Crack Repair & Sealing

Foundation cracks are one of the most common and most ignored foundation problems. Small cracks let in water. Large cracks indicate structural movement. Either way, they need to be addressed before they get worse.

We use two primary injection methods depending on the crack type. Epoxy injection restores structural strength by bonding the crack back together. It is actually stronger than the original concrete. Polyurethane injection creates a flexible, waterproof seal that accommodates minor movement.

The injection process works from the inside of your basement or crawl space. We seal the crack surface, install injection ports, and pump the material through the ports under pressure. The material fills the entire crack from front to back, not just a surface patch.

Foundation cracks are one of the most misunderstood foundation problems. Homeowners often assume all cracks are serious, or worse, that no crack is worth worrying about. The reality is more nuanced: some cracks are cosmetic and harmless, while others indicate structural movement that requires immediate professional attention.

Hairline cracks (less than 1/16 inch wide) in new concrete are typically shrinkage cracks. As concrete cures, it shrinks slightly, and these micro-cracks appear. They are cosmetic and do not indicate structural problems. However, if a hairline crack widens over time or begins to leak water, it should be evaluated.

Wider cracks (1/8 inch or more), horizontal cracks, stair-step cracks in brick or block, and cracks that leak water are structural concerns. These cracks indicate that the foundation is under stress from settling, hydrostatic pressure, or soil movement. Before repairing the crack, the underlying cause should be identified and addressed.

Epoxy injection is used for structural cracks where restoring the concrete structural integrity is the goal. The epoxy bonds the two sides of the crack together, creating a repair that is actually stronger than the surrounding concrete. After curing, the repaired crack can transfer load as if the crack never existed.

Polyurethane injection is used for cracks where water infiltration is the primary concern. Polyurethane remains flexible after curing, which allows it to accommodate minor movement without cracking. When injected into a wet or actively leaking crack, the polyurethane reacts with water to expand and form a watertight seal.

The injection process works from the interior of the basement or crawl space. Surface ports are installed along the crack at regular intervals, and the crack surface between ports is sealed with an epoxy paste. Injection material is then pumped through the ports, starting at the lowest point and working upward until the crack is completely filled.

After injection, ask whether the crack points to a larger issue. A crack above a settling footing may need helical pier support. A crack caused by hydrostatic pressure may need drainage correction. Simply filling a crack without addressing the cause is a temporary fix that will likely fail.

The cost of crack injection depends on the length of the crack, the width, whether it is actively leaking, the injection material used (epoxy vs polyurethane), and whether the crack is part of a larger structural issue requiring additional repair. Individual crack repairs in the Shoals area typically range from $400 to $800 per crack.

If you have multiple cracks or cracks that are growing, ask for a full foundation inspection rather than just repairing the cracks individually. A pattern of cracks often tells a story about what is happening beneath your home, and understanding that story is essential to choosing the right repair strategy.

The difference between epoxy and polyurethane injection is important to understand. Epoxy is a rigid material that bonds the crack surfaces together with a strength that exceeds the original concrete. It is used when the crack is structural and the goal is to restore load transfer. Polyurethane is a flexible material that expands to fill the crack and remains elastic after curing. It is used when the crack may experience minor movement and the primary goal is waterproofing.

Crack injection is a skilled trade. The technician must clean the crack thoroughly, identify injection port spacing based on crack width, mix materials to the correct ratio, and inject at the proper pressure. Over-injection can cause the crack surface paste to blow out. Under-injection leaves voids inside the crack that allow water to penetrate. Experience and attention to detail determine whether the repair succeeds or fails.

Horizontal cracks in foundation walls are the most serious type of crack. They indicate that the wall is being pushed inward by soil pressure. Filling a horizontal crack with epoxy does not stop the soil pressure. In fact, the pressure will simply cause a new crack to form above or below the repaired one. If you have horizontal cracks, you need a structural solution (wall anchors, carbon fiber, or wall replacement) in addition to crack repair.

Diagonal cracks that radiate from the corners of windows and doors indicate that the foundation has settled unevenly. One side of the opening has dropped relative to the other, creating stress that cracks the wall. These cracks are structural and require investigation into the cause of settlement before repair. Helical piers may be needed to stabilize the settled side of the foundation before the crack is injected.