Lifting Slabs with Polyurethane

Concrete repair services specializing in lifting and leveling slabs have been around since the 1930s. There has been and still is high demand for this service. The newer method of accomplishing this with polyurethane foam can lead to healthy profits.

One contributor to the high demand is the Americans with Disabilities Act. This law mandates the repair of trip hazards from sunken or heaved concrete in public areas. With literally billions of square feet of concrete in the U.S., many of the slabs are old and out of alignment, pitched incorrectly, and in desperate need of repair. Whether it is governmental, commercial, or residential, customers are looking for a cost-effective solution to this problem.

Repair options

The first question is always, replace or repair? Concrete replacement is expensive. It is simple math. Concrete contractors must make up to three trips to a location to replace a simple slab of concrete with removal, framing, pouring, removal of forming material, and cutting of joints. Add to this the ever-growing problem of environmental constraints on concrete disposal and the replacement cost of a simple 10×10-foot driveway or pool deck can be upwards of $1,000.

Repair of misaligned slab panels has historically been achieved by mudjacking or slabjacking. This is the process of injecting a mud/slurry mix under concrete slabs with a specialized hydraulically powered mud pump to lift the concrete. Contractors drill 1 5/8-inch holes in slabs and inject the slurry under the slab, building up enough pressure to lift the concrete. This technique allows contractors to lift, pitch, or level any unrestrained slabs.

A new game

A newer way to lift, level, and stabilize concrete slabs, that has been used for over a decade now, is replacing the mud with polyurethane foam. With this technique contractors inject the polyurethane foam under the concrete slab. The expansion of the foam is what lifts or moves the slab.

Specialized polyurethane foams have been designed that have optimal expansion characteristics, set up speed, and adhesion to provide contractors with ideal control of the lifting process. Unlike with mudjacking, the technician drills fewer smaller (5/8-inch) holes, leaving a cleaner looking job than with mudjacking.