This guide provides a brief overview of the ADU zoning requirements in Princeton so you can determine whether you will be eligible to build an ADU. Keep in mind that this information is subject to change, so please be sure to check with the Princeton Planning Department for the latest rules and regulations or book a free consultation with us.
Where are ADUs allowed:
Accessory Dwellings are allowed as of right in residential zones R-A through R-H.
Types of ADUs:
In Princeton, ADUs can be constructed as detached, attached units or within the main house.
Parking:
No additional off-street parking shall be required for accessory dwelling units that contain two habitable rooms. One additional off-street parking space shall be required for accessory dwelling units that contain three habitable rooms.
Size:
The size of the accessory dwelling unit shall not exceed 800 square feet or twenty-five percent of the total floor area of the principal dwelling unit, whichever is greater. If the accessory dwelling unit is fully handicapped accessible under New Jersey’s Barrier Free sub-code, the property shall be granted an increase of five percent of the total maximum floor area allowed, which can be applied either to the principal dwelling or to the accessory dwelling, or both.
There can not be more than three bedrooms in an Accessory Dwelling Unit.
Other Requirements:
The distance between the detached accessory dwelling unit and the habitable portion of the principal single-family dwelling can not be less than five feet.
There is no minimum lot size requirement, however specific setback and lot coverage requirements of the district will apply.
At Haven, we understand that navigating zoning regulations can be challenging and time-consuming for homeowners. We created our free consultation service to make this process as simple as possible for homeowners. Book a free consultation to get started on your ADU project in Princeton, NJ!
