Why don't rabbits burrow rectangular burrows? Why didn't early man make rectagular caves?
Supposition: Architect... Client wanting single-storey house in the landscape

Phase I, Burrows . . . Purchase foamed polystyrene block 40ft. by 40ft by 15ft. and suitable burrowing tools, e.g. electric hedg-cutter, blowlamp. Block placed on site, burrowing commences, kids carving out playroom, etc., parents carving rest. Architects advising.

Phase2, Dissolve . . . House burrow completed. Enter burrow with plastic and fiberglass spray machinery,(with client) spray burrow under supervision of plastic engineer. Client chooses regions of surfaces tobe transparent or translucent, the spray mixture alters accordingly.
Phase 3, Completion . . . Shell entered by architect and service consultant and client. Client decides upon regions of lighting, wall, floor heating, sinks, power points.