Progress, page 37
The foam panels we used for the walls below slab level are 11 inches wide and have a nominal 8
inch core for the rebar and concrete. That gives us a really strong wall for the foundation and
retaining wall on the downhill side of the house. We need less strength and more insulation now
that we are above the slab, however, so we just took delivery of a large batch of panels that are
11 inches wide but instead have a nominal 6 inch core. That gives an extra inch of foam on both
sides of the wall. Here you can see the comparison between the two versions.