The best thing about this bookcase from a design perspective is that it only enchroaches on the living room 3 inches. The bookcase replaces an unsightly railing that was inevetably covered in clothes in this family home. The stairs are exceptionally wide so I built the descending book cases down the stairs to hold the body of the main bookcase above. The boxes are birch plywood edged in douglas fir. The upper case is backed and topped with solid fir tongue and groove, so the view from the kitchen at the back of the case is beautiful and clean. The trim is western maple. All the shelves are adjustable.