Interior basement drainage
When water pushes in where the wall meets the floor, an interior drain gives it a path out before it spreads across the basement.
An interior drainage system is a channel along the inside edge of the basement floor. The crew cuts out a strip of concrete next to the walls, digs a trench, lays perforated pipe in stone, and runs it to a sump pit. Water that seeps through the wall or comes up at the joint between wall and floor drops into the pipe and is pumped outside, instead of crossing the floor. New concrete then goes back over the trench.
When does interior drainage make sense?
It's the usual answer when water shows up along the floor edge on several walls, or when the walls themselves are old stone or block that can't be sealed from the inside. It deals with the water after it reaches the wall rather than stopping it outside, but it doesn't require digging up landscaping, porches or driveways. That matters on tight city lots and rowhouse-style blocks in Altoona, where there may be no room to dig on one or more sides.
What does the work involve?
- Inspection. The company traces where water comes in and checks the walls for cracks, bowing or loose mortar.
- Clearing the perimeter. Shelving, finished walls and stored items near the walls need to be moved.
- Trenching and pipe. The floor is cut, pipe and stone go in, and many systems add a plastic wall flange or dimple board so wall seepage runs down into the drain.
- Sump pit and pump. Water collects in a lined pit and is pumped out through a discharge line.
- New concrete. The trench is patched and the floor is ready to use again.
Questions to ask
- Which walls are getting the drain, and why those?
- How will the pipe be kept from clogging with silt over the years?
- Where will the pump discharge, and is that allowed by your municipality?
- Is a permit needed, and who will get it?
- What does the warranty cover, and does it transfer if you sell?
What affects the price?
- How many feet of wall need the drain
- Floor thickness and access for the crew
- Finished walls or flooring that have to come out
- Pump type, battery backup and discharge line length
Every price comes from the waterproofing company itself, after someone has walked the basement, checked the walls and floor edge, and looked at the gutters and grading outside. We don't quote prices, and a number given over the phone before anyone sees the house is a guess at best.
Where we connect you with help
Common questions
Will an interior drain stop my walls from getting wet?
Not completely. It catches water after it comes through or under the wall and carries it away. A wall membrane can direct that water into the drain so it doesn't run across the floor.
Can this be done in a finished basement?
Yes, but finished walls near the perimeter usually have to be removed and replaced, which adds cost. Ask for that to be spelled out in the quote.
Related services
More background: Blair County basement water guide.
Puddles by the wall, a damp smell, or a pump that won't stop?
Call and a Blair County waterproofing company will come take a look.