Siding, window, door and deck questions and answers for Pennsylvania homeowners

Updated November 10, 2026 · KeystoneProGuide editorial team

Does a siding or window contractor need a license in Pennsylvania?

There is no state license, but there is mandatory registration with the Attorney General for anyone doing home improvements worth $5,000 or more a year. Siding, windows, doors and porches are named in the law. The full rules are in what Pennsylvania requires.

How do I check that a contractor is registered?

Look for the number, PA followed by digits, which must appear on the contractor's ads, estimates and contracts. Check it on the Attorney General's contractor search or by calling 1-888-520-6680. Registration is not an endorsement of quality.

Does the contract have to be in writing?

Yes, for any home improvement over $500. Under the Home Improvement Consumer Protection Act, a contract that is not written, legible and signed, and that lacks the contractor's registration number, cannot be enforced against you. It must also give start and finish dates, the materials and specifications, the total price and notice of your right to cancel.

How big a deposit can a contractor ask for?

On a contract over $5,000, no more than one-third of the price, or one-third plus the cost of special order materials named in the contract. No payment may be taken before the contract is signed. The Attorney General suggests paying the rest as the work progresses, with the final payment on completion.

Can I cancel after I sign?

Yes, within three business days of signing, wherever you signed and without penalty. The Attorney General reported in May 2026 that the Pennsylvania Supreme Court held you can cancel by any means, including a phone call, if the contractor actually gets the notice. If you signed at home, the FTC's Cooling-Off Rule also gives three days for many home sales.

Do I need a permit to replace windows or siding?

Often not, but your municipality decides. The state regulation does not apply to alterations without structural changes, and says a minor framing change to replace existing windows or doors is not a structural change; installing vinyl or aluminum siding on an existing home is also outside it. Local ordinances can still require permits, so ask your township or borough.

Does a deck need a permit?

A deck needs one unless it is uncovered and its floor is no more than 30 inches above grade. In Philadelphia, a residential deck up to 216 square feet can get an EZ permit without plans.

What is different about older homes?

If your home was built before 1978, the EPA requires paid contractors who disturb paint to be lead-safe certified, and it says window replacement is always covered. Old siding and trim may also contain asbestos; the EPA says you generally cannot tell by looking, and that undamaged material left undisturbed is not likely to pose a health risk.

Will new windows cut my energy bills in half?

Not according to the federal sources. ENERGY STAR says replacing single-pane windows with certified ones lowers bills by an average of up to 13 percent nationwide. The FTC settled charges in 2012 against five window sellers over claims of savings as high as half.

Should I repair old windows instead of replacing them?

For historic windows, the National Park Service says they can often be repaired, that caulking and weatherstripping should come first, and that a good storm window over an old window can perform about as well as a new replacement, citing a 2002 study. For other windows, the condition of the frame and sash decides it.

Is there still a federal tax credit for windows and doors?

The IRS says the energy efficient home improvement credit covered improvements made through December 31, 2025. For that period it was capped at $600 a year for windows and $250 per exterior door, and labor did not count.

How high must a deck railing be?

Under the 2021 International Residential Code, which Pennsylvania adopts, a guard is required where a deck, porch or stair is more than 30 inches above the ground within 36 inches of the edge. It must be at least 36 inches high, and its openings must stop a 4-inch sphere. Stair handrails sit between 34 and 38 inches.

What does exterior work cost?

National surveys put whole-house siding roughly between $8,000 and $30,000 and a replacement window at about $450 to $1,200 each. No survey publishes a Pennsylvania figure. The ranges and what moves them are in the cost guide.

How do I pick a contractor?

Check the registration, see the insurance, confirm lead-safe certification for an older home, compare at least two written bids on the same scope, and read the contract against the law. The steps are in how to choose a contractor.

Where can I find businesses near me?

Listings for all five counties are on the exterior remodeling directory page.

Sources

2008 Act 132 (Home Improvement Consumer Protection Act), Pennsylvania General Assembly
Frequently Asked Questions: Home Improvement Contractor Registration, Pennsylvania Office of Attorney General
PA Supreme Court Upholds Consumer Right-to-Cancel Home Improvement Contracts Within Three Days Regardless of Medium, Pennsylvania Office of Attorney General
Buyer's Remorse: The FTC's Cooling-Off Rule May Help, Federal Trade Commission
34 Pa. Code 403.1. Scope., Commonwealth of Pennsylvania (Pennsylvania Code)
34 Pa. Code 403.62. Permit requirements and exemptions., Commonwealth of Pennsylvania (Pennsylvania Code)
Get permits without plans (EZ permits), City of Philadelphia
Renovation, Repair and Painting Program: Contractors, U.S. Environmental Protection Agency
Residential Windows, Doors, & Skylights, ENERGY STAR (U.S. Environmental Protection Agency)
Weatherization of Historic Buildings: Repair and Upgrade Windows and Doors, National Park Service
Energy Efficient Home Improvement Credit, Internal Revenue Service
Chapter 3 Building Planning, 2021 International Residential Code, International Code Council
Protect Your Family from Exposures to Asbestos, U.S. Environmental Protection Agency
Window Marketers Settle FTC Charges That They Made Deceptive Energy Efficiency and Cost Savings Claims, Federal Trade Commission