Mixed Use Building Design NYC FAR

by | Last updated May 7, 2022 | NYC Zoning, Property Development

According to New York Zoning code a mixed use building is a building with residential use and another use for example a residential building with commercial space on the first floor.

As an architect I get a lot of clients who are confused about how to determine the buildable floor area according to NYC Zoning for mixed use building design. In this post we are going to look at how the zoning floor area works for mixed use building design.


Mixed Use Building Design

First things first. What is a mixed use building?

A mixed use building is a building with more than one use combing two or more of the following: residential, commercial, community facility, and ore manufacturing uses. When 2 or more of these are combined in one building you have a mixed use building.

NYC Zoning Uses:

There are 4 basic uses for buildings in NYC:

  • Residential
    • Residential zoning districts begin with an R
  • Commercial
    • Commercial Zoning Districts begin with a C
  • Manufacturing 
    • Manufacturing districts begin with an M
  • Community Facility
    • There are no Community Facility zoning districts in NYC most zoning districts will allow for Community Facility use.


Mixed Use Developments

There are many different zoning conditions that would allow for a mixed use development. Here are a few examples where you might be able to put 2 different uses in one building.

Residential Zoning with Community Facility

In NYC all Residential Zoning Districts will allow for Community Facility uses. Examples of a community Facility would be religious buildings, community centers, hospitals, schools, etc… It is allowed to make one mixed use building with both residential and community facility use.

Residential Zoning with Commercial Overlay

Commercial is only allowed in residential zones if they are Residential with Commercial Overlay zones. A common example, in this case, would be a commercial space on the ground floor with apartments above.

Commercial Zoning With Residential Equivalent

Most commercial zones have residential equivalent zones. A residential equivalent in commercial zoning means you have the option of doing residential in the commercial zone. There will be a residential zone assigned as the equivalent to the commercial district. In this case you can make a mixed use building. An example would be a building with offices and residential in one building. another example would be hotel and residential in one building. Hotels are commercial zoning not residential.

Commercial Zoning with Community Facility

In NYC most commercial districts will allow for Community Facility uses. It is allowed to make one mixed use building with both commercial and community facility use.

Manufacturing Paired Districts

Some manufacturing districts have what is called a paired district. the paired district is a residential district where both regulations apply residential and manufacturing. these districts allow for mixed use buildings to promote residences in manufacturing districts. you can see examples of this in Long Island City where there is a great deal of residential use in manufacturing zoned areas.

Commercial Use in Manufacturing Districts

Most manufacturing districts will allow commercial use. You could if you wanted build a manufacturing building with some commercial use in it.


In Mixed Use Buildings With Commercial Use

Section 32-422 of the zoning code prohibits commercial use above residential or community facility use. Or on the same floor except on the ground floor.


Mixed Use Building Design Floor Area Ratio = FAR

Floor Area Ratio (FAR) is a proportion that determines how many square feet your building can be. You multiply the lot square footage by the Floor Area Ratio and that gives you the total square footage allowed for the building development. For example if a 10,000 sq foot lot has an FAR of 2 you can build a 20,000 square foot building on the property.

Floor Area Ratio for different Uses

It will often be the case when a property has more then one use that each use has a different floor area ratio. When this is the case you do not add the different FARs together. This is a common misconception I hear from a lot of people. The total building square footage will be governed by the largest of all available FARs. The other FARs available will dictate the extent of each individual use.


FAR Calculation Examples:

If I have a Property in a C6-6 Zoning district I could build a commercial and residential mixed use building.

The Commercial FAR is 15

The Residential Equivalent is R10 with an Residential FAR of 10

Learn more about Floor Area Ratio in another post we wrote.

Lets assume for this example the property is 100 feet by 100 feet with a total lot area of 10,000 sq feet.

In this case we could have several options.

Single Use Building Options

Commercial Option

We could build a completely commercial building.

Lot Area X Commercial FAR = Buildable Square Footage

10,000 x 15 = 150,000 square feet

You could build a 150,000 square foot commercial building.

Residential Option

what if you only wanted to build a residential building.

Lot Area X Residential FAR = Buildable Area

10,000 x 10 = 100,000 square feet

In this option you could build a 100,000 square foot residential building. FYI in this option you could have a bonus for Inclusionary Housing but I’m not getting into that here. I’m trying to keep to the point of FAR calculations for mixed use buildings.

Our first 2 example where not actually mixed use buildings I just used those to illustrate simple FAR calculations. how do we calculate FAR for a mixed use building.

Mixed Use Building Options

Lets say we want to build mixed use building. If our maximum residential FAR is 10 and our Maximum Commercial FAR is 15 then a mixed use building can have a maximum FAR of 15 and the residential portion of the building cannot exceed an FAR of 10.

Mixed Use Maximizing Residential FAR

Maximum Building FAR = 15

10,000 x 15 = 150,000 square feet

You could build a 150,000 square foot commercial building.

Residential FAR = 10

10,000 x 10 = 100,000 square feet

Commercial FAR remaining = 5

10,000 x 5 = 50,000 square feet

In this option we could build a mixed use building with a maximum floor area of 150,000 square feet. Of this square footage we could build 100,000 square feet of residential space and 50,000 square feet of commercial. Of course you can increase you commercial space as long as you decrease the residential space. the total cannot exceed 150,000 square feet in this situation.


Mixed Use Building Zoning

As an architect, I study Building Codes and Zoning Codes closely, but these are complicated and quite involved issues. In this article, we reviewed some of the basic concepts with regards to Zoning for Mixed Use Buildings District. This post does not assume to cover every possible issue or condition, but provide a general overview of the topic.


Thank You for reading our blog post on Mixed Use Building Design Design

I hope this was helpful. Please feel free to leave a question or comment bellow. If you want to discuss a specific project and are looking to talk with an architect you can contact us directly.


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Jorge Fontan

Jorge Fontan

This post was written by Jorge Fontan AIA a Registered Architect and owner of New York City architecture firm Fontan Architecture. Jorge Fontan has earned 3 degrees in the study of architecture including two degrees from the City University of New York and a Masters Degree in Advanced Architectural Design from Columbia University. Jorge has a background in construction and has been practicing architecture for 20 years where he has designed renovations and new developments of various building types.