ADU builder · New York, NY

One more home, on the lot you already own.

Backyard ADUs, garage conversions, and basement, cellar and attic apartments for one- and two-family houses in Queens, Staten Island, Brooklyn and the Bronx. Design, DOB filing and construction from one team. Licensed and insured.

Check my lot

Finished attic room: An empty attic room with slanted beige walls, grey wood-look flooring, and a modern chande

How much does an ADU cost in New York City?

Published NYC figures are still scarce, because the city only began accepting ADU applications on September 30, 2025. One NYC ADU developer has estimated that backyard units and garage conversions start around $300,000 to $400,000, depending on size and complexity. Sprinklers, flood rules and utility work move the total. We quote in writing.

After a site visit you get a written, itemized quote. Read the NYC ADU cost guide.

Which ADUs can we build on an NYC lot?

Backyard ADUA new one-story home behind the house, up to 800 sq ft. Garage conversionAn existing garage rebuilt as a legal apartment. Basement or cellar ADUA unit below the main floor, outside flood risk areas. Attic ADUSpace under the roof turned into a sprinklered apartment.

Every project includes ADU design and DOB permits. First question for most owners: is my property eligible at all?

How does an ADU project work?

Step 1Lot checkZoning district, building type, flood maps and historic status.
Step 2Site visit and quoteWe measure, then price the job line by line.
Step 3Design and DOB filingPlans by a registered design professional, filed in DOB NOW.
Step 4Build and sign-offConstruction, inspections and the certificate of occupancy.

See every step of the process.

Which boroughs do we serve?

The ADU rules are citywide, but the housing stock is not. Detached and semi-detached houses are where most eligible lots are, and that changes the picture borough by borough.

QueensDetached and semi-detached homes inland, flood-mapped blocks by the bays.ADUs in Queens Staten IslandThe most detached houses, plus contextual zoning and a long shoreline.ADUs on Staten Island BrooklynRowhouses are out; freestanding homes and garages are in.ADUs in Brooklyn The BronxDetached homes in the north and east, waterfront rules on the Sound.ADUs in the Bronx

How NYC ADU rules apply across the boroughs.

Does your lot qualify for an ADU?

Send your address. We check the zoning district, building type, flood maps and historic status, then tell you which ADU types are possible. Queens, Staten Island, Brooklyn and the Bronx.