Historic Home Roofing in
Pennsylvania (2026 Guide)

Pennsylvania's Rich Historic Roofing Heritage

Pennsylvania has more historically significant buildings than almost any state in the union. From the colonial-era rowhouses of Philadelphia's Society Hill to the Moravian stone buildings of Bethlehem, from the Victorian mansions of Pittsburgh's Shadyside to the Germanic farmsteads of Lancaster County, the Commonwealth's architectural diversity is matched by an equally diverse range of historic roofing materials and methods. Slate, standing seam tin, copper, cedar shake, and clay tile all have deep roots in Pennsylvania's building traditions, and many of these original roofs have survived a century or more of Pennsylvania's demanding four-season climate.

Pennsylvania is home to over 2,500 properties and districts listed on the National Register of Historic Places, plus thousands more protected by local historic district ordinances. The state has a particularly strong tradition of local historic preservation, with Historic District Commissions (HDCs) operating in dozens of municipalities from Philadelphia to small boroughs. For homeowners in these districts, replacing a roof requires navigating a regulatory process governing materials, colors, and how the finished roof must appear from the public right-of-way.

The good news is that Pennsylvania offers some of the most generous financial incentives in the nation for historic roof restoration. The combination of the 20% Federal Historic Tax Credit and the 25% Pennsylvania Historic Preservation Tax Credit can offset a significant portion of the cost. Understanding how to navigate the regulatory requirements while maximizing these financial incentives is the key to a successful historic roofing project in Pennsylvania.

Philadelphia Historic District Roofing Requirements

Philadelphia has 17 locally designated historic districts and numerous individual landmarks regulated by the Philadelphia Historical Commission (PHC). The Commission's review authority covers all exterior alterations visible from a public right-of-way, including roof replacement.

Society Hill: Philadelphia's premier colonial-era neighborhood features predominantly 18th and 19th century rowhouses originally roofed in slate, standing seam tin (terne-plate), or wood shingles. The Society Hill Historic District has among the strictest roofing standards in the state. Slate must be replaced with matching color, size, and profile. Standing seam roofs must use terne-coated stainless steel or approved equivalent in traditional pan-and-batten profiles. Synthetic alternatives are evaluated case-by-case and more likely approved for non-street-visible slopes.

Germantown: This northwest Philadelphia neighborhood contains one of the densest concentrations of historic stone buildings in the United States. Many homes feature steeply pitched roofs originally covered in Pennsylvania slate. The Germantown Historic District is somewhat more flexible than Society Hill. High-quality architectural shingles in dark colors may be approved for properties previously re-roofed with non-original materials, though slate remains preferred for properties retaining their original slate roofing.

Old City: Buildings spanning the 18th through 20th centuries with a mix of flat and sloped roofs. Flat roofs are generally not regulated for material choice since they are not visible from the street. Sloped roofs on contributing structures require Commission review with slate and standing seam metal most commonly approved.

Rittenhouse-Fitler, Spring Garden, and Diamond Street: Victorian-era districts with elaborate rooflines featuring dormers, turrets, and decorative metalwork. Reviews pay close attention to preserving historic roof profiles and details. Dormers must be maintained in original configuration and decorative elements preserved or replicated. Copper and standing seam metal in traditional colors are strongly preferred for visible flashings and accent roofing.

The approval process: All roof work in Philadelphia historic districts requires a permit from L&I, routed through the Historical Commission. In-kind replacement can be approved administratively within 4-6 weeks. Material changes require a formal hearing before the Architectural Committee, meeting monthly with 45+ days notice. Prepare a materials sample board showing proposed material alongside existing material for comparison.

Bethlehem, Lancaster County, and Beyond

Bethlehem's Moravian District: Established in 1741, this is one of the most significant 18th-century historic sites in the United States. Designated a National Historic Landmark in 2012, the stone and timber buildings feature steeply pitched roofs with Moravian tile, slate, and standing seam metal maintained for nearly three centuries. The Bethlehem Historic Conservation Commission exercises rigorous review authority. Slate must match original color, thickness, and exposure. Standing seam must use terne-coated stainless steel or copper in traditional profiles.

Lehigh Valley: Beyond Bethlehem, numerous smaller historic districts in Easton, Allentown, and surrounding boroughs have less restrictive requirements but still require review of material changes on contributing structures. The region's slate quarry heritage means locally quarried slate has particular cultural significance and is preferred for restoration work.

Lancaster County: Germanic farmsteads, covered bridges, and small-town commercial buildings feature slate, standing seam metal, and cedar shakes. Several boroughs (Lancaster City, Strasburg, Lititz, Ephrata) operate local historic districts. The agricultural context means practical considerations often favor standing seam metal over slate. The Lancaster Heritage area has been increasingly receptive to high-quality painted metal systems replicating traditional terne plate.

Pittsburgh historic districts: The Mexican War Streets, Shadyside, and Manchester districts contain Victorian and Edwardian homes with complex rooflines. Pittsburgh's Historic Review Commission reviews exterior changes including roofing on designated landmarks and within historic districts. Slate and standing seam metal are preferred for visible slopes. The steep topography of Pittsburgh neighborhoods creates unique access challenges that affect historic roofing costs.

Approved Roofing Materials for Pennsylvania Historic Homes

Tax Credits for Historic Roof Restoration in Pennsylvania

Federal Historic Tax Credit (20%): Administered by the National Park Service with PA SHPO, this provides a 20% income tax credit on qualified rehabilitation expenditures for income-producing properties listed on the National Register. Roofing work qualifies if it meets the Secretary of the Interior's Standards for Rehabilitation. The credit is claimed in the tax year the building is placed in service after rehabilitation.

Pennsylvania Historic Preservation Tax Credit (25%): Created by Act 55 of 2012, this provides a 25% tax credit (capped at $500,000 per project) for qualified rehabilitation in designated areas. Unlike the federal credit, it can apply to owner-occupied residential properties. The credit is transferable -- homeowners who cannot use the full credit can sell them at 85-90 cents on the dollar. Properties must be listed on the National Register or contribute to a listed district.

Example calculation: A Society Hill homeowner replaces a 2,000-sqft slate roof with new Pennsylvania slate and copper flashings. Total qualified cost: $60,000. Federal credit (20%): $12,000. PA state credit (25%): $15,000. Total credits: $27,000, reducing effective cost from $60,000 to $33,000. At $33,000 for a 100+ year slate roof, the per-year cost is ~$330 -- comparable to replacing asphalt shingles every 25 years at $12,000 each ($480/year).

Critical: pre-approval required. Both programs require scope of work review and approval before construction begins. Starting before receiving Part 2 approval (federal) or commitment letter (PA state) disqualifies the project. The process takes 2-4 months. Work with a tax credit consultant or preservation architect to maximize approval chances.

Working with Historic District Commissions

1. Research before you apply. Obtain your district's design guidelines specifying acceptable materials, colors, and profiles.
2. Document existing condition. Photograph the entire roof from multiple angles with close-ups of material and deterioration to strengthen your application.
3. Propose in-kind when possible. Same material, same color, same profile is the fastest path to approval.
4. Prepare material samples. Bring physical samples of proposed material alongside existing material for commission review.
5. Hire a contractor with HDC experience. Their participation adds credibility and addresses technical questions from commissioners.
6. Attend the hearing. Be prepared to explain material choices, street appearance, and what historic fabric will be preserved or altered.

Timeline: Administrative approvals take 4-6 weeks. Formal hearings are monthly with 45-60 days advance notice. Modifications add 30-60 days. Budget 3-6 months total for complex projects. Starting work before approval can result in fines, required removal of unauthorized work, and tax credit disqualification.

Structural Considerations for Historic Roof Replacement

Historic homes were built with construction methods and structural timber that differ from modern framing. Before committing to heavy materials like natural slate, have a structural engineer evaluate the roof framing. This is especially important for pre-1900 homes that may have been altered over the decades.

Load considerations: Natural slate weighs 800-1,500 lbs/square (100 sqft). If the home originally had slate and the framing is intact, it was built to support that load. If re-roofed with shingles (225-350 lbs/square) at some point, switching back to slate requires structural assessment. Framing may have deteriorated or been modified.

Synthetic slate as a structural solution: At 200-400 lbs/square (comparable to asphalt shingles), synthetic slate can be installed on virtually any existing structure without modification, saving $5,000-$15,000 in reinforcement while achieving a slate-like appearance many HDCs will approve.

Roof deck assessment: Historic decks typically consist of solid board sheathing (1x6 or 1x8 pine) rather than plywood. These may be excellent (old-growth pine is remarkably durable) or have rot and insect damage. Budget $40-$60 per board for replacement. Some HDCs may require retaining historic board sheathing rather than replacing with plywood.

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