Made a deer stand out of a semi sleeper and it was a HEAVY buggar. Much of the floor supports, at least in the one we used, was made of steel. The fiberglass in the walls and ceiling isn't the lightest either. We used 5/8ths inch plywood to cover the big opening, make a door, and put in a window. I think you could get a real nice house with the same square footage for MUCH less weight.