Siding, windows and decks in Chester County, PA: newer homes, historic villages and 73 local rulebooks
Updated · KeystoneProGuide editorial team
What makes Chester County different for exterior work?
It holds two kinds of housing side by side: a large stock of newer homes, and historic towns and villages whose buildings go back to the colonial era. Which one you live in changes the questions to ask. Over both sits a local government map of 73 municipalities, each setting its own permit practice and, in some places, its own historic rules.
How new is the housing?
Newer than the state as a whole. The Census Bureau estimates that 10.7 percent of Chester County's homes were built since 2010, against 6.1 percent for Pennsylvania, and only 12.6 percent were first built in 1939 or earlier, against 25.0 percent statewide. The Census counts 212,491 housing units in its 2020-2024 profile; the county's own fact page gives 215,918 as of 2024, up 5,104 from 2021. The median value of an owner-occupied home is $485,600.
For a house built since 2010, two practical points follow. The EPA's lead-safe rule does not cover housing built in 1978 or later, so a contractor working on a newer home has no lead certificate to show you. And ENERGY STAR notes that some window manufacturers void the warranty if their installation instructions are not followed, so if a newer window still has its paperwork, read it before anyone else works on it. For the older houses, the reverse is true: the EPA treats window replacement in a pre-1978 home as covered work however small, and the firm must be certified.
Who sets the rules where you live?
Your municipality. The county's fact page says it is made up of 73 municipalities: one city, 15 boroughs and 57 townships. Labor and Industry says over 90% of the state's municipalities enforce the Uniform Construction Code themselves, with their own staff or a certified third-party agency.
The state regulation leaves room for local differences. It says replacing windows or doors with only a minor framing change is not a structural change, and that installing vinyl or aluminum siding on an existing house is outside its scope, in both cases "except as required by ordinances". An uncovered deck no more than 30 inches above grade needs no state permit; a higher or covered deck does. Call your township or borough building office with your address and the scope of the job, and ask whether a permit and inspection are needed.
Could your house be under historic protection?
In Chester County, more likely than many owners expect. The Planning Commission says many of the county's historic buildings stand in one of its 16 urban centers or 80 villages, and the county traces its founding to 1682, as one of the three original counties of the colony.
Two state laws let a municipality protect them. Under the Historic District Act, a municipality can create a local historic district, which the Pennsylvania Historical and Museum Commission must certify, and require a Certificate of Appropriateness before a historic building is altered, with a review board advising on each application. Under the Municipalities Planning Code, protections can sit in ordinary zoning and land development rules instead. The county's planning guidance says protections here are often built through zoning, that historic districts have often been used for concentrated historic areas in towns and villages, and that several municipalities regulate historic resources in their ordinances. It gives the Birmingham Road Corridor Local Historic District as one example.
The planning commission also notes that historic districts are often wrongly assumed to impose strict design rules such as color limits, and that the law lets each municipality set its own. The only way to know what applies to your windows, siding or porch is to ask your municipality before ordering materials.
How do you check a contractor here?
At state level. The Attorney General's contractor search can be filtered to Chester County and by type of work, and shows active registrations only. The Attorney General adds that a registration is not an endorsement of quality, and advises checking references, getting more than one bid and looking for Better Business Bureau complaints. The Chester County Planning Commission's office, at 601 Westtown Road in West Chester (610-344-6285), is a starting point for questions about historic resources, not about contractors.
Where next?
The statewide registration, contract and deposit rules are in what Pennsylvania requires, and businesses serving the county are on the Chester County exterior remodeling page.
Sources
- 2020-2024 ACS 5-Year Narrative Profile: Chester County, Pennsylvania, U.S. Census Bureau
- 2020-2024 ACS 5-Year Narrative Profile: Pennsylvania, U.S. Census Bureau
- Facts About Chester County, Chester County
- Historic Preservation, Chester County Planning Commission
- eTools: Historic Resource Protection Standards, Chester County Planning Commission
- Planning and Ordinances, Pennsylvania Historical and Museum 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)
- Uniform Construction Code, Pennsylvania Department of Labor and Industry
- Renovation, Repair and Painting Program: Contractors, U.S. Environmental Protection Agency
- Residential Windows, Doors, & Skylights, ENERGY STAR (U.S. Environmental Protection Agency)
- Home Improvement Contractor Search, Pennsylvania Office of Attorney General
- Home Improvement Contractor Verification, Pennsylvania Office of Attorney General