Do this now
- Do not step into standing water if it could be in contact with outlets, appliances or the electrical panel. Have the utility or an electrician cut power first.
- If you smell gas, leave and call the gas utility or 911 from outside.
- Check whether the sump pump is running; if it has lost power, a battery backup or generator can restart it.
- Work out whether the water is clean or sewage — sewage needs professional cleanup.
- Move belongings up, then remove water and start drying with fans and a dehumidifier as soon as it is safe.
- Photograph everything before cleanup for your insurer.
What usually causes it
- Gutters and downspouts discharging next to the foundation
- Soil graded toward the house
- A failed or overwhelmed sump pump
- A high water table pushing water through the floor–wall joint and cracks
- A plumbing leak or water heater failure rather than groundwater
What a professional will do
A waterproofing contractor identifies the source before proposing a system. Many wet basements improve with gutter, downspout and grading corrections. Where groundwater is the cause, the usual answer is interior perimeter drainage to a sump pump with a battery backup; cracks and bowing walls may need structural assessment.
How to prevent it
- Extend downspouts well away from the foundation and keep gutters clean
- Regrade soil so it slopes away from the house
- Test the sump pump before the wet season and add a battery backup
- Store valuables off the basement floor
Rules and paperwork in Pennsylvania
- Pennsylvania’s Home Improvement Consumer Protection Act requires most contractors who perform home improvements to register with the Attorney General’s office and to give you a written contract for any job over $500. The registration number belongs on the estimate and the contract — ask for it.
- Building permits in Pennsylvania are issued under the Uniform Construction Code by each municipality or the inspection agency it appoints, so the local building or codes office decides what needs a permit and an inspection.
- Much of southeastern Pennsylvania is in EPA’s highest radon potential zone, and elevated levels have been found in every county. Test before finishing or sealing below-grade space; Pennsylvania certifies radon testers and mitigators through the Department of Environmental Protection.
Sources: Pennsylvania Office of Attorney General — Home Improvement Consumer Protection Act; Pennsylvania Department of Labor & Industry — Uniform Construction Code; U.S. EPA radon zone map; Pennsylvania DEP Radon Division. Rules change — confirm current requirements with the agency and with your municipality.
Frequently asked questions
Is groundwater seepage covered by homeowners insurance?
Typically not. Standard policies generally exclude groundwater and flood; sump-pump failure can be covered where you have added that endorsement. Check your policy.
Will waterproof paint fix it?
No. Coatings do not hold back water under pressure. Managing where water goes — outside first, then drainage — is what works.
Should I test for radon after waterproofing work?
Yes. Sealing and changing drainage can alter how soil gas enters, and much of southeastern Pennsylvania has high radon potential.
Go deeper
Our full basement waterproofing guide covers how the work is done, what affects the price, and what to ask before you hire, and there is more on interior drainage & sump pumps.
This guide is general information, not a substitute for a professional assessing your home. If you are unsure whether something is safe, treat it as if it is not.