ADUs are allowed in Hermitage City (Mercer)Types:DetachedInternal
Types:DetachedInternal
Accessory Dwelling Unit (ADU) Rules for Hermitage City (Mercer), PA
Is your property eligible for an ADU?
# of Parcels
7,688
Zoning districts
23
Avg Parcel Value
$39,058
Zoning Districts:
7,698 parcels · 23 districts
SR1
46%(3,552)
SR2
20%(1,539)
RR
14%(1,068)
PRD
5%(351)
Other
15%(1,188)
ADU Rules
What can you build in Hermitage City (Mercer), PA?
Hermitage City (Mercer), 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 50% of the principal dwelling’s gross floor area.
- –In SR-1 or SR-2, maximum ADU area is 1,000 sq ft on lots up to 0.5 acre and 2,000 sq ft on lots over 0.5 acre up to 1 acre; no SR cap above 1 acre.
Detached ADU Size Limits
- –Maximum size is 50% of the principal dwelling’s gross floor area; in SR-1/SR-2 it is also capped at 1,000 sq ft on lots up to 0.5 acre and 2,000 sq ft on lots over 0.5 acre up to 1 acre.
Owner Occupancy
- –Owner must reside in the property (principal or ADU) at all times.
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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ADU rules in other Pennsylvania municipalities
Rules change at the town line. Check the municipality your property is actually in.
Mercer County