How building an ADU in NYC works.
Haven runs the whole process. Consultation, design, engineering, permitting, and construction under one roof, so you have a single point of contact from your first call through your certificate of occupancy.
A free consultation call.
It starts with a conversation. We learn about your property, your goals for the space, and your budget. You leave the call with a clear-eyed read on whether an ADU makes sense for your lot, and what the path forward looks like.
- Zoning sanity check on your address
- What size and configuration your lot supports
- Realistic budget and timeline expectations
Feasibility study & ZRD-1
A few lots hit edge cases in the zoning code: a merged zoning lot, a non-conforming use, an irregular shape. When that happens, we file a ZRD-1 (Zoning Resolution Determination) to get the Department of Buildings’ formal read before you invest in full design. If your lot needs it, we’ll flag it on the call.
Site evaluation and preliminary design.
Whether you’re building for rental income or a place for family, we work with you to custom-design an ADU that maximizes your space and value. Our team visits the property, measures the lot, and drafts the first version. You walk away with the documents you need to make an informed decision.
- Site plan showing setbacks, lot coverage, and placement
- Floor plan tailored to your backyard and use case
- Exterior and interior renderings
- Cost estimate from our construction partner
- A full proposal for the project, end to end
Detailed design and engineering.
We take the preliminary design as the starting point and develop it into the real thing. Layouts get refined, finishes and fixtures get selected with you, and structural and MEP engineering coordination happens in parallel, so the design is fully resolved and buildable before it ever goes to the city.
- Refined floor plans and elevations developed from the preliminary set
- Finish palettes, cabinetry, appliances, and fixtures selected with you
- Structural and MEP engineering coordinated into the drawings
- Lighting plan and millwork details resolved
We handle the permits.
This is the part most homeowners dread, and the part we take entirely off your plate. Haven hires and manages every licensed professional required to get your ADU through the NYC Department of Buildings, so you stay on a single contract with us instead of juggling four.
- Architects: stamped construction document set, ready to file
- Structural engineer: foundation and framing calculations
- MEP engineer: plumbing, electrical, and mechanical design
- NYC-registered expediter: DOB NOW: Build filing and follow-up
- Objections and resubmissions handled until your permits are approved
Construction begins.
Our contractor team breaks ground in your backyard. A site supervisor runs the project day to day; you get weekly progress updates and a single point of contact at Haven. When the last inspection clears, you get the keys.
- Vetted contractor crew with NYC experience
- Weekly progress photos and updates
- Final DOB inspections and certificate of occupancy
- Walkthrough and handoff when complete
One team, start to finish. From your first call to the keys.
Consultation, design, engineering, permitting, and construction. Haven runs every step so you end up with a finished home in your backyard, not a stack of subcontractor invoices.
Building an ADU in NYC, answered.
How do you build an ADU in NYC?
Building an accessory dwelling unit (ADU) in New York City follows five steps: a free consultation call, a site evaluation and preliminary design, detailed design and engineering, permitting through the NYC Department of Buildings via DOB NOW: Build, and construction. Haven manages all five, including hiring the architects, structural and MEP engineers, and the NYC-registered expediter, so you have one point of contact from the first call to your certificate of occupancy.
What do I receive after the site evaluation and preliminary design?
You receive a site plan showing setbacks, lot coverage, and ADU placement; a floor plan tailored to your backyard and use case; exterior and interior renderings; a cost estimate from Haven’s construction partner; and a full proposal for the project end to end.
Do I need a ZRD-1 or feasibility study for my ADU?
Most lots do not. A ZRD-1 (Zoning Resolution Determination) is a formal ruling from the NYC Department of Buildings, used when a lot hits an edge case in the zoning code such as a merged zoning lot, a non-conforming use, or an irregular shape. If your lot needs one, Haven flags it on the consultation call and files it before full design begins.
Who handles the DOB permit, the architects, and the engineers?
Haven does. We hire and manage every licensed professional required to permit your ADU: the architects who prepare the stamped construction document set, the structural engineer for foundation and framing calculations, the MEP (mechanical, electrical, plumbing) engineer, and a NYC-registered expediter who files through DOB NOW: Build and handles objections and resubmissions until your permits are approved.
Can I customize the ADU design and finishes?
Yes. During detailed design and engineering, Haven develops the preliminary design into the final construction drawings and selects finishes, cabinetry, appliances, fixtures, and lighting with you. Whether you are building for rental income or a home for family, the ADU is custom-designed to maximize your space and value.
What happens during ADU construction?
A vetted contractor crew breaks ground in your backyard and a site supervisor runs the build day to day. You get weekly progress updates and a single point of contact at Haven throughout. The project closes with final DOB inspections, a certificate of occupancy, and a walkthrough and handoff of the finished home.
How do I know if my property qualifies for an ADU in NYC?
Use Haven’s free NYC ADU eligibility tool. Enter your address and it checks your zoning district, lot geometry and setbacks, Floor Area Ratio, and flood and historic-district overlays against the City of Yes for Housing Opportunity rules, then returns a feasibility report covering up to four ADU types.