Standard Heavy Duty Construction: All wood framing , 4 x 4 pressure treated skids. Floor joist are 2 x 4's @ 16" o.c. Decking is 5/8" plywood. Side walls are constructed with 2 x 4 studs at @16" o.c. The exterior is constructed with 5/8" rough sawn texture 1-11. Roofs consist of 2 x 4's @ 16" o.c. rafters with 1/2" plywood and 25yr shingles. There is a double plate on top of studs for rafters. All standard windows are jalousie, crank out type.