ADUs are allowed in PrincetonTypes:DetachedInternal
Types:DetachedInternal
Accessory Dwelling Unit (ADU) Rules for Princeton, NJ
Is your property eligible for an ADU?
# of Properties
7,748
Owner-occupied
79%
Zoning districts
63
Avg Home Value
$825,804
Median Lot Size
0.34 acres
Avg Income
$203,304
Residential Types:
7,748 housing units
2-3 Family
92%
Other
8%
Zoning Districts:
8,823 parcels · 63 districts
R-5-T
14%(1,227)
R-4-B
9%(803)
R-3-B
8%(700)
R-2-T
8%(690)
Other
61%(5,403)
ADU Rules
What can you build in Princeton, NJ?
Princeton, NJ follows state and local rules for Accessory Dwelling Units. Here is a concise overview of the local rules.
Eligibility
- –Internal / Attached ADU: By Right
- –Detached ADU: By Right
Max Units
- –1 per one-family lot (if permitted)
- –R4: 0 for two-family/attached/multifamily lots
Parking
- –No min/max; exceptions: driveways not in the front yard may count toward parking; parking cannot be in a required front yard and must be 4 ft from lot lines; may be on the same lot or within 400 ft with deed restrictions.
ADU State Law
What can you build in New Jersey?
- –New Jersey does not have a statewide ADU mandate; ADU rules are set by individual municipalities.
- –Building/fire codes are set statewide, but whether an ADU is allowed is local zoning.
What's allowed on your lot?
These are the municipality-wide rules. What's allowed on a specific property also depends on state laws, setbacks, floor area ratio, lot coverage, environmental constraints, topography, and other property-specific factors. Search your address on FutureLot to see what's allowed on your property.
Check my propertyHow can we help you?
Get matched with trusted local builders
Understand what's allowed on your property
Learn the key rules and size limits for ADUs
Is your property eligible for an ADU?
ADU rules in other New Jersey municipalities
Rules change at the town line. Check the municipality your property is actually in.
Mercer County