State facts
Pennsylvania: homes, climate zones and who licenses the work
Pennsylvania has 5.8 million housing units. 67.2% were built before 1980, and the median year built is 1965. 69.3% of occupied homes are lived in by their owners.
How old the homes are
Pennsylvania housing units, by year built
Layers drawn to scale
Age changes what applies to a house. In general, anyone paid to do work that disturbs painted surfaces in a home built before 1978 must be certified in lead-safe work practices under the EPA's Renovation, Repair and Painting Rule, which the EPA administers directly in Pennsylvania.
How homes are heated
How homes in Pennsylvania are heated
Main heating fuel, share of 5.3 million occupied homes
- Utility gas 51.3%
- Electricity 25.3%
- Fuel oil or kerosene 14.0%
- Propane or other tank gas 5.1%
- Wood 2.1%
- Coal or coke 0.8%
- Other fuel 0.8%
- No fuel used 0.5%
- Solar energy 0.1%
Climate and building zones
The 2021 International Energy Conservation Code assigns every county a climate zone from 1 to 8 and a moisture regime: A for moist, B for dry, C for marine. Zones 7 and 8 have no letter. Here is how Pennsylvania's residents divide among them, by the county they live in.
| IECC 2021 zone | Share of residents | Counties |
|---|---|---|
| 4A | 51.2% | 14 |
| 5A | 48.8% | 53 |
ENERGY STAR rates windows, doors and skylights for four climate zones of its own. Pennsylvania spans 2: North-Central (51.2% of residents), Northern (48.8% of residents).
By NOAA's 1991–2020 climate normals, counties here average 114 days a year with a low of 32°F or colder, weighted by where people live. The range runs from 62 days in the mildest county to 173 in the coldest.
- SEER2 Requirements by State: What a New AC Must Meet
- What Size AC Do I Need? How a Load Calculation Answers It
- Do Heat Pumps Work in Cold Weather? What to Check Before Buying
- No Heat in Winter: How to Stay Safe Until the Furnace Is Fixed
- Ice Dams: Why They Leak Into Ceilings and How to Stop Them
- Crawl Space Moisture: Vented vs. Sealed Crawl Spaces
- Condensation on the Inside of Windows: Causes and Fixes
Flood risk and flood insurance
0.7% of residential structures in Pennsylvania carry a National Flood Insurance Program policy: 31,965 policies, in FEMA's count as of August 3, 2026.
In FEMA's National Risk Index, 15 of 67 counties rate high or very high for riverine flooding; 1 of 67 counties rates high or very high for coastal flooding; 2 of 67 counties rate high or very high for hurricanes.
Fire ants and termites
No county in Pennsylvania is inside the federal imported fire ant quarantine.
Who licenses the work in Pennsylvania
Before anyone starts work, check the license with the agency below. Where the state does not license a trade, cities and counties may; ask the one where the house is.
- Pest control Businesses that apply pesticides need a pesticide business license and at least one certified applicator; household pest work is category 11 (Household and health related) and termite work is category 12 (Wood destroying pests). Agency: Pennsylvania Department of Agriculture, Bureau of Plant Industry, Pesticide Programs. Who to call about pest control.
- Heating and cooling No statewide license. The state does not license most construction contractors, and no state HVAC license was found; some municipalities license contractors and trades locally. Who to call about heating and cooling.
- Window replacement and other home improvement Contractors who perform at least $5,000 worth of home improvements per year must register with the Attorney General under the Home Improvement Consumer Protection Act. Agency: Pennsylvania Office of Attorney General, Bureau of Consumer Protection. Look up a license. Who to call about window replacement.
- Mold remediation No statewide license. Pennsylvania has no state regulations about mold. Who to call about water damage and mold.
Checked 2026-09-29. Licensing rules change; the agency's own page is the authority.
Sources
- U.S. Census Bureau American Community Survey 2020–2024 5-year estimates, tables B25034, B25035, B25040 and B25003 data.census.gov
- Pacific Northwest National Laboratory Guide to Determining Climate Zone by County: Building America and IECC 2021 Updates basc.pnnl.gov
- U.S. Department of Energy Prototype Building Models (climate zones 1–8 and moisture regimes A, B, C) energycodes.gov
- ENERGY STAR Climate zones by county for windows, doors and skylights energystar.gov
- NOAA National Centers for Environmental Information U.S. Climate Normals 1991–2020, annual and seasonal ncei.noaa.gov
- Federal Emergency Management Agency OpenFEMA NFIP Residential Penetration Rates (as of 2026-08-03) fema.gov
- Federal Emergency Management Agency National Risk Index, county ratings fema.gov
- USDA Animal and Plant Health Inspection Service Imported fire ant quarantine map aphis.usda.gov
- Electronic Code of Federal Regulations 7 CFR part 301, subpart P, Imported Fire Ant ecfr.gov
- Pennsylvania Department of Agriculture, Bureau of Plant Industry, Pesticide Programs pa.gov pa.gov
- Pennsylvania Department of Agriculture, Bureau of Plant Industry, Pesticide Programs pacodeandbulletin.gov pacodeandbulletin.gov
- pa.gov pa.gov pa.gov
- Pennsylvania Office of Attorney General, Bureau of Consumer Protection attorneygeneral.gov attorneygeneral.gov
- Pennsylvania Office of Attorney General, Bureau of Consumer Protection business.pa.gov business.pa.gov
- pa.gov pa.gov pa.gov
- epa.gov epa.gov epa.gov