Polyurethane injection grouting is a process of injecting polyurethane to fill and seal cracks, joints or voids of any kind in concrete or masonry buildings. Special forms of polyurethane with expansion properties are usually used in polyurethane grouting. The purpose of polyurethane injection grouting is usually to create a waterproof barrier to stop water flow, seal cracks and joints, and fill cavities.
Depending on the compactness and strength of concrete, the injection pressure of polyurethane grouting ranges from low to high. When in contact with water or moisture commonly present in the slab, the polyurethane grout will expand to ten times its original volume to fill and seal cracks and voids. Under pressure, the grouting can penetrate deep into the concrete slab and completely seal all cracks and voids. Usually the same injection port is injected twice, and the second injection is performed after the first injection is solidified to ensure complete coverage of the grouting. It is important to perform this step to ensure that all unfilled voids injected from the first injection have been completely filled from the second injection.
Polyurethane injection grouting is a very common and cost-effective method to repair leaks in concrete substrates. Most leaks in your toilet, ceiling, basement wall, balcony, etc. can be repaired by polyurethane grouting. A common misconception is that grouting will cause the leak to "transfer" to another location. First, the leakage is caused by cracks and joint weaknesses that are common in the concrete matrix. Through polyurethane grouting, we are repairing the defects of the concrete and ensuring that the concrete returns to its original watertight state. If there are no cracks, voids or joint weaknesses, there will be no concrete leakage.
As our infrastructure ages, we are bound to suffer wear and tear and structural defects, which can lead to water leakage problems. Polyurethane grouting has been and will continue to be a very cost-effective method to repair structural defects and prevent any water seepage problems.