Uretek is a ground-engineering company that is able to fix house problems by raising, re-levelling, & re-supporting sunken buildings & floors through strengthening the foundation ground. The walls of our old house were beginning to become extremely cracked, and Uretek determined that at the back of the garage, the house was actually sinking into the ground. They use a structural expanding resin which is injected into a tiny hole, which meant there was no excavation & no mess. The Uretek material they use is non-toxic & environmentally friendly. They did a great job on our house & we were very satisfied with the results. A bit pricy perhaps, but certainly the quality & results are worth it.