PU Injection Grouting
A targeted fix for active, pressurized leaks — injected directly into the source rather than applied over the surface.
What it is
Polyurethane (PU) injection grouting is a technique where a specialized polyurethane resin is injected under pressure directly into a crack, joint or void in concrete. On contact with water, the resin reacts and expands, filling the void and forming a flexible, watertight seal from within the structure.
How it works
Small injection ports are drilled along the line of the crack or joint. Polyurethane resin is pumped in under pressure using specialized equipment, forcing it to travel through the crack network. As it contacts moisture, it foams and expands, sealing the pathway water was using to get through.
When it's used
- Active, pressurized leaks — water visibly seeping through under pressure
- Construction joints and cold joints between concrete pours
- Basement and retaining wall leaks below the water table
- Cracks that continue to move slightly, since cured PU stays flexible
Advantages
- Can be applied while the structure is still leaking, without waiting for it to dry
- Reaches deep into narrow cracks that surface coatings can't penetrate
- Cures flexible, accommodating minor structural movement without re-cracking
- Minimally invasive — no large-scale demolition required
Not sure which system your problem needs?
The right system depends on your specific site condition. Show us the problem and we'll confirm the right approach.
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