Replacing windows, siding or a porch on a historic house in Pennsylvania

Updated November 10, 2026 · KeystoneProGuide editorial team

Does historic status change what you can do to your house?

It can, and the rules are local. In Pennsylvania, a municipality can require approval before exterior changes to buildings in a local historic district, and Philadelphia requires approval for almost any exterior work on a property listed on its historic register. Outside those cases, an old house is simply an old house: the ordinary permit rules apply, along with federal rules such as the EPA's lead rule. The first step is to find out which situation you are in, before you sign a contract or order windows.

How do Pennsylvania municipalities regulate historic houses?

Under two state laws. The Pennsylvania Historical and Museum Commission explains that the Historic District Act lets cities, boroughs and townships designate historic districts, require owners to obtain a Certificate of Appropriateness before altering or demolishing a historic building, and appoint a Historic Architectural Review Board to review the applications. The state commission must certify a district's boundaries before the municipality can enforce that review. The second route is the Municipalities Planning Code, which lets municipalities protect historic properties through zoning, including individual properties in suburban or rural settings.

The Chester County Planning Commission's guidance shows how varied this is in practice. It says protections can sit in zoning, subdivision and land development ordinances or local historic district ordinances, and that historic districts are often wrongly assumed to impose strict design rules such as color limits, when the law lets each municipality write rules suited to it. So two historic districts in neighboring towns may treat the same window replacement differently.

How do you find out whether your house is covered?

Ask your municipality directly, giving your address. The state commission says its Cultural Resources GIS can be searched for local historic districts set up under the Historic District Act, and it has community preservation coordinators who work with municipalities on these programs. In Philadelphia, check whether the property is on the Philadelphia Register of Historic Places. Ask your contractor to confirm it too, in writing, before materials are ordered.

What does Philadelphia's Historical Commission review?

Nearly all exterior work on a registered property. The city's page lists, among the work that needs review, the installation, alteration, repair, removal, replacement or covering of:

• windows, storm windows, dormers, doors, storm doors, security doors, garage doors and shutters;
• porches, steps, stoops, ramps, decks, balconies and patios;
• facades, facade elements and trim, including cornices and doorways;
• railings, grilles and exterior light fixtures;
• masonry cleaning, painting, pointing and repair, and any change to the building's exterior appearance.

Not reviewed: standard maintenance such as scraping and painting wood trim and replacing clear window glass, gardening, and interiors not on the register.

Two of the city's permit shortcuts stop at the historic line. Its EZ permit page says one- and two-family homes need no permit for window and door replacement of the same size unless they are historic, and that masonry facade replacement is not available as an EZ permit for historic properties. Its building permit page similarly limits the list of work that often needs no permit to properties not on the historic register.

How does the review work in Philadelphia?

It is part of the building permit, and it is free. The city asks owners to contact the commission's staff during planning, at preservation@phila.gov or (215) 686-7660, so the staff can explain the process and suggest preservation techniques. Staff approve more than 90% of permit applications without referral. The rest go to the Architectural Committee and then the Historical Commission at public meetings, with photographs and drawings, and the commission may approve, approve with conditions or deny.

What does federal guidance say about siding?

That the old advice is gone. The National Park Service's 1984 brief on aluminum and vinyl siding on historic buildings was rescinded in October 2023; the Park Service says its information and guidance no longer represent best historic preservation practices. In its place, a brief on substitute materials for distinctive exterior features was revised the same year. The Park Service also publishes briefs on preserving historic wooden porches, which cover assessing condition, repair and code issues, and on exterior paint problems on historic woodwork. A local board applies its own ordinance, so ask what guidance it uses.

And about windows and doors?

Repair first where possible. The Park Service says historic windows can often be repaired or upgraded, that caulking and weatherstripping should come before any replacement, and that historic wood doors have good thermal properties and should be retained. Where storm windows are added, it says their meeting rails should line up with the historic sash and they should be painted to match, with interior storms an option for decorative windows. Where replacement is unavoidable, ENERGY STAR notes that wood frames are generally favored in historical neighborhoods.

Does the lead rule still apply?

Yes, if the house was built before 1978. The EPA's rule requires a certified firm for paid work that disturbs paint, with window replacement covered at any size. Approval from a review board does not replace that requirement.

For the choice between repair and replacement, see repair, add storms or replace; for Philadelphia's other rules, the Philadelphia guide. Listed businesses are on the exterior remodeling directory page.

Sources

1. Planning and Ordinances, Pennsylvania Historical and Museum Commission
2. Get approval for work to a historic property, City of Philadelphia
3. Get permits without plans (EZ permits), City of Philadelphia
4. Get a Building Permit, City of Philadelphia
5. eTools: Historic Resource Protection Standards, Chester County Planning Commission
6. Preservation Briefs, National Park Service
7. Weatherization of Historic Buildings: Repair and Upgrade Windows and Doors, National Park Service
8. What makes it ENERGY STAR? (Residential windows, doors and skylights), ENERGY STAR (U.S. Environmental Protection Agency)
9. Renovation, Repair and Painting Program: Contractors, U.S. Environmental Protection Agency