May 30, 2008 (Day 124)

Garage Foundation

Work began on the garage foundation. We are trying a relatively new technique to frost-proof the garage. Instead of using conventional frost footings that need to be placed 42 inches below grade in Minnesota we are using hard core foam insulation beneath a sand and gravel base. Not only is this technique less expensive, but theoretically it will prevent the entire garage floor from heaving. In a large, unconditioned, outdoor space, conventional frost footings leave the center of the garage floor potentially unprotected from frost raising the possibility that the walls will respond to cold temperature differently than parts of the floor. With the system we are using, that is less likely to happen (in theory any way).

Why do we need frost protection in our garage in the first place? We are building a small greenhouse on the west side of the garage which will have cold running water and drainage for tending the plants in the winter.

The footings for our reconstructed front steps were also poured today.