Epoxy vs. polyurethane concrete repair. Do you use epoxy to repair cracks? Do you use polyurethane resin or polyurethane foam to repair cracks? Which solution is better and why?
Epoxies are used for dry cracks that need structural repairs. Polyurethanes, the right one, are for all other cracks.
Epoxy is a very strong material – and not very forgiving. Epoxy can not be used where water is present and can not be used on cracks that were or are still leaking. Epoxies take a long time to cure and harden and for that reason, a good amount of the epoxy will flow out the backside of the crack requiring you to use more material than required or to refill the crack again. If your concrete is not in need of structural repair, epoxies are not needed.
Polyurethanes are fast curing and a more popular method of crack repair. Not all polyurethanes are treated equal. It is important that when choosing a polyurethane kit you consider the following:
- Can the polyurethane resin be used on wet cracks, dry cracks, or both?
- Can the polyurethane resin be used for high pressure and low pressure applications?
- Will the polyurethane resin seal out water?
- Does the polyurethane resin use aluminum injection ports or plastic surface ports?
- How much does the polyurethane resin expand once in the crack?