What happens during a window, siding or deck project, from contract to final inspection

Updated November 10, 2026 · KeystoneProGuide editorial team

What are the stages of an exterior job?

Most siding, window, door and deck projects run through the same sequence: a signed contract and a three-day wait, ordering and permits, preparation of the site, the work itself, inspections where the job needs them, and a walk-through before the last payment. How long each stage takes depends on the product and your municipality, and none of the official sources gives a typical number of days for the work, so ask your contractor for the schedule in writing. The contract must at least give approximate start and completion dates.

What happens when you sign?

You should leave with a completed copy of the contract, free, at the moment of signing; the Home Improvement Consumer Protection Act requires it. Then the clock starts on your right to rescind: three business days, wherever you signed. The Attorney General reported in May 2026 that the state Supreme Court held you can cancel by any means, including by phone, as long as the contractor actually gets the notice.

If a deposit is taken, it can only be taken after signing, and on a contract over $5,000 it may not exceed one-third of the price plus any special order materials named in the contract.

What happens while the product is ordered?

Two things run in parallel: the order and the permit. Anything that is not a stock item, is ordered for your contract and cannot be returned for credit is special order material under the act, which is why the contract lists it separately from the deposit.

If the job needs a permit, it is applied for now. In most of Pennsylvania that means your municipality's building code office or its third-party agency, since Labor and Industry says over 90% of the state's 2,562 municipalities enforce the code locally. In Philadelphia, the city says most applications without plans are processed within 5 business days, and a contractor with a current license, insurance and tax account may get an EZ permit for windows, doors or wall covering at once. Ask to see the permit before work starts; in Philadelphia the inspection contact is printed on it.

What does the first day look like in an older home?

If the house was built before 1978 and the job disturbs paint, the EPA's lead rule shapes the setup. The firm must have given you the Renovate Right pamphlet before starting. The EPA's work practices then require containing the work area so dust and debris cannot leave it, and forbid open-flame burning and power tools without HEPA exhaust control. Copies of the certified renovator's training certificates must be on the job site. Window replacement is always covered by the rule, however small.

The EPA's guidance for do-it-yourselfers describes the same aims in household terms: plastic sheeting, closed doors and windows, and keeping family members out of the work area until cleanup is complete. If old siding or trim might contain asbestos, the EPA's advice is that it should be assessed by a trained, accredited professional before it is cut or torn off, not during.

What should happen during a window or door installation?

The window or door should go in to the manufacturer's instructions. ENERGY STAR says certified products must come with them, that even the best windows can be drafty if poorly installed, and that some manufacturers void the warranty if the instructions are not followed.

The code adds the weather protection around the unit. The International Residential Code, which Pennsylvania adopts, requires flashing at exterior window and door openings that carries water out to the wall surface or the water-resistive barrier, and air sealing around the opening on the inside of the gap. Where the manufacturer gives no flashing details, the code calls for pan flashing at the sill. If you can, look at an opening before the trim goes back on.

What should happen during siding work?

Under the code, the wall behind the siding needs a continuous water-resistive barrier, such as No. 15 felt or a listed house wrap, and flashing at openings, above projecting wood trim and wherever a porch, deck or stairs attach to a wood-frame wall. Vinyl siding must be certified to ASTM D3679 and installed to the manufacturer's instructions. When the old siding comes off, the sheathing underneath is exposed; that is the moment any rot repair agreed in the contract, or a change order for one, should happen, with the price in writing before the work is covered again.

What should happen when a deck is built?

Footings come first. The code requires deck footings at least 12 inches below undisturbed ground, and, for a deck attached to a frost-protected house, protection from frost, for example by going below the local frost line. If the deck needs a permit, ask the building office which inspections it requires and at what stage, before the footings are poured or the framing is covered. The ledger board that attaches the deck to the house must be at least 2 by 8 inches, fastened with galvanized or stainless bolts or lag screws, never hung on stone or brick veneer, and flashed where it meets the wall.

How does the job end?

With inspections where a permit was issued, and a walk-through. In Philadelphia, the city issues a Certificate of Approval once all required inspections pass. Elsewhere, ask your municipality what final sign-off it gives.

Before you sign anything saying the job is finished, walk every window, every wall and every board with the contract in hand. The Attorney General advises homeowners not to sign a completion certificate until all the contracted work is done to their satisfaction, and the FTC says never to make the final payment until then. If something is wrong, put it in writing; the FTC suggests following any phone call with a letter by certified mail, return receipt requested.

Questions to put to the contractor before any of this starts are in questions to ask, and the rules behind each stage are in what Pennsylvania requires.

Sources

1. 2008 Act 132 (Home Improvement Consumer Protection Act), Pennsylvania General Assembly
2. PA Supreme Court Upholds Consumer Right-to-Cancel Home Improvement Contracts Within Three Days Regardless of Medium, Pennsylvania Office of Attorney General
3. Pottstown-Based Home Improvement Contractor Jailed at Least 3 Years for Taking More than $156K for Jobs he did not Complete, Pennsylvania Office of Attorney General
4. Get permits without plans (EZ permits), City of Philadelphia
5. Uniform Construction Code, Pennsylvania Department of Labor and Industry
6. Renovation, Repair and Painting Program: Work Practices, U.S. Environmental Protection Agency
7. Renovation, Repair and Painting Program: Contractors, U.S. Environmental Protection Agency
8. Lead-Safe Renovations for DIYers, U.S. Environmental Protection Agency
9. Chapter 7 Wall Covering, 2021 International Residential Code, International Code Council
10. Chapter 5 Floors, 2021 International Residential Code, International Code Council
11. Residential Windows, Doors, & Skylights, ENERGY STAR (U.S. Environmental Protection Agency)
12. How To Avoid a Home Improvement Scam, Federal Trade Commission
13. Protect Your Family from Exposures to Asbestos, U.S. Environmental Protection Agency