In Alaska, much of the ground is permafrost, or frozen soil. When icy layers thaw and settle over the summertime, the cold ground becomes wet and unstable, which can cause structural damage to the foundations of commercial buildings and homes due to heat transfer from the buildings. An objective of building on permafrost is to keep the permafrost from thawing, which requires isolating the heated building from the ground.
Typical permafrost foundations include elevating the home on steel or treated wood stilts. They can also be post-on pad foundations, which means using concrete or pressure-treated wood pads to distribute the load of posts made of either wood, metal pipe, or concrete that support the building several inches to a few feet above the surface. Both types of foundations can be very expensive, require ongoing maintenance, result in cold floors, and ineffective in achieving a thermal break, so a cost- effective solution beckoned to be brought to the forefront of construction in Alaska. Spray polyurethane foam is known for its superior insulating properties when it’s applied to building envelopes, but in Alaska, innovators from the Cold Climate Research Housing Research Center (CCRHC) opted to use SPF as a means to create “foundation foam,”specifically for constructing buildings on permafrost.