I finally got back to the thread.
Working from the architecture inward:
My brother's goal was to preserve the looks of the 1920 craftsman home, while adding a large garage and connecting addition with the geothermal system. He put the knees on the gable end and kept the details. Even though the garage is taller than the house, it is set back enough that the scale of it looks right from the street side.
Funny thing about the bay window there. We had scaffolding there in that notch to install the metal roofing, and I lost my screw gun on the garage roof. It skipped down the valley, off the handrail, and through the bay window onto the kitchen table. OOPS!