Not So Big
I was struck by the fairly small size of these rooms. However, they were probably easy to heat and would have provided protection from animals. On the other hand, this particular room may have been for storage only. Since Walnut Creek is thought to have flowed only part of the year, the inhabitants may have stored a 100 day water supply in clay pots.
I am most impressed by the great location chosen which eliminated the need for a back wall and roof.
Walnut Canyon National Monument