Sandy, it was a 2 story 3 season room that I took over for my sewing area. We added heating/cooling, but the floor is a deck with spacing between the boards. When I sew I have to put something down, but, as you mentioned the lower level has about a million pins. There are huge windows on 2 walls, so I cover the bins & bolts with sun block drapery lining. That's what those orange clamps are for on the shelving unit.