In a few weeks I hope to have all the walls floors and windows cut for stacking tower room boxes. Working on the layout of my staircase, The tower will be 40 inches deep, X 20 inches wide, and 30 inches high- to match the existing house. 20 inches is fairly narrow for a 1/6 scale turning staircase. So with large doorways to other rooms on each side, a floating staircase will give the appearance of more space. The photos give a general idea but mine will be tighter. There will be landings at each end for support, as well as a window at each end.