Serving the Denver Metro area since 1976. We lift up sunken cement floors with a soil-cement grout. This does not decay and you get a 5 year warranty - which, if it hasn't moved in 5 years, it won't ever move. Mudjacking with a soil-cement grout is the way to go. Regardless of how far it has dropped, or how big the void, a two car garage would cost half the price to mudjack with a soil-cement grout but at least double the price to lift using foam, and if there is a large void underneath, the price will go up. Thus leaving the homeowner with a shocking price. Another reason to pick a soil-cement grout is because fewer pilot holes are used, where with foam, there will be several pilot holes - at least one every 2 feet.