Exterior, House Building Type, Concrete Siding Material, and Metal Siding Material Twenty-two 12-foot-wide steel-frame modules were combined to form nine to 14-foot-high rooms that were stacked and bolted together. Ten deck modules added more than 4,700 square feet of sheltered outdoor space. Image courtesy of Jill Paider.  Photo 4 of 6 in A Desert Prefab Hits the Jackpot in Sin City