Interior basement drain tile
When water shows up where the wall meets the floor, an interior drain gives it a path to the sump instead of across the basement.
An interior drain tile system is a pipe buried just inside the foundation walls, beneath the edge of the basement slab. The crew cuts and removes a strip of concrete along the walls, digs a shallow trench beside the footing, lays perforated pipe in clean stone, and pitches it toward a sump pit. Water that comes through the wall or rises at the footing drops into the pipe instead of spreading over the floor. The pump sends it outside, and the trench is closed with new concrete.
When does an interior system make sense?
It's the usual answer when water enters along the floor edge on more than one wall, or when the foundation is fieldstone or hollow block that can't be sealed from inside. It deals with water after it reaches the house rather than keeping it off the wall, but it doesn't mean tearing up a driveway, porch or flower bed. On the closely spaced lots of Elmira's Near Westside, Eastside and Southside, where the house next door may be a few feet away, it's often the only practical choice.
What happens on installation day?
- Tracing the water. The company finds the entry points and checks for cracked, bowed or crumbling walls.
- Clearing the edges. Shelving, stored items and finished walls along the perimeter have to be moved or removed.
- Trench and pipe. The slab is cut, stone and pipe go in, and many installers add a plastic flange or dimpled membrane on the wall so water running down it ends up in the drain.
- Sump. The pipe empties into a lined pit with a pump and a discharge line to the yard.
- Patching. The trench is filled with concrete and the floor is usable again.
What should I ask before I sign?
- Which walls get drain tile, and why not the others?
- How is the pipe protected from silt, and is there a cleanout port?
- Where will the pump discharge, and is that allowed where I live?
- If there's a radon mitigation pipe through the slab, how will the new system work with it?
- Does this need a building permit, and who will get it?
- What does the warranty cover, and does it transfer if I sell?
What affects the price?
- How many linear feet of wall need drain tile
- Slab thickness and how easily equipment can get into the basement
- Finished walls, flooring or built-ins that have to come out
- The pump, any battery backup, and the length of the discharge line
Prices come from the waterproofing company once someone has stood in your basement, checked the walls, the floor joint and the sump, and looked at where roof and yard water goes outside. We don't quote prices, and an honest number can't be given over the phone before anyone has seen the water's path.
Where we connect you with help
Common questions
Will interior drain tile make my basement walls dry?
It keeps the floor dry, not necessarily the wall. The drain catches water once it has come through or under the foundation; adding a dimpled wall membrane guides wall seepage down into the pipe, though the masonry behind it can stay damp.
Can drain tile go in under a finished basement?
It can, but the bottom foot or two of drywall, framing and flooring along the perimeter normally comes out first. Get the tear-out and rebuild written into the proposal so nobody is surprised.
Related services
More background: Chemung County basement water guide.
Water at the base of the wall, a crack that drips, or a sump you don't trust?
Call and a Chemung County waterproofing company will come trace where the water is getting in.