Maisel House
Reform Architecture PLLC
Your starting
place for
building an ADU
in NYC.
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What is an Ancillary Dwelling Unit (ADU)?
An Ancillary Dwelling Unit (ADU), also known as an Accessory Dwelling Unit, is a small building on the same lot as your main house, like a backyard cottage, basement apartment, garage conversion, or attached addition.
Find your design.
Our Pre-Approved Plan Library offers Rear Yard ADU designs already reviewed by the NYC Department of Buildings for faster approvals and fewer surprises.
Choose a design, work with a Registered Design Professional (RDP) to adapt it to your lot, and submit permits without a full design review.
Process
1
Check Your Eligibility
Search your address to find out if your lot allows an ADU.
2
Determine Your ADU Goals
Identify your reason for building an ADU, whether extra space, rental income, or added value.
3
Plan Your ADU
Choose a pre-approved or custom design and determine your budget.
4
Build Your ADU
Follow your plan, stay in touch with your team, and see your ADU take shape from foundation to finish.
5
Prepare to Move In
Finish all the requirements that ensure your ADU is approved for occupancy before moving in or renting it.
5
Prepare to Move In
Finish all the requirements that ensure your ADU is approved for occupancy before moving in or renting it.
1
Check Your Eligibility
Search your address to find out if your lot allows an ADU.
2
Determine Your ADU Goals
Identify your reason for building an ADU, whether extra space, rental income, or added value.
3
Plan Your ADU
Choose a pre-approved or custom design and determine your budget.
4
Build Your ADU
Follow your plan, stay in touch with your team, and see your ADU take shape from foundation to finish.
5
Prepare to Move In
Finish all the requirements that ensure your ADU is approved for occupancy before moving in or renting it.
1
Check Your Eligibility
Search your address to find out if your lot allows an ADU.
Need help or have questions?
Neighborhood Restore and its affiliate, Restored Homes HDFC, offer free technical assistance to help New York City residents plan, finance, and build legal ADUs.
You can call their ADU hotline at 212-584-8981 ext. 12 or reach out via email at aduforyou@neighborhoodrestore.org
Can I build an ADU on my property?
Enter your address to see what type of ADU is possible on your property.
