Structural Engineer Hanif Kara believes that if we could find a way of adapting the human body to sleep vertically, we would eliminate a lot of the world’s pressing problems. A single adult takes about 7 m2 of bedroom space to be comfortable, so 70 adults could stand shoulder to shoulder in the same volume. This reduction in footprint means less building, less cooling and less heating, even if all other areas of the home such as corridors and kitchens remain the same. Photo: Shan Pillay