The choice between epoxy and polyurethane for foundation crack sealing depends on whether you have a structural issue or a water leakage problem. Each material serves a distinct purpose:

• Epoxy Injection: This is the preferred choice for structural repairs in dry, dormant cracks. Epoxy delivers a high-strength bond that can exceed the tensile capacity of the concrete itself, effectively restoring the load-bearing integrity of foundation walls and slabs.
• Polyurethane Injection: This is a more cost-effective, flexible solution designed primarily for waterproofing. Polyurethane expands upon contact with moisture, making it ideal for sealing actively leaking cracks. Because it remains flexible, it can accommodate minor foundation movement that might cause rigid epoxy to fail.

While the epoxy injection crack repair cost is typically higher due to the meticulous labor and surface preparation required, it offers a permanent structural fix for non-moving cracks. Conversely, polyurethane is faster to install and better suited for wet conditions.

Because no two foundations are alike, it is recommended to have a professional on-site inspection to determine if your cracks are active or dormant before selecting a material.

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