When we purchased our home we were told by the home inspector that we would need to add insulation in the attic, not relizing that a home built 20 years ago could be so far from code today. We had roughly 8" of insulation our a/c would run non stop day night. We had GNI come in and add an additional 16 inchs on top of what we had and what a difference it makes a/c finally cycles likes its suppossed to and the house is more comfortable then ever. GNI was very clean and prompt job well done and cheaper then another quote we had gotten. Definitely recommend GNI.