R10 Zoning NYC
R10 Zoning is a residential zoning district in NYC that allows for the highest buildable floor areas of all residential zoning. In R10 zoning you have an optional zoning bonus for providing 20% affordable units. There are several building typologies that can be developed in R10 Zoning.
This post is going to focus on regular R10 Zoning and not with R10 contextual Zoning.
R10 Zoning Districts
Regular R10 District:
R10 Contextual Districts
Commercial Zoning With Residential Equivalent R10 Zoning
Most Commercial Zoning districts allow for residential use. Below are Commercial zones with R10 Residential Equivalents.
What is R10 Zoning?
R10 Zoning is considered “high density” residential zoning. R10 is the largest Residential Zoning District with the highest floor area ratios. It typically has large multifamily buildings including high rise residential towers. In an R10 zone you have 3 options for zoning regulations you can use Quality Housing Program, Tower, or Tower On A Base.
All R10 Zoning Districts have an optional Inclusionary Housing Zoning.
QUALITY HOUSING PROGRAM FOR R10 ZONES
The Quality Housing Program promotes shorter wider buildings that are typically larger in square footage. The Quality Housing Program is not to be confused with the Inclusionary Housing Program for affordable housing. The quality housing program is just another set of optional zoning regulations and has nothing to do with low income or affordable housing. Typically QHP will result in a larger building of a higher quality. There are more zoning floor area deductions in quality housing that would give you a boost to your total building size.
Quality housing is optional in R10 but Mandatory in Contextual Zoning: R10A Zoning and R10X Zoning.
R10 Tower Zoning
Standard Tower Zoning is only allowed on narrow streets (Streets under 75 feet wide). If you are on a wide street (75 wide or more) you must go with Quality housing or Tower on a Base. Tower zoning results in high rise buildings as they are allowed to penetrate the sky exposure plane which limits building height.
R10 Tower on a Base Zoning
Tower on a Base Zoning is a tower that sits on a wider base. The base follows the quality housing program regulations. And the tower follows tower regulations.
R10 ZONING COMMUNITY FACILITY
R10 Zoning is a residential zone but Community Facility uses are allowed in all R10 zones. In the instance of a community facility the zoning calculations would be different. One can also build a mixed use building with both community facility and residential use.
R9 ZONING COMMERCIAL OVERLAY
Sometimes residential districts have commercial overlays. This means the zone is primarily residential but commercial use is allowed instead or you can have both as a mixed use building. If you are building in a commercial zone with a residential equivalent you can also build mixed use buildings.
R10 INCLUSIONARY HOUSING PROGRAM
Always check if your property is subject to requirements of the Inclusionary Housing Program. These are districts that have either optional and sometimes mandatory requirements for low income housing. Typically in these areas you provide 20% of your floor area for affordable units and you get a 20% increase to the allowable floor area of the building. There can be zoning penalties if you choose not to provide it. And zoning bonuses if you do. In R10 you always have the option to do Inclusionary Housing.
R10 ZONING REGULATIONS FOR QUALITY HOUSING
Minimum Lot width =18 Feet
Minimum Lot Area = 1,700 Sq Ft
Corner Lot = 100%
Interior or Through Lot = 70%
Floor Area Ratio (FAR):
FAR = 10
FAR With Inclusionary Housing = 12
680 – This is used to calculate how many apartments you can have. The total residential floor area is divided by this factor to get the maximum allowable number of dwelling units.
Building Base Height: This indicates a setback is required at these heights
Narrow street = 60 Minimum / 125 Maximum
Wide street = 125 Minimum / 155 Maximum
Inclusionary Housing Base Height:
Narrow street = 60 Minimum / 155 Maximum
Wide street = 125 Minimum / 155 Maximum
Overall Building Height: This is the actual building height
Narrow street = 185
Wide street = 200 (215 with qualifying ground floor)
Inclusionary Housing Building Height:
Narrow street = 210 (215 with qualifying ground floor)
Wide street = 230 (235 with qualifying ground floor)
R10 Zones are subject to “Sliver Law” zoning restrictions for properties less than 45 feet wide. The sliver law is an additional restriction on the height of the building and supersedes the typical building height requirements. Sliver law is not applicable in certain special zoning districts.
Corner Lot: No Yards Required
Interior Lot = 30 foot minimum rear yard required
R10 Zoning Example for Quality Housing
Here is an example zoning analysis. Be aware that zoning is complicated and I am only addressing the basics here. I assure you there are many additional issues and variations to consider beyond this example.
R10 Zoning Example Lot
Lets assume we have a 50 foot wide and 100 foot deep property in an R10 Zoning District in Manhattan on an interior lot and lets say it is on a wide street.
R10 Quality Housing Program Example:
Building Foot Print:
First Lets start with Lot Coverage and Yards. We know we will need a minimum rear yard of 30 feet. That tells us we have 50 x 70 to build on, and we can cover 70% of the property. This works out well with a 3,500 sq ft area we can build on.
Zoning Floor Area/ Floor Area Ratio (FAR)
So the floor area ratio is 10. The FAR is a ratio that determines how many square feet you can build on the property. You simply take the property size and multiply it by the FAR.
In this example we have:
FAR of 10 (it would be 12 with Inclusionary Housing)
Lot Size of 50 feet x 100 feet.
Zoning Floor Area = Lot Area X FAR
Lot Area = 50 x 100
Lot Area = 5,000 sq ft
FAR = 10
Zoning Floor Area = 5,000 sq ft x 10
Zoning Floor Area = 50,000 sq ft
So we can build a 50,000 sq ft building. This is the zoning square footage the actual building will be a little bigger than that when you figure out zoning deductions.
We said our building foot print would be 50 x 70. Or 3,500 per floor.
This will give us a 14 or 15 story building. If we provide a setback the building will be 15 stories.
How Many Apartments Can We Develop on our R10 Lot?
Zoning regulates the maximum number of residential units you can put in a building. In this apartment building we have 50,000 zoning square feet. We then take the zoning Area and divide by the Density factor.
Number Of Apartments = Zoning Floor Area ÷ Density Factor
Number Of apartments = 50,000 ÷ 680
Number Of Apartments = 73.52 we must round down in this case
Maximum Number Of apartments = 73
R10 ZONING EXAMPLE CONCLUSION
In this example we are proposing to build a 50,000 sq ft building. The apartment building will be 15 stories tall and have a setback at least on the top couple floors. The Building will have a foot print of 50 x 70. It will have a maximum of 73 apartments but can have less as well.
As an architect I study zoning very closely. NYC Zoning is complicated and quite involved. In this article we reviewed some of the basic Zoning Codes with regards to residential zoning district R10. This analysis does not assume to cover every possible issue and condition, but provide a general overview. This post does not substitute the NYC Zoning Resolution.
Thank You for Reading Our Blog Post on R10 Zoning.
I hope this was helpful. You can leave questions or comments below. If you want to discuss a specific project with an architect please feel free to contact us directly. We will be happy to help.
Author Jorge Fontan AIA
This post was written by Jorge Fontan, a Registered Architect and owner of Fontan Architecture.