/// Service
Foundation Waterproofing
Interior French drain, exterior membrane, sump systems, vapor barriers. We solve the water problem so the structural problem doesn't come back.
/// What's included
Engineered. Documented. Warrantied.
- 01Hydrostatic pressure analysis to size the system correctly
- 02Interior perimeter French drain tied to twin-pump sump system
- 03Exterior dimple membrane and drain tile where conditions require
- 04Vapor barriers and dehumidifiers to control residual moisture
- 05Written no-seepage warranty backed by a real company that answers the phone
/// Typical investment
$4,500 – $15,000 typical
Exact number after on-site assessment.
/// Process
4 Steps. No Theatre.
01
Diagnose
Water intrusion source identified — hydrostatic, surface runoff, or seasonal water table.
02
Design
System sized to the actual water volume. Not a template kit.
03
Install
Interior French drain, drainage matting, sump pits, battery-backed twin pumps, vapor barrier.
04
Warranty
Tested with a garden hose simulating storm load. Written warranty stays with the home.
/// Questions
FAQ.
01Why not just seal the outside?+
Exterior sealing works for new construction. On existing homes it requires full excavation, costs 3× more, and often doesn't outperform interior systems. We use exterior only when conditions demand it.
02What if my sump pump fails?+
We install twin pumps (primary + battery backup) so a single-pump failure never causes flooding. We also offer annual maintenance visits.
/// Related Services
The Other Six Fixes.
/// Book
Free Assessment.
Engineered Report.
A LI Foundation Co. tech will be on-site within a week. Assessment is free, report is included, no pitch at the end.
(516) 529-6996/// Request