The land on which the house sat was clay. When clay is wet it is a gloopy mess, when it dries and hardens the ground can split. So that the house did not move as the ground dried, the foundations of the house were dropped down over a metre in places so that the house rested on bedrock. In this photo you can see the green oak arch, covered to protect it against the weather - the house was built through a terrible winter, you can see the mess of wet clay in the foreground.
The garage, seen here with the underlay for the roof just attached, was a simple wood box construction.