You are correct. My house was designed & built by O'Neil Ford. He was very heavily into the housing for the masses movement post-WWII. He was the principle architect for the 1968 Hemisfair here. Among the other oddities of my house was that it was originally heated and cooled with central plant usiong ammonia coolant. There were 4 seperate air handlers located in different parts of the house. The central plant was about the size of a VW bug. I have no idea how efficient is was, as the house was retrofitted with conventional HVAC long before I got it. It is a flat roofed house with 4' eaves all around. Despite having huge windows, it has very little sun load.