Exterior excavation waterproofing in Lancaster, PA
Digging down the outside of the foundation is the bigger job, but it keeps water out of the wall instead of managing it once it is inside.
Exterior waterproofing means excavating along the outside of a foundation down to the footing, cleaning and repairing the wall, applying a waterproof membrane or coating, setting a footing drain in stone, and backfilling with material that drains. It suits Lancaster County homeowners who want the wall itself kept dry, often before finishing a basement, and whose yards leave room to dig. Because it stops water at the outside face, it's the most complete fix when the yard and budget allow it.
When does it make sense?
- You plan to finish the basement and want dry walls, not just a dry floor
- One wall leaks badly where the yard slopes toward it
- An addition or patio is being rebuilt anyway
- The wall needs outside repair, such as a deteriorated block face
- Interior options have been tried and water still comes in
What happens during the job?
- Locating utilities. Pennsylvania law requires anyone digging, homeowners included, to contact PA One Call by dialing 811 at least three business days before excavation.
- Digging to the footing. Soil comes away from the wall, often by machine, with hand work near walks, porches and utilities.
- Wall repair and membrane. Cracks and joints are repaired, then a membrane or coating goes on. On stone walls, the company should explain how its approach handles a wall that was built to breathe.
- Footing drain and backfill. A perforated drain at the footing leads to daylight or a sump, and clean stone or free-draining fill goes back in before topsoil.
- Grading. The finished ground should slope away from the house.
What should I know about limestone areas?
A footing drain collects a lot of water, and in carbonate areas the outlet matters as much as the drain. Ask where the drain will discharge and how the company avoids concentrating water in one spot, especially if the property has a history of sinkholes or depressions. Larger yard drainage changes in Lancaster County municipalities can also fall under local stormwater rules, so ask whether your township needs to be involved.
What affects the price?
- Depth to the footing and total length of wall
- Obstacles: porches, steps, decks, driveways, plantings and utility lines
- Wall condition and how much repair it needs before the membrane goes on
- Where the footing drain can discharge
- Restoring lawns, walks and landscaping afterward
The waterproofing company prices the work after an on-site look. We don't quote prices.
Where we connect you with help
Common questions
Do I need to call 811 for exterior waterproofing in Pennsylvania?
Yes. Pennsylvania requires homeowners and contractors to contact PA One Call at least three business days before digging. The company doing the excavation normally places the request.
Is exterior waterproofing better than an interior drain?
It does a different job. Exterior work keeps water out of the wall, while an interior drain manages water that gets in. The right choice depends on access, the wall, how you use the basement and cost.
Can exterior waterproofing be done on a stone foundation?
Often, but it takes care. Ask the company how it will repair the stone and mortar and how its membrane choice handles moisture in an old wall.
Related services
Background on soils, sinkholes and Pennsylvania contract rules: Lancaster County wet basement guide.
Stone walls weeping, a wet floor edge, or a pump that never rests?
Call and a Lancaster County waterproofing company will come find where the water gets in.