Building a Pool House in Short Hills, NJ: The Ultimate Zoning & Design Guide
Are you looking to elevate your outdoor lifestyle with a custom pool house? In Short Hills, a well-designed pool house is more than just a place to store towels—it’s a functional extension of your home that adds significant value and aesthetic appeal to your property.
However, navigating the Township of Millburn’s strict zoning ordinances is the first step toward a successful build. This guide focuses on the R-3, R-4, R-5, and R-6 zones, which represent the majority of single-family lots in Short Hills with the space to accommodate such a project. To confirm which zone your property is located, type your address into the Millburn Interactive Zoning Map.
What is a "Pool House" in Millburn Zoning?
In the Township of Millburn, a pool house is legally classified as an Accessory Use. This means the structure must be:
Subordinate to the principal single-family dwelling.
Used for private purposes only.
Designed to serve the principal use of the property.
Why Consider a Pool House?
Beyond the luxury of a private retreat, a pool house provides essential utility:
Convenience: On-site changing rooms and bathrooms keep wet feet out of the main house.
Organization: Dedicated space for pool filters, heaters, and seasonal furniture storage.
Design Continuity: New developments must be compatible with existing neighborhood patterns.
Critical Requirements for R-3, R-4, R-5, & R-6 Zones
1. Placement and Footprint
The location of your pool house is strictly regulated to preserve open space:
Rear Yard Only: All accessory uses must be constructed within rear yards (except for specific corner lot modifications).
Footprint Limit: Your pool house cannot occupy more than 20% of your rear yard area.
Open Space Preservation: The unoccupied portion of your rear yard must include an area equal to at least 25% of your total lot area.
Proximity to Main House: If the pool house is attached to or located within four feet of the principal building, it is legally considered part of the main house and must meet all stricter "bulk" requirements for principal buildings.
2. Size, Height and Coverage Limits
Maximum Size: A unique element of the Millburn zoning code is that there is no fixed limit to the size of the accessory structure - all of the requirements are based on the size of your lot and rear yard. As a result, if your lot / rear yard is large, the pool house can also be quite large. For comparison, the zoning code in Summit, NJ limits Accessory Structures to a maximum of 576 square feet (much smaller than many of the pool houses we have designed in Short Hills and Millburn).
Maximum Height: The total structure height for an accessory pool house in any of these zones is capped at 18 feet.
Building Coverage: The pool house counts toward your total building coverage: R-3 (13%), R-4 (14%), R-5 (18%), and R-6 (23%).
Total Lot Coverage: Includes the house, pool, patio, and pool house. For R-3, R-4, and R-5, the limit is 35%, while R-6 allows up to 45%.
3. Required Setbacks
"Setbacks" determine the minimum distance that the Pool House needs to be from the side / rear property lines in each zoning district.
R-3 Zone: Minimum Side Setback: 12 feet Minimum Rear Setback: 12 feet
R-4 Zone: Minimum Side Setback: 12 feet Minimum Rear Setback: 12 feet
R-5 Zone: Minimum Side Setback: 9 feet Minimum Rear Setback: 9 feet
R-6 Zone: Minimum Side Setback: 5 feet Minimum Rear Setback: 5 feet
Technical Details: Equipment & Systems
Millburn has specific rules for the "mechanicals" that make your pool house functional:
Supportive Equipment: Mechanical equipment for the pool house must have a setback equal to three times the accessory use setback, OR be within five feet of the principal house and located in the rear yard.
Air Conditioning: Units can only be in the side or rear yard. If in the side yard, they must be screened by fencing or evergreens and located twice the distance of the required side yard setback from your neighbor's house.
Emergency Generators: If you include a generator, it must meet accessory setbacks, be screened from view, and typically be located in the side or rear yard.
Important Usage Restrictions
No Short-Term Rentals: Pool houses cannot be used as independent short-term rental units.
Driveway Setbacks: In R-3 and R-4 zones, any driveway leading to the pool area must be at least 5 feet from the property line.
Commercial Vehicles: You cannot park or store commercial vehicles (capacity over 3/4 ton) on the property if they are visible from the street.
Expert Architecture for Short Hills Living
Navigating the rules govern the design of Pool Houses in Short Hills is complex. If you would like to discuss your pool house and have us analyze your property to determine what is possible, email our team at contact@johnjamesarchitecture.com