West Hartford, CT Accessory Structures: ADU Rules (2026)

Section 177-23.1A permits one accessory dwelling unit, subordinate and incidental to the principal dwelling, on a lot in any one-family residence district, with its own kitchen, bathroom and sleeping facilities. The lot must meet the district's minimum lot size, and the unit's gross floor area is capped at 1,000 square feet or 30% of the principal dwelling's gross floor area, whichever is less, under a limit amended in 2023. A detached accessory dwelling unit must observe the principal dwelling's side and rear yard setback or 10 feet, whichever is less, and basements are off-limits unless one wall opens fully to grade with both windows and a walk-out door.

Design standards require the unit to preserve the one-family character of the property: matching or complementary exterior materials and roof shapes, and window and door placement that protects neighbors' privacy. At least one off-street parking space must be added under Section 177-32 without reducing the principal dwelling's required parking, and no new curb cuts may serve the unit. Every application goes through site plan review under Section 177-42B, with mailed notice to adjoining owners and a posted sign on the property, and the unit must still separately satisfy every applicable building, health, fire and sanitary code.