What NYC Real Estate Agents Need to Know About ADUs in 2026

Aug 21

New York City’s ADU laws are brand new, and as a result, most property owners, investors, and real estate agents are completely unaware of the impact ADUs will have on the housing market, especially in Queens and Staten Island. ADUs are incredibly popular in California, Washington, Oregon, and other parts of the Western US, and there is no doubt that NYC will embrace this rapidly-growing housing trend.

Real estate agents who know how to recognize and market a property’s ADU potential will gain a massive competitive edge over uninformed agents.

What is an ADU and Why Do They Matter for Your Business?

In NYC, Ancillary Dwelling Units, otherwise known as Accessory Dwelling Units or ADUs, are legal dwelling units built in addition to a one- or two-family home, and can be standalone (detached) backyard units, additions to the primary home, or basement and attic conversions. ADUs are valuable because of the flexibility they provide to property owners, allowing homeowners to generate rental income, accommodate extended family members, or create a new home office.

New York City legalized ADUs under Local Law 127 in December 2024, and as of September 30, 2025, the DOB is accepting ADU permit applications. In March 2026, the city launched the ADU for You platform with pre-approved ADU designs and other resources for property owners.

Most homeowners have no idea that ADUs are legal and whether their property is eligible for an ADU. Neither do most agents.

That knowledge gap is your opportunity.

Clients who are considering whether to sell, refinance, or hold onto their one- or two-family home now have a new question to answer first: Can this property generate an extra $1,500 - $3,500 per month in ADU rental income? The answer changes the calculus on almost every one- and two-family home transaction.

Aspiring homeowners and investors are always on the hunt for great deals, and they value agents who can find undervalued properties. Conversely, sellers value agents and brokers who can find creative ways to successfully market their properties.

How to Identify ADU-Eligible Properties

Not every property qualifies, but many do. The basic eligibility criteria under NYC Zoning and Building Code rules:

Property type: One- or two-family home
Zoning: Must be in an eligible residential zoning district (R1-R6 generally) and have sufficient remaining buildable Floor Area
Lot: Must have sufficient space for the ADU type being proposed
DEP Flood Zone: Properties located in DEP’s Flood Zones have fewer ADU options, especially 2-family homes.

In 2026, there are many different online tools for checking ADU eligibility. Our favorite online tools include the city’s ADU for You platform and NYC Zoning AI’s ADU platform. Both of these platforms allow users to enter an address and receive instant eligibility determination. Run this check on every 1-2 family listing before you price it.

Instant eligibility tools have limitations and should be used as an initial screening tool only. Further research by qualified professionals – zoning experts and licensed architects – must be performed to confirm ADU eligibility.

Second Key’s free ADU assessment works a little differently than the free online tools. When you request a free assessment, we not only review the property’s zoning characteristics – we also provide individualized recommendations and considerations to help you understand whether the project is worth pursuing.

Talking Points for Sellers

When listing a 1-2 family home in Queens, Staten Island, Brooklyn or the Bronx, check for ADU eligibility before setting the price. If the property qualifies for an ADU, consider:

Marketing the “ADU-eligible” status explicitly in the listing description
Including a rough estimate of ADU rental income potential in your pitch
Recommending a free assessment from a firm like Second Key before the listing goes live – so you can be certain you’re marketing the right information

Sellers who can say “this home comes with the potential to generate $2,500/month in additional income” have a fundamentally different story to tell.

Talking Points for Buyers

First-time buyers are getting priced out of NYC. But a two-family or ADU-eligible home in Queens or Brooklyn at $750,000 looks very different if the ADU generates an extra $20,000 - $30,000 of rental income per year that can offset mortgage payments. Help your buyers model the numbers and find “hidden gems”.

Investor buyers are even more straightforward: ADUs increase yield on existing properties without requiring a full rehab. For any client holding a 1-2 family as a rental property, an ADU is a capital improvement that generates income and creates return on investment.

The Referral Opportunity

Second Key offers a referral partnership program for NYC real estate brokers and agents. When you refer a homeowner who becomes a client, you earn a referral fee.

More importantly, offering ADU expertise positions you as a resource – not just a transaction. Clients remember agents who gave them information that changed the economics of their decision. That’s how referrals happen.

If you’re regularly selling 1-2 family homes in Queens, Staten Island, Brooklyn and the Bronx, let’s talk about how we can help each other. Contact us to set up an appointment.

What to Know About the ADU Build Process

When clients ask you how long it takes or how much it costs to build an ADU, here’s a reliable answer:

Cost: $75,000 - $275,000, depending on ADU type and size
Permit timeline: 3-6 months with the DOB
Construction timeline: 3-6 months post-permit
City assistance: Up to $395,000 available through the Plus One ADU program for eligible homeowners

Second Key handles everything from initial eligibility screening to final Certificate of Occupancy, and we measure our success by our client’s success.

Stay Ahead of the Market

The agents who win in this market are the ones who can answer the question before the client thinks to ask it. Knowing ADU eligibility and marketability isn’t a niche skill anymore – it’s crucial for anyone buying and selling 1-2 family homes in the outer boroughs.

Partner with Second Key

At Second Key, we are paving the way for NYC’s new ADU movement. Whether you are looking for unique ways to maximize your client’s property value or you want to help your clients purchase undervalued properties, we are ready to offer our expertise.

Nim Ginsburg