Inject Polyurethane Foam to Lift Concrete

What happens here

With the equipment set up, begin injecting small, controlled amounts of polyurethane foam under the concrete slab. The operator will monitor the slab for movement, using their fingers to feel subtle shifts before they are visible. This tactile feedback allows for precise control of the lift, preventing over-lifting or cracking. The foam expands beneath the slab, lifting it like a 'pillow' from underneath. The process involves injecting, waiting 10-15 seconds for the foam to set and observe the lift, and then repeating as needed until the desired elevation is achieved (e.g., an 1/8 to a 1/4 inch lift). Multiple injection points may be used across a larger slab to control the pitch and angle for proper drainage or to eliminate tripping hazards.

Goal: Lift the sunken concrete slab to the desired elevation with controlled foam injection.