On the other hand, its also possible for the epoxy to flow out of the backside of the crack before it has hardened if the backfill outside the wall has separated from the foundation. This can be an advantage because it allows time for the epoxy to flow into even the smallest crevices. However, epoxies cure very slowly, generally taking hours to harden. That's why epoxies are the only choice for cracks requiring structural repair. The main advantage of epoxies is their amazing compressive strength, which at 12,000 psi or greater exceeds that of most concrete. The wider the crack, the thicker the material required. Coles advice is to use whatever viscosity is needed to inject a given crack at pressures less than 40 psi. EpoxiesĮpoxies for crack injection are available in a range of viscosities, from ultra-thin to paste-like, to accommodate cracks of different widths. Here's a look at the advantages and limitations of each material. If the crack needs to be repaired only to prevent water leakage or the crack is actively leaking, a polyurethane is usually the best choice. But here are some general guidelines: If the crack needs to be structurally repaired and the area needs to be as strong or stronger than the concrete around it, use an epoxy. In many cases, either material can accomplish the task, and applicators may simply choose the material they have the most experience with. So which material is better for repairing concrete cracks: epoxy or polyurethane foam? The answer isn't always clear-cut. It can also be used to fill cracks in concrete floors and ceilings. This method is effective for filling cracks 0.002 to 1 inch wide in walls up to 12 inches thick. "For basement walls, low-pressure injection is the best way to ensure that the crack is completely filled," Cole maintains. The whole purpose is to fill the crack, from front to back, with epoxy or polyurethane. That gave him the impetus to develop a line of epoxies and polyurethane foams specifically formulated for those types of repairs. The application that seemed to show the most promise for his dual-cartridge system was low-pressure injection of cracks in concrete. "Most contractors in the Chicago area (as well as other parts of the country) warranty the injection repair for the life of the structure," he adds.Ĭole launched his company in 1987, after coming up with the concept of dual-cartridge dispensing of two-component materials using a spring-assisted dispensing tool similar to a caulking gun. More than 99% of the time, crack injection will fix the problem," says Cole. "Emecole's customers, primarily residential waterproofing contractors, have less than a 1% callback rate for crack repair work. Cole says that in the Midwest, crack injection has been an accepted way of tackling these repairs for many years, and more and more foundation repair contractors around the country are adopting the technique because it is cost-effective, reliable, and permanent. "Even if a crack is not leaking now, eventually water will find it," says Lou Cole, president of Emecole Inc., Romeoville, Ill., a manufacturer of epoxies and polyurethane foams for all types of foundation crack repair. Either way, the repair of concrete cracks in either the foundation or the slab may efficiently and effectively be completed in as little as an hour or more. The application of such materials may be completed by a basement waterproofing contractor or a do-it-yourself homeowner. For the repair of concrete floor cracks, certain epoxies and polyurea materials exists, suitable for such slab repairs. Poured foundation cracks may be repaired by using low-pressure injection of an epoxy or polyurethane foam material. Foundation and slab cracks are not only an eyesore, but they may hinder the value of the home.įortunately, there is an easy way to permanently repair such cracks without the need for costly and disruptive excavation or drain tile. More often than not, a foundation crack will widen over time and result in water seepage or possibly the loss of structural integrity. These cracks typically due to drying shrinkage, thermal movement or other causes usually are minor and result in few problems. They may also recognize cracks on the garage floor, patio or in-ground pool. Most homeowners best identify concrete cracks in their basement, either on the foundation wall or on the floor.
While concrete cracks appear to be typical, it is not recommended that they remain ignored.