ADU Pass
Vienna
No County portion
Also in: Fairfax County
ADU Pass helps homeowners in Vienna, No County, Virginia navigate the permit paperwork for building an accessory dwelling unit. This area covers 1 ZIP code.
Map
ADU details
ADU legality: allowed-with-restrictions
Vienna is an incorporated town (population approximately 16,500) within Fairfax County, home to Wolf Trap National Park for the Performing Arts (the only US national park dedicated to performing arts), the Vienna/Fairfax-GMU Metro station (Orange Line terminus), and the W&OD Trail corridor. Vienna's town zoning controls inside town limits; Fairfax County's ALU framework applies just outside. SB531 (July 2027) will preempt the SUP requirement for one by-right ADU per single-family lot in both jurisdictions.
Cost scenarios
| Scenario | Sq ft | Permit | Build | Total |
|---|---|---|---|---|
| minimum | 300 | $2,800 | $162,000 | $164,800 |
| 600 | 600 | $3,200 | $336,000 | $339,200 |
| midpoint | 550 | $3,100 | $308,000 | $311,100 |
| maximum | 800 | $3,500 | $464,000 | $467,500 |
Fee breakdown (as of 2026-05)
Permitting process
Viability (permitted uses)
- Long-term rental: yes Long-term rental permitted with owner-occupancy of the primary dwelling. Strong demand from Vienna Metro station commuters, Wolf Trap visiting performers, and Tysons Corner office workers makes this the dominant practical use.
- Short-term rental: with-restrictions Vienna requires STR registration and lodging-tax remittance. Demand is strong due to Wolf Trap performances, DC/NoVA business travel, and proximity to Tysons Corner. STR enforcement is active.
- Office rental: no ADU must remain a dwelling unit; commercial use prohibited.
- Home office: yes Home occupation permitted under Vienna standards with limits on employee-visit traffic.
- Studio / workshop: yes Personal studio/workshop use is permitted accessory use.
- Agriculture: no Limited within town limits; small-scale gardening is permitted but livestock and commercial agriculture are prohibited.
- Relative support: yes Family-occupancy ADU is a common Vienna use case; multi-generational family housing for aging parents is a significant driver.
Incentives
Contacts
Utilities
- Water: Fairfax Water (Vienna purchases bulk water from Fairfax Water) · 30d connect · $5,500
- Sewer: Fairfax County Wastewater Management (via Vienna town sewer collection) · 30d connect · $7,200
- Electric: Dominion Energy Virginia · 28d connect · $1,800
- Gas: Washington Gas · 35d connect · $1,500
Property values & taxes
Construction timeline
Realistic total: best 9mo · typical 14mo · worst 20mo
Modular pathway inspectors are novice with modular
Vienna's dense residential streetscape constrains module placement; many lots have narrow front-yard access. Modules are uncommon in inner NoVA generally.
Financing
Insurance impact
HOA prevalence & preemption
Newer Vienna subdivisions (post-1980 condo communities, planned developments adjacent to the Metro station) are HOA-governed with their own ADU restrictions. Older single-family neighborhoods (Cedar Park, Hillside, Vienna Woods) are typically NOT in HOAs. SB531 (2027) does not preempt HOA private covenants.
Regulatory overlays (1)
- historic-district
Vienna has a designated historic district encompassing Church Street and adjacent Civil War-era structures; visible exterior alterations within this district may trigger Architectural Review Board compatibility review.
Technical envelope (climate & building code)
Climate & energy code
Building code
Amendments:
- Amendment
- Amendment
Contractor market (aggregate)
Legal history (timeline)
Current ordinance: Town of Vienna Zoning Ordinance, Article 8 (Accessory Dwelling Unit provisions), adopted varies-by-amendment, last amended 2024-XX-XX
- 1890-01-01 — Town of Vienna incorporated (town-incorporation)
Town of Vienna incorporated in 1890 following the arrival of the Washington and Old Dominion Railroad; the town developed as a streetcar suburb of Washington DC.
Effect: Established the town's independent zoning authority that persists today as one of the few incorporated municipalities within Fairfax County. - 2021-07-01 — Fairfax County Zoning Ordinance Modernization (zMOD) effective (county-ordinance)
Fairfax County's comprehensive zoning rewrite (zMOD) took effect, expanding Accessory Living Unit permission to most residential districts by administrative permit rather than special use permit.
Effect: Made ALUs significantly easier to permit in unincorporated Fairfax County parcels; did NOT affect Town of Vienna parcels which have their own ordinance. - 2026-04-14 — Virginia SB531 signed - statewide by-right ADU mandate (state-law)
Effective July 1, 2027: by-right one ADU per single-family lot statewide, $500 permit-fee cap, January 1, 2026 grandfather.
Effect: Will preempt Town of Vienna's SUP requirement for one by-right ADU starting July 1, 2027. Vienna's January 1, 2026 ordinance standards on setbacks and size are grandfathered.
Known issues (2)
- policy-review — Vienna Town Council faces active resident opposition to ADU densification; SB531 conformance amendments expected in 2026-2027 will likely include the most restrictive standards permissible under state preemption.
- other — Town/County jurisdictional ambiguity: Vienna town parcels are governed by Vienna's ordinance, but adjacent parcels (e.g., Tysons-edge or Oakton-edge) are unincorporated Fairfax County. Applicants frequently apply to the wrong jurisdiction initially; verify town limits via Vienna or Fairfax GIS.
County: no attribution (synthetic bucket)
No county
This city sits in the state's "no county" bucket — its ADU rules derive directly from state law and city ordinance without a county intermediary. No county-level sections apply.
Virginia state — ADU law and programs
State ADU law
Virginia has NOT enacted a statewide ADU preemption law. Virginia is a Dillon Rule state — localities possess only those powers expressly granted by the General Assembly — and the statutes granting zoning authority (Va. Code § 15.2-2280 et seq.) leave ADU regulation to local ordinances. ADU permission, setbacks, parking, size, and owner-occupancy rules therefore vary by county, independent city, and town. Virginia is unique in that it has 38 independent cities that function as counties (neither in nor subordinate to the surrounding county), meaning 'the county' for any given Virginia property may be an independent city rather than a true county. Several ADU preemption bills have been introduced in recent General Assembly sessions (2022 through 2025) without enactment; none have advanced past committee as of the Assembly's 2026 regular session adjournment.
State financing programs
Virginia does not operate an ADU-specific statewide loan, grant, or forgivable-loan program. Virginia Housing (formerly the Virginia Housing Development Authority, VHDA — rebranded 2020) administers general first-time-homebuyer, down-payment-assistance (DPA), mortgage-credit-certificate, and rehabilitation products that can be applied to ADU-adjacent purchases or improvements when eligibility criteria are met, but none target ADU construction as a distinct product. The Virginia Department of Housing and Community Development (DHCD) administers federal HOME and CDBG pass-through funds that local jurisdictions can direct toward ADU-adjacent rehab, but there is no state-level ADU-dedicated line item. Federally available products (FHA 203(k), Fannie Mae HomeReady and HomeStyle Renovation, Freddie Mac CHOICERenovation) remain the primary ADU financing path for Virginia homeowners.
State housing programs
Virginia does not run a state-level pre-approved-ADU-plan catalog, statewide impact-fee-waiver statute for ADUs, or streamlined-review mandate. State-level programs that touch ADU-adjacent policy are coordinated primarily through the Department of Housing and Community Development (DHCD) and Virginia Housing, and act by funding or assisting local jurisdictions rather than by preemption. Local ADU activity — Arlington County's Accessory Dwellings program (detached ADUs permitted since 2008, liberalized 2020), Alexandria's accessory-dwelling ordinance, Fairfax County's accessory-living-unit program, and Charlottesville's 2021 zoning-code changes — is authorized under the localities' Va. Code § 15.2-2280 zoning authority, not by state mandate.
- DHCD Community Development Block Grant (CDBG) Program — Federal CDBG funds administered by DHCD to eligible non-entitlement Virginia localities for community-revitalization, housing-rehab, and infrastructure projects. Not ADU-specific. Participating localities can direct CDBG funds toward housing-rehab projects where local policy supports ADUs.
- DHCD HOME Investment Partnerships Program — Federal HOME funds administered by DHCD to Virginia participating jurisdictions and non-profits for affordable-housing acquisition, rehab, and new construction. Not ADU-specific; can be directed to ADU-adjacent rehab at local discretion.
- Virginia Housing Commission — Permanent advisory commission of the General Assembly that studies housing-policy questions and recommends legislation. Has periodically studied ADU preemption and missing-middle housing without recommending statewide enactment as of 2026-04-21.
- Local ADU ordinances under Va. Code § 15.2-2280 authority — Not a state program — listed here because Virginia ADU policy is executed entirely at the locality level under the § 15.2-2280 zoning grant. A homeowner seeking to build an ADU consults the zoning ordinance of the specific county, city, or town where the parcel is located.
Federal (United States) — ADU-relevant rules and programs
Federal ADU law
The United States has no federal statute that directly regulates accessory dwelling unit entitlement or design. Land-use authority over ADUs resides with states and local governments under the traditional police power. Federal engagement is limited to financing (Fannie/Freddie/FHA/VA/USDA), flood insurance (FEMA/NFIP), and discretionary housing programs (HUD), which are recorded in sibling sections of this file.
Federal financing programs
Federal housing-finance agencies and GSEs set nationwide underwriting rules that govern whether an ADU can be financed, appraised, and counted toward mortgage qualifying income. The relevant actors are Fannie Mae, Freddie Mac, FHA (HUD), VA, and USDA Rural Development.
Federal tax credits
There is no ADU-specific federal tax credit. ADUs may incidentally qualify for existing federal energy-efficiency and clean-energy tax credits when the ADU construction includes qualifying measures.
Federal housing programs
HUD administers several discretionary programs that can fund ADU-related activity at the grantee's election, but none is an ADU-specific program.
ZIP Code
- 22183
Post Office
- 200 Lawyers Rd NW, 22180
- 8150 Leesburg Pike Ste 180b, 22182
Locale Names
- Tysons Self Serv Po