

ADUs are allowed in LambertvilleTypes:DetachedInternal
Types:DetachedInternal
Accessory Dwelling Unit (ADU) Rules for Lambertville, NJ
Is your property eligible for an ADU?
# of Properties
1,855
Owner-occupied
71%
Zoning districts
11
Avg Home Value
$454,685
Median Lot Size
0.06 acres
Avg Income
$125,759
Residential Types:
1,855 housing units
Condos
4%
Other
96%
Zoning Districts:
2,139 parcels · 11 districts
R-2
49%(1,053)
R-1
18%(392)
CBD
12%(264)
R-L
9%(192)
Other
11%(238)
ADU Rules
What can you build in Lambertville, NJ?
Lambertville, NJ follows state and local rules for Accessory Dwelling Units. Here is a concise overview of the local rules.
Eligibility
- –Internal / Attached ADU: Conditional Use Permit
- –Detached ADU: Conditional Use Permit
Interior / Attached ADU Size Limits
- –Maximum accessory apartment size of 900 sq ft.
- –In the Central Business District: basement/cellar apartments are prohibited; first-floor accessory apartments are limited to 50% of the first-floor area.
Detached ADU Size Limits
- –Maximum size of 900 sq ft for a detached accessory dwelling (includes ECHO units and accessory apartments in accessory structures).
Max Units
- –Accessory apartment: 1 per lot
Owner Occupancy
- –Occupants must be family members of the owner/occupant of the primary dwelling.
Parking
- –No separate numeric ADU minimum; citywide RSIS applies. Maximum parking not specified. Off-tract parking within 300 ft with guaranty; EVSE/make-ready counts as two spaces toward the minimum (10% overall reduction cap).
Rental Restrictions
- –ADUs must be rented to low- or moderate-income households; rents capped; affirmatively marketed and deed-restricted affordable for a minimum of 10 years.
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.
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ADU rules in other New Jersey municipalities
Rules change at the town line. Check the municipality your property is actually in.
Hunterdon County
Alexandria TownshipBethlehem TownshipBloomsbury BoroughCalifon BoroughClintonDelaware TownshipEast Amwell TownshipFlemington BoroughFranklin Township (Hunterdon)Frenchtown BoroughGlen Gardner BoroughHampton BoroughHigh Bridge BoroughHolland TownshipKingwood TownshipLebanon BoroughMilford BoroughReadington TownshipTewksbury TownshipUnion Township (Hunterdon)West Amwell Township