Below Grade Waterproofing
Positive-side protection under hydrostatic pressure
What below grade waterproofing actually involves
Anything built below the surrounding grade sits in the water table's path. Below grade waterproofing treats the positive, soil-facing side of foundation walls and under-slab areas so water is blocked before it enters the assembly. We install blindside, sheet, and fluid-applied systems on new construction and retrofit projects, and we always pair the membrane with a drainage plan — a membrane alone under standing water is only half a system.
Every project starts the same way: we look at the property, establish what water is doing and where it is entering, and only then specify a system. That order matters — a correctly installed product solving the wrong problem still leaves you with a wet building.
Included in every below grade waterproofing project
- Blindside, sheet, and fluid-applied membrane systems
- Under-slab vapor and waterproofing barriers
- Footing-to-wall and cold joint detailing
- Drainage board and perimeter drain integration
- Tie-hole, penetration, and pipe boot sealing
- Waterstop installation at construction joints
Four steps from first call to sign-off
Site & Water Table Review
We assess grade, soil, drainage, and the water conditions the assembly will actually face.
Surface Preparation
Walls and footings are cleaned and repaired so the membrane bonds to solid, sound concrete.
System Installation
Membrane is installed with reinforced detailing at every joint, corner, and penetration.
Drainage & Backfill
Protection and drainage layers are added, then backfill is placed carefully to avoid damaging the system.
The difference a properly built assembly makes
Waterproofing is buried work. Once the backfill, topping slab, or tile goes over it, nobody sees the detailing again — which is exactly why the details have to be right the first time.
Diagnosed First
We confirm where water is genuinely entering before specifying anything, so the work targets a cause rather than a symptom.
Matched to Conditions
Substrate, exposure, and water pressure decide the system. The same product is not right for every property.
Prepared Properly
Profiled, cleaned, moisture-tested surfaces. Preparation is where most failed waterproofing jobs actually went wrong.
Tested & Documented
Flood tests, electronic detection, and photo records so you have proof the assembly performs before it is covered up.
Detail-driven from start to finish
Durable waterproofing comes from disciplined habits, not premium product names. Here is the standard we hold ourselves to on every project.
A Written Scope
You get the system, the sequence, and the expected result in writing before work begins.
Substrate Preparation
Grinding, profiling, and repair to a sound surface — never a coating applied over unsound concrete.
Reinforced Detailing
Corners, drains, penetrations, and joints get reinforcement, because that is where assemblies fail.
Site Protection
Landscaping, hardscape, finishes, and adjacent surfaces are protected for the length of the project.
Verification Before Close-Out
Testing under real conditions, then a walkthrough so nothing gets buried on assumption.
Questions, answered
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Share a few details about the property and we will come back with clear next steps — usually the same business day.