Interior basement waterproofing in Columbus
When water comes in where the wall meets the floor, an interior drain catches it under the slab and sends it to a sump before it reaches the room.
What the system is
A strip of concrete about a foot wide is cut out of the floor along the foundation walls. Under it, a trench goes down to the top of the footing. Perforated pipe is laid in washed stone in that trench, sloped toward a sump basin. A dimpled plastic membrane is fastened to the lower wall so water running down the inside face drops behind it into the stone instead of onto the floor. The trench is closed with new concrete.
In block foundations we drill weep holes in the bottom course so the water sitting in the hollow cores can drain out into the system.
When it is the right call
- Water appears along the base of several walls, not at one crack.
- The leak shows after long soaking rains when the clay is saturated, not after every shower.
- The basement is block, fieldstone or poured, and the walls are structurally sound.
- Digging outside would mean tearing out patios, driveways or mature plantings.
How the day goes
Furniture and storage near the walls is moved first. The floor is sawn, the concrete broken out and carried away, the trench dug and the stone and pipe set. Most single-family basements take two to four days, depending on the length of wall and whether a new sump basin is needed. The crew runs dust control, but plan on noise during the cutting.
What it does not do
An interior drain manages water that reaches the wall; it does not stop the wall from getting wet on the outside. If a wall is cracking, bowing or crumbling, that is a structural question to settle first. And a drain does not fix roof water dumped at the foundation, so we check downspouts and grading on every inspection.
Related: Sump Pump Installation · French Drains · Exterior Waterproofing
Common questions
Will an interior drain work on a fieldstone foundation?
Yes, with more membrane work. Fieldstone lets water through at many points, so the wall membrane matters as much as the drain. We also look at the condition of the mortar before quoting.
Does the system need maintenance?
The drain itself needs little. The sump pump does: test it a few times a year and plan to replace it eventually. A battery backup protects against a power cut during a storm.
Can I finish the basement afterward?
Yes. That is one of the main reasons people choose it. Frame the new walls slightly off the membrane so it can keep draining.
Is a permit required?
Often not for interior drainage, but the building department decides. If a permit is needed for your address, we pull it.