Recent Review: The ductwork in my two-story home is in sand under the slab. While the ductwork is indestructible, the galvanized steel connectors are not. After 45 years, they have become rusty and have a few spots that allow sand to enter my system. A common solution is to discontinue the use of the the floor ducts and install ductwork in the ceiling. This is relatively simple in a one-story home, but can be problematic in a two story. Years ago, I watched a commercial plumbing company eliminate leaks in a city's underground pipe leaks by sending in a video camera and installing liners without digging. I searched for a similar solution for my home, found Enviroduct, and am satsified with the result. Tip: Communicate with Vince via texting. He doesn't take calls while he's working and it is difficult for him to answer all his messages after hours.