Frugal and Energy Efficient Living

get that plastic sheeting that you use on windows to keep the warm air from getting out.

For an answer to your original question, I have a house similar to yours, with a basement that gets really cold in the winter. I have experimented with heating it and not heating it, and I have mixed feelings. The floor does stay warmer, and I assume that the warmer air is rising into the house and keeping the thermostat from going on so often. So that is a plus. But it also costs me to heat that area, and it tends to cost much more than it is saving me to heat the basement. For this reason, I chose not to bother with heating it. I will say that it is easy for me to experiment since I have a gas heater set up down there already, and all it takes is firing it up or not. But mostly it has been "not". I will say that last year, I did have it on because of the unusually cold and extended subzero winter and all the water pipes that I did not want to worry about.

I know that this is not a real answer, since I do not have definitive evidence one way or the other, but this is just my experience.