Navigating the New York City Zoning Resolution

A lower Manhattan New York City Zoning Map. (Courtesy of New York City Department of Planning)

When working with a client on a new building, or an addition to an existing structure, one of the services we provide early on in the design process are zoning studies. To produce these, we consult the New York City Zoning Resolution, which regulates land use in the five boroughs. The zoning text is a robust document and addresses the uses allowed and the maximum size and shape of the building(s) on a particular lot. The rules differ depending on which zoning district the lot is located in.

To distinguish each other, zoning districts are assigned a letter (R for residential, C for commercial, M for manufacturing), followed by one or two numbers, and sometimes additionally by a letter suffix (A, B or X). The number typically indicates the density of the district, the number “1” being the least buildable. The letter suffix denotes a special district (historic or mixed use).

Uses allowed in each district are specified in the zoning resolution and aren’t as simple as you might imagine. For example, if a district is labeled residential, it does not necessarily mean it can only house residential uses. Many residential districts allow for community facilities or commercial uses. Also, not all residential buildings are allowed in certain residential districts. Districts R1 and R2 for example, only allow single-family residences.

Bulk regulations within the zoning resolution help specify many details that are crucial to the construction process, including the maximum floor area that may be built on a lot, the maximum building height, any required set-backs and the maximum square footage available to be built on. This is also crucial information for architects and contractors, as it gives us a set amount of space to work with.

An example of a New York City zoning diagram. (Courtesy of New York City Department of Planning)

Besides defining how much space we have, the zoning resolution also defines exactly how much of the lot we can develop. For example, in residential districts, some area of the lot needs to remain unbuilt to allow for sufficient light and ventilation for the living rooms and bedrooms of the residences. This requirement is referred to as “maximum lot coverage” and varies from 30 percent to 70 percent. In commercial and manufacturing districts, typically the entire lot may be covered by a building, but setbacks are required for residential uses in non-residence districts.

Another aspect of the design and construction process the zoning resolution can dictate is the shape of a building. Within the zoning resolution, terms such as the “zoning envelope” or “sky exposure plane” sound vague, but wield a lot of visual influence. For example, if you take a zoning lot, and apply all required setbacks and height limitations to fit the required zoning envelope and sky exposure plane, a certain volume will emerge, and the building must stay within this volume.

Suffice it to say, the zoning text is quite complex. Thankfully, the New York City Department of Planning implemented some helpful tools in recent years to navigate it. The Department of Planning website now contains simple descriptions and diagrams for each zoning district, an illustrated glossary of zoning terms and ZOLA — which is a map that allows the search for a property by address or block and lot number, and provides lot size, zoning district and other pertinent information.

However, to fully grasp the depth and fine print details of the text and ensure your projects abide by its rules, a professional who knows the ins and outs is always helpful. At Katz, we take pride in our specialized zoning knowledge and assisting our clients in making the most of what their particular conditions afford them. Zoning studies prepared by us are comprehensive documents that contain a written interpretation of applicable rules as well as three-dimensional diagrams to illustrate clearly what is possible given the space they have to use.