Interior Basement Waterproofing
When digging outside isn't practical, we capture the water at the wall from inside and move it safely to a sump — no excavation, less disruption.
Internal drainage systems that capture water at the wall and move it safely to a sump.
Not every house can be waterproofed from the outside. Shared walls, additions, decks, finished landscaping or lot lines too tight for any access all make excavation impractical or uneconomic. An interior drainage system is the right answer in those cases: instead of stopping water at the outside face of the wall, it collects whatever comes through at the footing and carries it to a sump pump before it can reach your floor.
The system is an internal weeping tile set in a channel along the footing, a dimpled drainage membrane on the lower wall that directs seepage down into that channel, and a connection to a sump pit and pump. The floor is then re-poured. Interior work runs $120 per linear foot with a $2,800 minimum; sump pumps, battery backups and other add-ons are quoted as separate line items so you can see exactly what you're paying for.
- Interior weeping tile at the footing
- Dimpled drainage membrane on walls
- Sump pit & pump integration
- Minimal disruption to landscaping
- Ideal for finished neighbourhood lots
How an interior job goes
Open the floor along the wall
We cut and remove a strip of the basement slab along the leaking wall to expose the footing. Finished walls in that area are opened up as needed.
Interior weeping tile at the footing
Perforated weeping tile is set in clear gravel in the channel beside the footing, sloped toward the sump location so collected water flows by gravity.
Dimpled drainage membrane
Dimpled membrane is fastened to the lower wall and tucked into the drainage channel. Water that comes through the wall runs down behind the membrane and into the weeping tile — never onto your floor.
Connect to the sump
The weeping tile drains into a sump pit. If you don't have one, or yours is undersized, we install a new pit and pump — with a battery backup if you want protection during power outages.
Re-pour the floor
The channel is covered and the concrete floor re-poured flush, leaving a clean strip along the wall that can be finished over.
What the work looks like
$2,800 minimum job. Sump pump, battery backup and other add-ons quoted separately. Final price confirmed at a free on-site visit.
See Full PricingInterior Basement Waterproofing FAQs
Does interior waterproofing actually stop the leak?
It stops water from reaching your floor, which is what matters for a dry, usable basement. It doesn't stop water from entering the wall itself — only an exterior system does that — which is why we recommend exterior whenever excavation is practical, and interior when it isn't.
Do I need a sump pump with an interior system?
Yes. The internal weeping tile collects water; the sump pump is what removes it from the house. If you already have a working, properly sized pit and pump we connect to it; if not, we quote a new one as a separate line item.
How disruptive is it?
Far less than excavation. The work is inside, along one or more walls, and there's no digging in the yard. Finished walls along the affected run are opened and the floor strip is re-poured; we keep dust and debris contained.
Everything else we do
Exterior Foundation Waterproofing
Excavate, seal and shield the outside of your foundation — the permanent fix for leaky basements.
Learn more →24/7 Emergency Flood Response
Basement flooding right now? Our emergency crews answer around the clock, every day of the year.
Learn more →Sump Pump Installation & Repair
Primary pumps, battery backups and full replacements — the heart of a dry basement.
Learn more →Foundation Crack Repair
Injection and structural repair for cracked poured-concrete and block foundations.
Learn more →Weeping Tile & Drainage Systems
Window well, weeping tile and surface drainage that moves water away from your foundation.
Learn more →Need interior basement waterproofing?
Get a free, written, itemized quote — or call the 24/7 line if water is coming in right now.