ADUs are allowed in AllentownTypes:DetachedInternal
Types:DetachedInternal
Accessory Dwelling Unit (ADU) Rules for Allentown, PA
Is your property eligible for an ADU?
# of Properties
29,885
Owner-occupied
66%
Zoning districts
36
Avg Home Value
$123,472
Median Lot Size
0.06 acres
Avg Income
$61,603
Residential Types:
29,885 housing units
Single Family
92%
Apts (4+ units)
2%
Condos
5%
Other
2%
Zoning Districts:
33,892 parcels · 36 districts
R-MH
40%(13,409)
R-M
27%(9,038)
R-L
13%(4,368)
R-ML
7%(2,381)
Other
14%(4,696)
ADU Rules
What can you build in Allentown, PA?
Allentown, PA 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
Interior / Attached ADU Size Limits
- –Maximum size of 800 sq ft
- –Maximum size of 40% of the floor area of the principal dwelling unit
Detached ADU Size Limits
- –Maximum detached ADU size of 800 sq ft or 40% of the principal dwelling’s floor area, whichever is less
Max Units
- –1 ADU per lot
Owner Occupancy
- –Owner must occupy either the principal or ADU as permanent residence
Parking
- –1 space/ADU
Rental Restrictions
- –Short-term rentals prohibited for both the principal unit and the ADU
ADU State Law
What can you build in Pennsylvania?
- –Pennsylvania 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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Is your property eligible for an ADU?
ADU rules in other Pennsylvania municipalities
Rules change at the town line. Check the municipality your property is actually in.
Lehigh County