Building an ADU in Virginia: what state law allows

What the new state law does

Virginia passed SB 531 in 2026. The Governor approved it on April 13, 2026, as Chapter 895 of the Acts of Assembly, and it takes effect on July 1, 2027. The act numbered the new section 15.2-2292.3; the online Code of Virginia lists it as section 15.2-2292.4.

From that date, zoning ordinances for single-family residential districts "shall be deemed to include accessory dwelling units as a permitted accessory use." A locality can't add other requirements beyond those the law lists.

The law defines an ADU as an attached or detached unit on a residential lot that:

• Provides complete independent living facilities for one or more people
• Is on the same lot as an existing or proposed main home
• Has facilities for living, sleeping, eating, cooking and sanitation

[1][2][3]

Who the law doesn't cover

The law says "Nothing in this section shall apply to a locality that adopted an ADU ordinance prior to January 1, 2026." If your city, county or town already had ADU rules before 2026, its own ordinance still controls. Ask your local zoning office whether that exemption applies to you.

The law also doesn't apply to ADU permits a locality approved before July 1, 2027. The law also says it doesn't restrict a locality from passing its own ADU ordinance before that date if the ordinance "substantially complies" with the state law. [1]

What localities can still require

Under the state law, a covered locality may require:

• A lease term of 30 consecutive days or longer if you rent out the ADU
• Replacement of the main home's required parking if the ADU removes it, and dedicated parking for the ADU
• Limits on floor area, lot coverage and impervious area, but no lower than 350 square feet on lots under 2,500 square feet and 500 square feet on larger lots
• Compliance with building codes (including the Uniform Statewide Building Code), water, sewer, septic, emergency access, flood zone and stormwater rules, historic district rules, and Air Installations Compatible Use Zone limits
• Owner occupancy of the ADU or the main home, but not both, only at the time you apply
• That the ADU be no more than 500 feet from the main home
• No ADU on a lot that already has more than one dwelling unit
• No selling the ADU separately or subdividing it from the main home

[1]

What localities can't require

A covered locality may not require:

• Rear or side setbacks larger than the setback for the main home or for accessory structures on the lot, whichever is less
• Stricter rules than for single-family homes in the same zoning area for height, rear or side setbacks, lot size or coverage, or building frontage
• A restrictive covenant about the ADU on a lot zoned for a single-family home
• Public street improvements as a condition of allowing an ADU, except to repair a street the construction damages
• A family relationship between the people living in the ADU and the main home

[1]

The ADU permit and fee

You must "first obtain an ADU permit from the locality." The locality may charge no more than $500 for it. That fee is in addition to other fees, such as building, inspection or site permit fees.

The law says a locality "shall issue the permit" if you show that the ADU meets the state law and the local codes it refers to. For the general steps, see our ADU permit process guide. [1]

HOA rules and private covenants

The state law doesn't override private agreements. It says it doesn't "supersede or limit" recorded declarations and covenants, condominium instruments, common interest community declarations, cooperative instruments, or property owners' association declarations. If your home is in an HOA or condominium, check its rules before you plan an ADU. [1]

Medical cottages for a family member

A separate, older law lets a family caregiver install a "temporary family health care structure" for a relative who needs help with two or more activities of daily living, as certified by a Virginia-licensed physician. It is a permitted accessory use on lots zoned for single-family detached homes, without a special use permit.

• It must be transportable, assembled mostly off site, and no more than 300 gross square feet. It can't sit on a permanent foundation.
• Only one is allowed per lot, for one occupant (or a married couple, under conditions).
• You need a permit from the locality, which may charge up to $100, and the locality may check compliance each year.
• It must meet the main home's setbacks and be removed within 60 days after the person stops living there.

[4]

Where local rules differ

Until July 1, 2027, and in any locality that adopted an ADU ordinance before 2026, the state ADU section doesn't apply, so your city's or county's own zoning ordinance sets the ADU rules. Call your local zoning office to confirm which rules apply to your lot.

For more on costs and financing, see our guides to ADU costs and ADU financing. [1]

Virginia laws to know

• SB 531 (2026), Chapter 895, Va. Code 15.2-2292.4

  From July 1, 2027, makes ADUs a permitted accessory use in single-family zoning districts, caps the ADU permit fee at $500, and limits what localities can require. [1][2][3]

• Va. Code 15.2-2292.1 (temporary family health care structures)

  Lets a family caregiver place one small, temporary medical cottage of up to 300 square feet for an impaired relative as a permitted accessory use in single-family zones. [4]

Questions people ask