NYC Zoning Basic Introduction
New York City Zoning is very complicated and confusing. The NYC Zoning Resolution is thousands of pages long and constantly being updated. There are many different zoning districts, terms, and formulas, you would need to understand to have a working knowledge of NYC Zoning.
On our Architecture Blog we write posts on many different topics including Zoning. As an architect I find zoning is the most complicated issue my clients are trying to understand. Below are some general concepts in NYC Zoning and links to blog posts that explain all these in more detail.
As I said Zoning is complicated. This website is meant to be a simplified explanation of these issues and does not substitute the Zoning Resolution. These are my interpretations of complicated issues in an attempt to make them easier to understand.
The Following are the New York City Zoning Districts as well as terms that would typically be used when dealing with zoning.
NYC Zoning Districts
New York City is broken up into Zoning Districts each district regulating what you can build.
Types of NYC Zoning Districts:
- Commercial Zoning
- Manufacturing Zoning
- Residential Zoning
Additional Zoning District Issues
- Commercial Overlay
- Community Facility Zoning
- Contextual Zoning
- Inclusionary Housing Program
- Quality Housing Program
- Residential Equivalent
- Special Purpose Zoning Districts
NYC Zoning Definitions
Below are some basic terms used in NYC Zoning. Article 1 chapter 2 AKA Chapter 12 of the NYC Zoning Resolution has all the NYC Zoning Definitions. Below we will give you some of the most commonly used terms and links to articles we wrote with interpretations or examples.
- Building Types
- Attached, Semi-Detached, detached, and Zero Lot Line
- Density Factor or Dwelling Unit Factor (DU)
- Development Rights
- Air Rights Transfer or Zoning Lot Merger
- Building Enlargement
- Floor Area Ratio (FAR)
- Floor Area Deductions
- Height Factor Zoning
- Home Occupation Zoning Restrictions
- Infill Housing
- Predominantly Built Up Area
- Minimum Apartment Size
- Mixed Use Buildings
- Narrow Lots
- Shallow Lots
- Sky Exposure Plane
- Sliver Law
- Small Zoning Lots
- Street Width
- Wide Street vs Narrow Street
Additional NYC Zoning Information
We have some additional posts that deal with zoning related issues. See explanations below.
- Dividing Lots
- Hotel Zoning
- Zoning Analysis
NYC Zoning Districts
Zoning Districts beginning with the Letter C are Commercial Zoning Districts. For Example C5-2 and C6-9 are Commercial Zoning Districts. See another post we wrote for a complete list of Commercial Zoning Districts in NYC.
Zoning Districts beginning with the Letter M are Manufacturing Zoning Districts. For Example M1-1 and C2-4 are Manufacturing Zoning Districts. See another post we wrote for a complete list of Manufacturing Zoning Districts in NYC.
Zoning Districts beginning with the Letter R are Residential Zoning Districts. For Example R2, R4-1, and R7A are Residential Zoning Districts. See another post we wrote for a complete list of Residential Zoning Districts in NYC.
Additional Zoning District Information
A commercial Overlay is a Commercial area mapped within a Residential Zoning District. In these areas you can build a residential building, a commercial building, or a mixed use building. Learn more about Commercial Overlay Zoning.
Community Facilities are allowed in most zoning districts in NYC. In many cases they will have different zoning regulations than the basic zoning district. We have another post you can look into to learn more Community facility Zoning NYC.
Contextual Zoning districts are areas where the city is looking to maintain a certain character of the neighborhood. All zoning districts that end with a letter are contextual zoning. For example R8B or R6A. In R6 – R10 districts you must develop buildings as per the Quality Housing Program in Contextual Zoning.
Inclusionary Housing Program
New York City is looking to encourage developers to build mixed income buildings and affordable housing units. The Inclusionary Housing Program is a zoning regulation optional in some areas and mandatory in others that give zoning benefits for developing affordable residential units. Check out another blog post we wrote on Inclusionary Housing.
Quality Housing Program QHP
The Quality Housing Program is set of Zoning Regulations mandatory in Contextual Zones R6 – R10 and optional in Non-contextual zones R6 – R10. Quality housing program differs from height factor zoning in one major way. Height Factor Zoning creates tall skinny buildings, and Quality Housing results in shorter wider buildings. Learn More about Quality Housing.
You can develop residential buildings in most Commercial Zoning Districts. The commercial districts have a Residential Equivalent. This is a residential zone that is matched with he Commercial Zone. In this case you generally follow the Residential Equivalent Zoning Regulations. See a list we made of commercial and residential zoning equivalents.
Special Purpose Districts
New York City is filled with Special Purpose Districts. In these districts there are special regulations beyond the normal underlying zoning district regulations. See a full list of NYC Special Zoning Districts.
NYC Zoning Definitions
Attached, Semi-Detached, Detached, and Zero Lot Line
The zoning code identifies four building types:
- Zero Lot Line
It is important to understand the difference between the building types because it affects the applicability of different zoning codes on their development. See a more detailed explanation on the difference between Attached, Semi-Detached, Detached, and Zero Lot Line buildings.
Density Factor or Dwelling Unit Factor
Density Factor is a formula that determines how many dwelling units you can develop on a given property. The formula is:
Zoning Floor Area ÷ Dwelling Unit Factor = Total Allowed Number of Units
Read another post we have to learn more about Density Factor and see specifications on different residential zones.
Development Rights and Air Rights
The term air rights is not defined in the Zoning Code. Air rights is a general term for Development Rights and people often use it to mean different things. Development Rights are the extent of ones legal right to build on a property. These rights can be transferred in certain cases to another property. This is often referred to as an air rights transfer. There are 2 ways to sell or buy air rights one is a zoning lot merger and the second less common way is a development rights transfer. We have another post you can read if you want to learn how to calculate air rights.
Enlargements of Existing Buildings
An enlargement is an alteration to a building that adds floor area. If your alteration requires a new Certificate Of Occupancy then you must file an Alt 1 with NYC DOB. In some cases building additions will require the entire building to comply with New Building Codes. This is commonly referred to as a Big Alt. Read more about Building Additions and available development rights.
Floor Area Ratio
FAR or Floor Area Ratio is a formula to determine the Zoning Floor Area of a building. The Zoning Floor is calculated with the following formula:
Floor Area Ratio x Lot Area = Zoning Floor Area
If you want to sound like you know what you are talking about then you should pronounce FAR correctly. It is an initialism not an acronym. You do not pronounce the word far. You pronounce the initials F A R. Read more about Floor Area Ratio.
Zoning Floor Area Deductions
The Zoning Floor area is the total floor area of the building minus any deductions or areas not counted for zoning. There are certain areas not counted and that can be considered a zoning deduction. Although the term zoning deduction does not appear in the zoning code. Learn more about areas not counted for zoning and Zoning Deductions.
Height Factor is an optional zoning law for building height, floor area, and open space requirements in R6, R7, R8, & R9 Zoning. Height Factor is based on the Tower In The Park Architectural Philosophy of Mid Twentieth Century Modernism. Check out another post we wrote to see a detailed explanation of Height Factor Zoning.
Home Occupation Zoning
If you want to run a home based business there are several zoning restrictions you need to know about. the biggest one is that you cannot have a home office over 500 square feet or 25% of the residence floor area, whichever is less. In another post we have the full list of Home Business Zoning Laws in NYC.
Infill Housing AKA Predominantly Built Up Area
R4 Zoning and R5 Zoning both have alternate zoning regulations for Infill Housing. A Predominantly Built Up Area is a block that is entirely within an R4 or R5 zone that is mostly built up with commercial, multifamily, or attached buildings. See more details on Predominantly Built Up Areas in our R4 Infill Housing & R5 Infill Housing blog posts.
A mezzanine is a floor that occupies less than 33% of the floor below. In NYC Zoning this Mezzanine Floor does not count as a story by definition. This can in many instances provide a zoning benefit. You can read another post we wrote on building a mezzanine to learn more.
Minimum Apartment Size
For the most part Minimum Apartment Sizes have been removed from the zoning code in general. There are still certain instances that have minimum apartment sizes. Since most of these regulations have been removed people in New York have been very interested in Micro Apartments. There are still many issues to deal with on micro apartments but they are allowed in NYC but there are still requirements and restrictions. Check out another post we wrote if you want to read more about Micro Apartments.
Mixed Use Buildings
The NYC Zoning Resolution defines a Mixed Use Building as a building with residential use and another use. We have another post explaining how to do Mixed Use Building Zoning Calculations.
Sometimes properties are required to have side yards. In the case of narrow lots these yards can sometimes be reduced.
A setback is a zoning requirement for allowing light and air into streets. These are portions of buildings that are recessed from lower portions of buildings. In many parts of the country the term setback is used to define a building needing to be setback from the street. In NYC zoning that is called a yard requirement. NYC Zoning only refers to portions of buildings being recessed above a certain height as a setback. See another article we wrote to learn more about NYC Building Setbacks.
Most properties are required to have rear yards or rear yard equivalents. In the case of shallow lots these yards can sometimes be reduced or completely omitted.
Sky Exposure Plane
A sky exposure plane is an imaginary plane that sets an inclined boundary that a building cannot penetrate. The sky exposure plane establishes a limit for a building envelope as specified in the zoning code.
A sliver building is a tall building under 45 feet wide. NYC zoning has restrictions on these types of buildings that limit their height and in many cases prohibit you from maximizing the floor area of the lot. These restrictions are commonly referred to as the Sliver Law. The term Sliver Law does not appear in the Zoning Resolution it is an industry term we architects use to describe this set of Zoning Laws. Sliver Law can be a major problem for a lot of property developments in NYC. Check out another article we wrote to learn more about Sliver Law and Sliver Buildings in NYC.
Small Zoning Lots
In NYC Zoning Small Zoning Lots are Residential Zoning Lots under a particular width or size. Small Zoning Lots do not allow more than 1 or 2 family homes to be built on them. There are ways that you may be able to do multifamly on small lots. Read more about building on small lots and minimum lot size.
In Zoning Street Width can affect the regulations that apply to your property in many different ways. The zoning Resolution defines a Wide Street as being greater than or equal to 75 feet. A Narrow Street is under 75 feet wide. To read more or see illustrative diagrams see another post we wrote on Street Width in NYC.
A Zoning Variance is an action for granting special approvals to a development that is not “As Of Right”. As of Right means any development that 100% complies with Zoning Codes and does not need any special permits or approvals. The Board of Standards and Appeals handles Zoning Variances. See another post we wrote about the requirements for a Zoning Variance.
Additional NYC Zoning Information
When dividing lots into 2 or more zoning lots there are several issues to consider that may affect if you can proceed. Residential Zoning districts have minimum lot sizes that will restrict how many lots you can subdivide out of your original zoning lot. We have another post if you want to learn more about lot subdivisions.
Hotels can be developed in Commercial Zoning Districts and some Manufacturing Zoning Districts. In certain you can also build a hotel in some Residential Zoning Districts with a commercial Overlay. We have another post if you want to read more about Hotel Zoning.
A Zoning Analysis is a comprehensive report with zoning diagrams that illustrate the Zoning Development Potential of the property. At our Architecture Firm we do Zoning Analysis all the time before developing properties.
Thank You for reading our post on NYC Zoning Info.
If you have questions or comments please feel free to leave them below. If you would like to speak with an architect about a specific project you can contact us directly. We are happy to hear about your upcoming projects.
Author Jorge Fontan AIA
This post was written by Jorge Fontan, a Registered Architect and owner of Fontan Architecture.