This was the first structure I built from the ground up. It took almost one month. The shed is wired with 50 A 220 V service for running welders and heavy machinery. The foundation is 5-6 inches thick with a 16"x16" gray beam around the perimeter. It was my largest concrete pour to date — 14,000 lbs in 6 hours. The walls are 8 feet tall on the long sides and there is 10 feet of vertical open space below the rafter at the peak. The inside dimensions are 9'x15'.