Insulated concrete forms were used as the walls for the basement, first floor and half way up the second floor, with conventional framing above.
North Tacoma Owner-Built Home
The exterior walls are thicker up to the mid-point of the second floor, as the ICF walls are more than twice as thick as the conventional framing above.
Insulated Concrete Blocks were used to build the exterior walls starting up to the middle of the second floor. The blocks are 10 inch thick and are made from extruded foam insulation with horizontal and vertical cores for concrete.