I bet you were wondering when my husband Mike was going to contribute to this effort. Here is his explanation of how changes in the floor and foundation in our new home in southern Colorado will help to maintain a warm, even temperature in the winter:

Our new house will be passive solar with a direct gain system. This means that in winter, the sun will shine in through our south-facing windows, directly heating our well-insulated concrete floors.

The concrete floors will be 6 inches thick and covered with ceramic tile. The tile will be a dark color to absorb the heat from the sun.

While 4 inches is the optimum thickness for the concrete, additional thickness will add some extra heat storage capacity. We thickened our floor to 6 inches to accommodate a few thermal storage water tubes. You can put colored water in them and they look GREAT, but they can be quite heavy.   Please see blue examples at right… more about these later!

The concrete floor is where the light from the sun is converted to heat and is absorbed into the concrete. The floor moderates the house temperature by its mass, which gives off heat when the house air temperature is low and absorbs heat when the house air temperature is high.

The concrete floor will be insulated from the ground with foam insulation, seen in blue in this photo. It is insulated underneath and around the edges. In addition to this, the foundation walls will be insulated on the inside. This creates a longer path for the heat to escape the house, making the ground under the floor warmer, thus cutting down on heat loss into the earth.