Conscientious builders strive to conserve energy, improve quality, and reduce costs, but few innovative building techniques fulfill all three objectives. The frost-protected shallow- footing technique is an exception. The concept is so basic I'm surprised it hasn't caught on sooner. Rather than build the footing below the frost line, you insulate the ground at the building perimeter to raise the frost line. If the ground never freezes, you no longer a deep footing. The technique has a long history of successful use in the Scandinavian countries (see "Thirty-Year Track Record"). With conventional slab construction, most heat loss occurs at the slab's edge. You can dramatically reduce heat loss by adding rigid foam insulation; but with a frost-protected shallow
