ADU Rules in McKeesport, Pennsylvania

McKeesport is a post-industrial city in Allegheny County situated at the confluence of the Monongahela River and the Youghiogheny River (commonly called the "Yough"), approximately 15 miles southeast of Pittsburgh. With a population that has declined from over 55,000 at its peak to approximately 18,000 today, McKeesport is one of the most dramatic examples of steel industry collapse in the Mon Valley. The city's National Tube Works (later United States Steel) once employed tens of thousands; the plant is long closed. McKeesport is part of the Pittsburgh metropolitan area and participates in regional revitalization efforts.

No Pennsylvania Statewide ADU Law

Pennsylvania has not enacted statewide ADU preemption legislation. Under the Pennsylvania Municipalities Planning Code (MPC), all zoning authority rests with local municipalities. McKeesport's ADU rules are governed entirely by the McKeesport Zoning Ordinance.

McKeesport's Housing Context

McKeesport's population loss has left a substantial inventory of vacant lots and underutilized housing. The remaining housing stock includes older rowhouses, detached single-family homes, and some multi-family structures, much of it built in the early to mid-20th century. For ADU purposes:

• Rehabilitation opportunities: McKeesport's lower property values and existing housing stock create potential for accessory apartment conversions at lower cost than in more expensive markets.
• Detached ADUs: Properties with detached garages or carriage houses offer conversion potential.
• Blight and vacancy: The prevalence of vacant and abandoned properties means site assessment and structural evaluation are especially important before investing in rehabilitation.

Zoning Districts and ADU Rules

McKeesport's zoning ordinance divides the city into residential, commercial, and industrial districts. For ADU purposes:

• Single-family residential districts: Accessory structures generally permitted; conversion to a separate dwelling unit may require special exception or variance.
• Multi-family residential districts: More permissive of additional units.
• Setbacks and lot coverage: Accessory structures must comply with minimum setbacks and maximum lot coverage by district.
• Height: Accessory structures are typically limited in height relative to the primary structure.

Contact the Department of Community Development to confirm your specific zoning district.

River Confluence and Flood Zones

McKeesport's location at the Monongahela-Youghiogheny confluence creates flood risk for riverfront and low-lying areas. Key considerations:

• Properties near either river may be in FEMA Special Flood Hazard Areas.
• New construction and substantial improvements in flood zones must comply with floodplain ordinance requirements, including base flood elevation.
• Check your property at FEMA's Flood Map Service Center (msc.fema.gov).

Pittsburgh Topography

Like much of the Mon Valley, McKeesport has significant topographic variation — river valleys surrounded by hillside residential neighborhoods. Steep slope areas may impose additional construction requirements similar to Pittsburgh's steep slope overlay regulations. Retaining walls, grading, and stormwater management must be addressed in hillside development.

Environmental Conditions

McKeesport's industrial legacy may have left contaminated soils in and around former industrial areas. Before significant ground disturbance:

• Consider a Phase I Environmental Site Assessment for properties with industrial history.
• Lead-based paint rules apply to pre-1978 housing (EPA RRP rules).

Permit Process

1. Zoning determination: Contact the Department of Community Development for your district designation and ADU rules.
2. Flood zone check: Verify flood zone status via FEMA maps.
3. Building permit: Apply to the Code Enforcement Office.
4. Zoning Hearing Board: Required for variances or special exceptions.

Contact

• City of McKeesport: (412) 675-5016, mckeesport-pa.gov
• Code Enforcement Office: 500 Fifth Avenue, McKeesport, PA 15132
• Allegheny County Economic Development: (412) 350-1000 (county-level resources)

Disclaimer: Zoning regulations change frequently. Verify all information directly with the McKeesport Department of Community Development and the current McKeesport Zoning Ordinance before making any development decisions.