New Jersey's Fourth Round: What It Means for Developers Right Now
A New Rulebook for Affordable Housing
New Jersey's affordable housing framework got a real rewrite with the A4 legislation, and developers who haven't looked closely at what it means for site selection are behind. The Fourth Round covers obligations from 2025 through 2035, a full decade, and it changed how those obligations get calculated and enforced across all 564 municipalities.
The state's Department of Community Affairs published every municipality's calculated obligation number on October 20, 2024. From there, towns had to adopt a Housing Element and Fair Share Plan with draft ordinances by June 30, 2025, and then amend and formally adopt implementing ordinances by March 15, 2026.
What This Means If You Missed the Announcement
Municipalities that missed those deadlines risk losing their immunity from builder's remedy lawsuits, which is the legal mechanism that lets a developer sue a town directly for zoning approval when the town hasn't met its affordable housing obligation. That immunity is the thing towns want most, and it's also the reason most of them did adopt ordinances on schedule. But not every town made both deadlines cleanly, and where they didn't, new legal and rezoning activity is opening up in towns that weren't previously seen as development opportunities.
For a developer, the practical result is straightforward. Municipalities across NJ are working through rezoning and inclusionary overlay processes right now, through 2035, to satisfy Fourth Round numbers. That's a decade-long pipeline of sites becoming buildable or upzoned in towns that hadn't planned for density before.
Why Feasibility Work Matters Before You Have a Site Under Contract
The obligation numbers and ordinance language differ town to town, and the density, height, and inclusionary percentage a site can support is not something you learn from a zoning map alone. Two towns with similar Fourth Round numbers can arrive at meaningfully different buildable envelopes depending on overlay boundaries, parking requirements, and how the inclusionary set-aside is structured.
Massing studies before contract, not after. Running a massing and unit mix study against a site's actual zoning envelope, before you're under contract, tells you whether a deal pencils before you've tied up capital in a purchase agreement. This matters more under the Fourth Round rules than it did under prior rounds, because so many of the newly rezoned sites are in towns with no track record of processing this kind of application, and the ordinance language is new enough that assumptions from other jurisdictions don't transfer cleanly.
Unit mix and set-aside interact. The inclusionary percentage a municipality requires changes what unit mix makes financial sense, and that in turn changes the building envelope you need. Running that math early, architecturally, before a land deal closes, catches the sites that look good on a zoning summary but don't support a viable project once the real constraints are modeled.
What a Feasibility Study Answers
A real feasibility study on a Fourth Round site should answer a short list of concrete questions before a developer negotiates a purchase price: what buildable density the site supports under the town's adopted ordinance, what unit mix satisfies both the inclusionary set-aside and the market, what site constraints (parking, setbacks, existing structures) limit the buildable envelope, and how the numbers compare against acquisition cost. Skipping that work and negotiating off the zoning summary alone is how developers end up under contract on a site that looked viable on paper and isn't once the real constraints are modeled.
The Window Is Now
Because the Fourth Round obligation runs through 2035, this isn't a narrow window that closes in a year. But the towns still finalizing implementation, and the sites just becoming available as a result, represent the earliest and often least competitive opportunities in this cycle. Developers who run feasibility studies now, while other buyers are still waiting for zoning clarity, get first look at sites before they're bid up.
PUR4 Studios runs architectural feasibility studies for New Jersey developers evaluating sites under Fourth Round rezoning, covering massing, unit mix, and buildable envelope before a purchase agreement is signed.