Fairfax County staff propose tiered rules for accessory living units; residents raise parking and character concerns

Fairfax County planning staff presented proposed changes to the county’s zoning rules for accessory living units on a community call, describing a tiered approach they say would allow more detached units on larger lots while keeping controls on smaller parcels.

Casey Judge, project lead, opened the meeting and said the amendment aims “to clarify and update the regulations to make sure that we can reduce the number of interpretations” by staff and “remove impediments and barriers to get legally ALUs established.” Carmen Bishop, co‑lead, summarized staff’s white paper and recommended options including folding zoning review into the building permit process so a separate administrative zoning permit would not always be required.

Why it matters: Staff framed ALUs as a flexible, lower‑cost housing option for older adults, young professionals and caretakers and as a potential supplemental income source for homeowner‑builders. They said clearer rules would reduce discretionary interpretations and speed lawful establishment of units.

Key elements of the proposal: Staff recommended allowing detached ALUs by right (or without a separate administrative zoning permit) on lots of at least 36,000 square feet; permitting detached units by special permit on lots between 15,000 and 36,000 sq ft; and prohibiting detached ALUs on lots smaller than 15,000 sq ft. The draft retains a 1,200‑square‑foot maximum for detached units but would give the Board of Zoning Appeals the discretion to approve larger sizes in limited cases. For lots under 36,000 sq ft staff would keep a 20‑foot height limit for accessory structures and proposed a 35‑foot maximum on larger lots, with the caveat that accessory structures remain subordinate to the principal dwelling. Staff also proposed increasing total ALU occupancy from 2 to 3 persons (keeping a two‑bedroom limit) and presenting 4 persons as an option for board consideration.

Permitting and parking: Bishop told attendees that removing the administrative permit could streamline approvals but would make tracking the number of ALUs more difficult. Staff recommended not requiring an additional parking space specifically for an ALU beyond the existing parking required for the dwelling, and noted recent state legislation limits the county’s ability to mandate an extra space in certain designated areas.

Public questions and concerns: During an extended Q&A, residents raised recurring themes. Several asked whether interior kitchens or a second kitchen automatically make a space an ALU and how the county enforces illegal conversions; staff said residences using an interior kitchen as a primary residence typically trigger ALU rules and that permit records can be searched in the county’s planning system. Others worried about neighborhood character and curbside parking. “It seems like a slippery slope,” said Elaine, who asked whether allowing ALUs widely would effectively convert single‑family lots into duplex‑style occupancy. Staff replied regulations (size, bedroom and occupancy caps and the accessory requirement) are intended to prevent that conversion.

Owners and builders: Some participants urged fewer special permits and broader by‑right allowances to accelerate housing supply. Keith said the tiered approach still excludes large portions of land and that mandatory special permits for many lots would delay construction; staff estimated a special‑permit project could take roughly six months from submittal to public hearing but noted timelines vary.

State law and local discretion: One attendee asked whether recent state legislation supersedes local rules; staff replied that the county’s existing ALU ordinance allows Fairfax to continue to apply its regulations even after state action, and that staff included the state rules as a comparison in the white paper.

Next steps: Staff said the white paper, draft text and presentation slides will be posted online, and they demonstrated a community toolkit for group feedback. They encouraged residents to submit comments to staff, the planning commission and the board ahead of public hearings planned before year‑end.

The meeting closed with staff directing participants to email and subscription links for updates. No formal votes or motions were taken at the meeting.