RUDOFSKY'S BOOK

As Bernard Rudofsky proclaimed in his manual on Non-Pedigreed Architecture in 1964, a respectful look back to the “fairy-tale countries” and their “communal enterprise” should urgently happen; exotic built environments not produced by a few intellectuals or specialists, but by the spontaneous and continuing activity of a whole people with a common heritage, acting under a community of experience.

“One of the most radical solutions in the field of shelter is represented by the underground towns and villages in the Chinese loess belt. Loess is silt, transported and deposited by the wind. Because of its great softness and high porosity (45%), it can be easily carved. [...] The dark squares in the flat landscape are pits [...] about the size of a tennis court. Their vertical sides are 25 to 30 feet high. L-shaped staircases lead to the apartmments below whose rooms are about 30 feet deep and 15 feet wide, and measure about 15 feet to the top of the vaulted ceiling. They are lighted and aired by openings that give onto the courtyard.” 
 [from LeopoldLambert's boiteaoutils on B. Rudofsky's Architecture without architects]

The floor/roof has a double function: shelter and crop field. Neither additional air-conditioning nor heating is required, due to natural thermal lag kept in the soil mass. Furthermore, grain from the fields may be dried above ground, and afterwards storaged downstairs in the cave dwelling, simply by letting it directly fall into the storage room, through a hole on the floor/roof.