WASHINGTON, NEW HAMPSHIRE · SULLIVAN COUNTY

BUILD AN ADU IN WASHINGTON.

✓ Allowed by-right · RSA 674:71-73

New Hampshire's HB 577 lets you add one accessory dwelling unit on your single-family lot in Washington — by-right. A detached ADU can be up to 950 sf, and ADU setbacks match your lot's single-family setbacks.

Washington setback reference

ADU setbacks in Washington follow your lot's single-family setbacks for its zoning district. Scan your address in the visualizer and we'll pull your exact parcel and confirm Washington's front, side, and rear requirements — or just ask us.

Note: Washington is beyond ~1 hour from our Madbury home base, so a travel-time allowance may be added — we'll spell it out in your quote.

Confirm your zoning

Washington zoning ordinance ↗NH GRANIT GIS (parcels & zoning) ↗

📍 SEE AN ADU ON YOUR WASHINGTON LOT →GET A QUOTE

Washington ADU FAQ

Can I build an ADU in Washington, NH?

Yes. Under NH RSA 674:71-73 (HB 577), one accessory dwelling unit is allowed by-right on single-family lots statewide, including Washington (Sullivan County). A detached ADU can be up to 950 sf.

What are the ADU setbacks in Washington?

ADU setbacks in Washington match your lot's single-family setbacks for its zoning district. We pull your exact parcel and confirm Washington's requirements before locking your price.