What Is a Zoning Lot Merger?

A zoning lot merger is a legal mechanism in NYC that combines two or more adjacent tax lots into a single "zoning lot" for the purpose of calculating development rights. This allows unused Floor Area Ratio (FAR) from one lot to be used on another lot within the merged zoning lot.

How Zoning Lot Mergers Work

When two adjacent lots merge into a single zoning lot, the total allowed floor area is calculated across the combined lot area. If one lot has an underbuilt building (using less than its allowed FAR), the unused FAR can be shifted to the other lot within the merged zoning lot, allowing a larger building there.

Requirements

• Adjacency - The lots must be adjacent (sharing a common lot line or separated only by a street)
• Same Zoning District - The lots should be in the same or compatible zoning districts
• Declaration - A Zoning Lot Development Agreement (ZLDA) or Declaration of Restrictions is recorded with the City Register
• Ownership - The lots do not need to be under the same ownership; agreements between separate owners are common

Air Rights Transfers

Zoning lot mergers are the primary mechanism for "air rights transfers" in NYC. When a landmark building or low-rise structure sells its unused FAR to an adjacent developer, this is accomplished through a zoning lot merger. These transactions can be worth millions of dollars in high-density districts.

Common Scenarios

A frequent scenario involves a landmark building (like a church or historic structure) that cannot be demolished or significantly enlarged. The unused development rights above the landmark can be sold to an adjacent lot through a merger, allowing the adjacent property to build higher than the base zoning would allow.