A good many of our timber frame homes have been built on Superior Walls precast foundation systems. The walls feature a continuous layer of insulation bonded directly to the precast concrete, resulting in high energy efficiency and low thermal transfer. A few other reasons we like them: minimal on-site waste as each foundation is custom-made, we find they are easy to wire and finish with drywall, and the systems are made in the USA (with one facility just 15 miles from our East Coast shop).