Accessory Structures in Pennsylvania (2026)
52 rules on the books across Pennsylvania, 20 cities and counties. Select a rule to read the full details.
Severity: Few Restrictions · Light Restrictions · Some Restrictions · Significant Restrictions · Heavy Restrictions
ADU Rules
Rules for building accessory dwelling units (granny flats, in-law suites) including size limits, parking requirements, and owner-occupancy rules.
Philadelphia
Heavy RestrictionsPhiladelphia permits accessory dwelling units (ADUs) only on lots in the RSA-5 or CMX-1 base zoning districts (and…
Read full rule →Bristol Township
Significant RestrictionsBristol Township calls an accessory dwelling an accessory apartment: a separate dwelling unit subordinate in size to a…
Read full rule →Lower Merion
Significant RestrictionsLower Merion Township permits a restricted accessory dwelling unit in LDR, MDR, IC, and IH Zoning Districts by…
Read full rule →Millcreek
Significant RestrictionsIn Millcreek Township, Erie County, Pennsylvania, the only accessory dwelling the code allows is an In-Law Apartment…
Read full rule →Pittsburgh
Significant RestrictionsPittsburgh caps accessory dwelling units at 800 square feet and allows only one per lot inside the mapped ADU Overlay…
Read full rule →Reading
Significant RestrictionsReading zoning caps most residential lots at one dwelling unit and bars converting a garage or other accessory building…
Read full rule →Upper Darby
Significant RestrictionsUpper Darby allows accessory dwelling units only by special exception in single-family detached or semidetached homes…
Read full rule →Allentown
Some RestrictionsAllentown expressly allows accessory dwelling units (ADUs) on lots occupied by a single dwelling unit. An ADU may not…
Read full rule →Delaware County
Some RestrictionsDelaware County does not regulate accessory dwelling units. Under Pennsylvania's Municipalities Planning Code, zoning…
Read full rule →Erie
Some RestrictionsErie added accessory dwelling units to its zoning code by Ordinance No. 52-2024 (passed 9-18-2024), defining an ADU as…
Read full rule →Franklin Township
Some RestrictionsFranklin Township, Chester County, Pennsylvania scales how many additional dwelling units a property may add to its lot…
Read full rule →Harrisburg
Some RestrictionsIn the City of Harrisburg, Pennsylvania, an accessory dwelling unit is allowed by right in the RL, RM, and RF Zoning…
Read full rule →Lower Paxton
Some RestrictionsIn Lower Paxton Township, Dauphin County, Pennsylvania, an accessory dwelling unit is a separate living space attached…
Read full rule →Montgomery County
Some RestrictionsMontgomery County does no land-use zoning. Whether an accessory dwelling unit is allowed, and its size and setbacks, is…
Read full rule →Scranton
Some RestrictionsScranton's zoning code defines and permits accessory dwelling units under Section 445-8, allowing a second residential…
Read full rule →ADU Owner Occupancy
Whether the property owner must live on-site to operate an ADU, deed-restriction requirements, and recent state-law changes lifting owner-occupancy rules.
Franklin Township
Significant RestrictionsFranklin Township, Chester County, Pennsylvania only allows an additional dwelling unit on a residential property where…
Read full rule →Lower Merion
Significant RestrictionsWhen a Lower Merion Township restricted accessory dwelling unit is not owner-occupied, § 155-10.2.C(10) requires its…
Read full rule →Millcreek
Significant RestrictionsIn Millcreek Township, Erie County, Pennsylvania, an In-Law Apartment is allowed only in a Dwelling that is…
Read full rule →Philadelphia
Some RestrictionsAn accessory dwelling unit or the main house must stay owner-occupied, locked in by a recorded deed restriction before…
Read full rule →Pittsburgh
Some RestrictionsPittsburgh's Accessory Dwelling Unit Overlay District requires the property owner to live on-site whenever an ADU is…
Read full rule →ADU Rental Restrictions
Whether an ADU can be rented short-term (Airbnb), 30-day minimums, separate rental licenses, and long-term lease requirements.
Allentown
Heavy RestrictionsUnder Allentown's zoning code, any lot with an accessory dwelling unit loses the right to rent either unit short-term…
Read full rule →Franklin Township
Heavy RestrictionsFranklin Township, Chester County, Pennsylvania bars any additional dwelling unit from being used as a short-term…
Read full rule →Millcreek
Heavy RestrictionsMillcreek Township Code § 145-58(H) in Erie County, Pennsylvania expressly prohibits occupancy or rental of an In-Law…
Read full rule →Upper Darby
Heavy RestrictionsUpper Darby bars renting an accessory dwelling unit on the open market: § 550-17B(2) limits occupancy to people related…
Read full rule →Pittsburgh
Significant RestrictionsAccessory Dwelling Units built under Pittsburgh's ADU Overlay District can't be leased for stays shorter than 30 days…
Read full rule →Shed & Carport Rules
When a storage shed or carport needs a permit, the square-footage exemption thresholds, and the setback and height limits that apply either way.
Allentown
Some RestrictionsIn Allentown a storage shed is an accessory structure that generally may not exceed 15 feet in height, may not stand in…
Read full rule →Bensalem
Some RestrictionsBensalem Township lets homeowners build a private garage or other accessory building, including a shed, only if it…
Read full rule →Bristol
Some RestrictionsIn Bristol Borough, Pennsylvania, a freestanding residential accessory structure such as a garage, greenhouse…
Read full rule →Bristol Township
Some RestrictionsIn Bristol Township, Pennsylvania, a storage shed, bathhouse or private greenhouse must stand in the required side…
Read full rule →Erie
Some RestrictionsIn Erie's 'R' districts a detached accessory building (shed) must sit in the side or rear yard, at least 6 ft from any…
Read full rule →Franklin Township
Some RestrictionsSheds and other accessory structures in Franklin Township's Agricultural-Residential District cannot sit in the front…
Read full rule →Harrisburg
Some RestrictionsIn the City of Harrisburg, Pennsylvania, a storage shed is a residential accessory structure that must meet the setback…
Read full rule →Haverford
Some RestrictionsIn Haverford Township, Delaware County, accessory buildings other than garages are limited to one story or 12 feet in…
Read full rule →Lower Merion
Some RestrictionsLower Merion Township limits every accessory building and structure, sheds included, to two stories or 20 feet if it…
Read full rule →Lower Paxton
Some RestrictionsIn Lower Paxton Township, Dauphin County, Pennsylvania, a residential shed must sit at least 7.5 feet from every…
Read full rule →Millcreek
Some RestrictionsIn Millcreek Township, Erie County, Pennsylvania, every accessory structure needs a permit except a one-story detached…
Read full rule →Montgomery County
Some RestrictionsMontgomery County sets no shed rule. Whether a shed needs a zoning or building permit, and how far it must sit from lot…
Read full rule →Philadelphia
Some RestrictionsPhiladelphia exempts a small shed from permits only when it is 120 sq. ft. or less, no taller than 15 ft. (one story)…
Read full rule →Pittsburgh
Some RestrictionsCarports are permitted by-right as residential accessory structures in Pittsburgh, but must meet the same front and…
Read full rule →Pottstown
Some RestrictionsPottstown's zoning code caps a residential storage shed at 120 square feet and eight feet in height, and requires every…
Read full rule →Reading
Some RestrictionsReading allows a private garage or carport in the rear setback if the vehicle door sits at least three feet from an…
Read full rule →Scranton
Some RestrictionsScranton's Zoning Ordinance defines a storage shed as an "accessory structure" and regulates it at § 445-28: it must…
Read full rule →Upper Darby
Some RestrictionsUpper Darby caps accessory buildings, including sheds, at 15 feet in height and bars them from required front yards or…
Read full rule →Monroe County
Few RestrictionsA shed under 1,000 square feet accessory to a one-family home is exempt from the state building permit in Monroe…
Read full rule →Garage Conversions
Rules for converting a garage into living space, including whether you need to replace the lost parking and what building codes apply.
Lower Paxton
Significant RestrictionsIn Lower Paxton Township, Dauphin County, Pennsylvania, no part of an accessory garage can be occupied as a residential…
Read full rule →Allentown
Some RestrictionsAllentown allows a detached garage or other outbuilding to be converted to living space as an accessory dwelling unit…
Read full rule →Erie
Some RestrictionsErie defines a private garage as an accessory building used only to store the occupants' vehicles and personal effects…
Read full rule →Lower Merion
Some RestrictionsLower Merion Township's zoning code lets a converted garage revert back into a garage as of right, but freezes it at…
Read full rule →Monroe County
Some RestrictionsTurning a garage into living space in Monroe County is a change of occupancy. Under the Uniform Construction Code you…
Read full rule →Montgomery County
Some RestrictionsMontgomery County has no garage-conversion rule. Whether you can convert a garage to living space is governed by your…
Read full rule →Philadelphia
Some RestrictionsPhiladelphia does not have a standalone garage-conversion ordinance, but a detached garage is the prime candidate for…
Read full rule →Tiny Homes
Zoning rules for tiny houses on wheels and foundations, including minimum square footage requirements and where they can be placed.