Interior Drain Tile Cost Calculator

An interior drain tile system — often called an interior French drain — is a perforated pipe set in gravel along the inside edge of the footing. It collects water that reaches the base of the wall and routes it to a sump pump, which lifts it out and away. Because the pipe follows the footing, the job is priced per linear foot of that perimeter, plus the installed sump.

This is the interior cousin of an exterior trench drain around the yard. If you are pricing the outdoor version, use the French drain cost calculator; the two share the same per-foot logic but run in very different places.

What the per-foot price covers

Interior drain tile normally means breaking out the slab edge, digging a shallow trench along the footing, laying perforated pipe in washed gravel, tying it into a sump pit, and patching the concrete. The installed $/ft you enter should bundle those steps — confirm on your quote what is and is not included (for example, whether a vapor board or a new sump pit is separate). A sump pump is almost always required, so price it too; the sump pump cost calculator breaks that out line by line. Interior systems manage water that has already reached the footing; if the goal is to keep water away from the wall in the first place, an exterior approach or better yard drainage may be the honest fix, and ongoing water or wall movement is a reason to bring in a licensed engineer.