✔ Restore it to be as Good as New!
✔ Immediately Walk on it.
✔ A Fraction of the cost of replacement
✔ Additional Landscaping repair is not required
What foam jacking is best for
There are many times when foam jacking is the only repair process that will address a problem. Here are some of the times when foam jacking is best:
Large slabs (typically bigger than 100 square feet) are best repaired with foam jacking because polyurethane can travel under the entire slab from just one or two injection holes, creating a more diffuse lifting force than grout. This speeds up work and lessens the chance of cracking. Faster reacting lower density foams typically start to expand within a few seconds of injection, so they are good for concentrated lifting. Slower reacting, higher density foams can travel as a liquid for up to 45 seconds before starting to expand and harden. This allows them to lift extremely large areas, as the liquid is injected at 600 psi, which forces it into what can be very small spaces under the slab.
Sensitive or expensive surfaces
Because foam jacking uses small (dime-size) holes that can be placed infrequently, it is an ideal repair method for settled slabs which have decorative coatings, surface treatments or other characteristics, such as brick and stone overlays. Injection holes can be patched with stained concrete to blend in with floor coverings. For repairing slab floors with wood, we use a 1″ hole saw to cut a small access area to the floor, which can then be puttied back into place after lifting is completed. For carpeted areas, three sides of 2″ squares can be cut to reveal floor and then be glued back down after injection.
Because high density polyurethane is stored and transported as a liquid which then expands, a single non-CDL box truck can easily transport more than 80 cubic yards of expanded material. The equivalent for slab jacking grout would require more than 6 large dump truck loads and onsite handling equipment. Raw polyurethane material is transported in standard chemical totes, so is easily transported, stored and handled on job sites.
Because of its high expansion force and ability to spread under large areas of slabs and structures before expanding, high density polyurethane can lift extremely heavy slabs with ease. These include roadway slabs, bridge approaches, rail crossings and slabs with heavy loads, such as machinery bases and floors with backup battery power packs.
Areas where cleanliness is important
Due to the small, infrequent holes, dustless drilling is easy. Additionally, because there is a mechanical connection between the injection equipment and the slab, not material is exposed to the surface or surroundings. Automatic, mechanical valves on the injection equipment prevent leakage of material when not injecting.
Load sensitive areas
The most common cause of slab settlement is inadequate compaction or bearing capacity of the underlying soils. Because high density polyurethane is lightweight (typically 2.5 to 6 pounds per cubic foot), there is very little additional weight transferred to the underlying soil as part of repairs. This helps to minimize the chances of resettlement. Sand-based and cementitious grouts used for slab jacking or pressure grouting typically weigh more than 100 pounds per cubic foot, so the weight savings with foam jacking are significant.