Eroded soil and voids underneath a structure can result in settlement and damage to the structure. These dangerous voids can be filled with high strength polyurethane foam that supports up to 14,000 pounds per square foot. In this video, Stabilizing a House with AP 475, you'll see the back half of a residence resting on nothing but its frame and thin air. Installation of AP 475 foam secures the structure and prevents potentially catastrophic damage. (AP 475 can also be used for lifting if the unstable soil has already caused the slab to sink.)