Almost every legitimate concrete crack repair comes down to four materials. Polyurethane resin is a flexible, water-activated material injected into a crack where it foams and seals — the right choice for a crack that is leaking or still moves with the seasons, because it keeps sealing as the crack breathes. Epoxy resin is a rigid structural adhesive that bonds the two faces of a dry, stable crack back together and restores the wall’s strength. Hydraulic cement is a fast-setting patching compound that cures even underwater, which makes it right for plugging tie-rod holes and gushing gaps but wrong as the permanent answer to a structural crack. Polyurethane caulk and surface sealers are flexible cosmetic fillers for hairlines that do not leak. Everything sold for crack repair is a version of one of these four.

Choosing between these is the part a product label cannot do for you, because it depends on how the crack behaves, not just how it looks.

Retail injection kits package the same polyurethane or epoxy a professional uses, just in small single-crack volumes with a manual applicator. On one simple, dry, accessible crack, a good kit can hold. The trouble is everything the kit cannot do: it cannot judge whether your crack needs flexible polyurethane or rigid epoxy, it cannot generate consistent full-depth pressure by hand, and it carries no warranty. The common result on a leaking or moving crack is a repair that re-opens within a season or two — at which point the professional repair gets done anyway, now on top of the cost of the kit and any water damage in between. A kit is a reasonable gamble on a minor dry crack; it is a false economy on a crack that is wet, moving, or near anything finished.

We carry all four materials and choose by what the crack is doing. A polyurethane injection runs $750–$1,000 per crack and an epoxy injection $850–$1,500, each in a single visit and each backed by a transferable lifetime warranty. Tie-rod and snap-tie holes, where hydraulic cement or resin is appropriate, are $75–$150 each. Every additional crack repaired on the same visit is 5% off. The assessment is free, and if your crack genuinely only needs a tube of caulk, we will tell you that rather than sell you an injection you do not need.

Pricing and discount figures on this page are our own published rates, current at the review date above. The DIY benchmark comes from our kit-vs-professional comparison. Resin behaviour reflects manufacturer technical practice for hydrophobic polyurethane and structural injection epoxy as applied by our crews; failure patterns are first-party field observations from repairs across Toronto, the GTA and Southern Ontario.