal and has supported this effort. However, under the proposed approach, a property would generally need to have at least 36,000 square feet of lot area to qualify for an ALU. While those under the threshold would be allowed using a “special permit” process, there is a general reluctance from owners and builders to undertake ALU projects that are subject to the uncertainty of a public hearing approval process–it is a known barrier to increased utilization.
That leaves only 14% of the homes in Fairfax County, those sitting on lots larger than 36,000 square feet, as the likely beneficiaries of the new ordinance. While this is an improvement over the two acre restriction, it is not good enough. The vast majority of properties would still not qualify under the proposed standard for an ALU without pursuing the special permit option. The proposed 36,000 square foot threshold is an arbitrary limitation that 86% of homes in the county fall below. NVAR urges Fairfax County to fully eliminate any minimum lot size requirements altogether.
While some residents may be concerned that expanded ALU regulations will lead to widespread construction of additional units across the county, expanding eligibility does not mean placing an ALU on every property. It means providing homeowners with more choices about their property and not constraining them to arbitrary limits. Ultimately, it would be a meaningful step towards expanding housing opportunities and bringing Fairfax County’s regulations in line with the broader region.
ALUs Are Part of a Broader Housing Supply Strategy
Expanding ALU opportunities aligns with NVAR’s NOVA Housing Supply Framework, a regional strategy developed in partnership with the Northern Virginia Chamber and the Northern Virginia Building Industry Association, and supported by groups around the region, to increase housing supply, improve affordability, and strengthen the region’s economic competitiveness.
The Framework recognizes that Northern Virginia needs a wider range of housing options to meet the needs of its residents and workforce. Zoning and land-use restrictions can limit the types of homes available, contributing to supply constraints and making it more difficult for people to find housing that fits their needs and budgets.
No single policy will solve the region’s housing challenges. However, expanding opportunities for ALUs can be one component of a broader approach to diversifying housing options, making more efficient use of existing residential properties, and helping more people find a place to call home.
Make Your Voice Heard: Upcoming Fairfax County Hearings
The proposed ALU changes represent an opportunity for Fairfax County to take meaningful steps toward expanding housing options. Public participation will be important as county officials consider the proposal and its potential impact on the community.
Want to make an even bigger impact? We have the opportunity to voice support for ALUs at two upcoming hearings. Community members, Realtors®, and housing advocates can make their voices heard either in person or by submitting written comments.
- Planning Commission — October 29
- Date/Time: Thursday, October 29, 2026, at 7:30 p.m.
- Location: Board Auditorium, 12000 Government Center Parkway, Fairfax, VA 22035
- Board of Supervisors — November 17
- Date/Time: Tuesday, Nov. 17, 2026
- 9:30 a.m. — Full Board of Supervisors meeting (Board Auditorium, Fairfax County Government Center, 12000 Government Center Pkwy., Fairfax, VA)
- 4:30 p.m. — Public hearing on the ALU zoning amendment
How You Can Participate
Attend in person: Join us at either hearing to show your support for policies that expand ALU opportunities and help address Fairfax County’s housing needs.
Planning Commission: Register to speak by clicking here
Board of Supervisors: Register to speak by clicking here
Submit written testimony: If you can’t attend in person, you can still make an impact by sending your comments directly to the appropriate county officials:
Planning Commission: plancom@fairfaxcounty.gov
Board of Supervisors: ClerktotheBOS@fairfaxcounty.gov
Be on the lookout for an upcoming call-to-action email with an easy way to lend your support in just a few clicks.
Expanding ALU opportunities is one important step toward addressing Northern Virginia’s housing supply challenges. Join NVAR in supporting thoughtful policy changes that create more housing options and help build a more attainable future for our communities.