Moth master

Our small house was built in the style of a solar envelope, something sprouted from the genius mind of a so-called "Ekotect" who was not actually an energy engineer. As I understand it, the idea is something like this: passive solar heat enters via windows and rises into the attic, then flows down the hollow north wall into the crawl space filled with rocks which absorb the heat...?? Maybe it worked in 1981, but by the time we moved in, theory and reality didn't quite sync up.