The kitchen, Bulthaup island, and overhanging entrance-level comprise the remainder of the extension. A five-story double-sided, weld-free aluminum bookcase begins in the kitchen and rises through the lounge. A staircase traces every inch of it so that material can be readily accessed.  Photo 17 of 21 in A Spotlight on 10 Traditional Homes with Modern Interiors from This Dramatic London Renovation Boasts a Five-Story Bookcase