Just finished and filled a canoe shelter. The building is 8 ft wide, 20 ft long. Those are 4 x 4's in the ground set with concrete for the corners. Two 4 x 6 in the center hold both the center roof and the canoes. I used 2 x 4 x 8ft for cross pieces to hold three canoes stacked. I could have squeezed in four per side and might go back later to do just that. The end holds msc gear and four folding kayaks. About $600 in materials. Recycled siding.