Accessory Structures in Pennsylvania (2026)
34 rules on the books across Pennsylvania, 12 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 →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 →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 →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 →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 →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 →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.
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 →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.