Exterior, Cabin Building Type, Shipping Container Building Type, Green Roof Material, Metal Siding Material, and Flat RoofLine Poteet describes the space as “unbearably hot” before he used spray-foam insulation between the exterior walls and the interior bamboo. “Now it’s the equivalent of a steel ice chest,” he says.  Photo 89 of 101 in 101 Best Modern Cabins from Smaller in Texas