Passive Solar house: The proof is in the pudding

When I last posted here the weather outside was getting pretty cold and the house I am working on still had no heat. Well we still don't have our heating system up and running yet and the house is maintaining pretty comfortable temperatures. THE LOWEST INSIDE TEMPERATURE EXPERIENCED WAS 41.9F WITH NO HEAT AND A LOW OF -4.5F

We experienced some pretty cold weather over the last few weeks and the house hasn't dropped by that much. The coldest inside temperature reached was 41.9F, that only after 3 cloudy days, highs in the lower 20's and low's at or below zero, with the lowest temp of -4.5F.
Two consecutive sunny days and the house is back up into the mid fifty's during the day and night time lows in the upper 40's. I shot some video when the temps went down to the lowest, I just haven't had the time to edit and post the vid's yet. I'll get to it soon, it is kind of tough to edit the video down to a 10min length, when I seem to be a bit long winded, I'll have to break it into 2 video's.
So, here we are in late January with no heating system installed in the house and I'm not really worried. I was early on, but once I saw how well the house performed under unusually cold conditions, I'm not worried about the pipes freezing. Hopefully the heating guy will show up tomorrow, it is starting to hold up progress on the job. Not that we need heat to work in the house but some of our finishing products need 60F heat just to work. We still have some work to finish on the inside like the interior doors and baseboard, cabinets installed, finish plumbing and the floors.
The floors are being finished with an acid stain concrete and we have been preparing them over the last few days. If you have never seen an acid stained concrete floor you might be surprised at how they look. I'll post some pictures as we complete the floors I think you will be pleasantly surprised at how warm and attractive they are. It's not just about the look, it's also about the energy. By using this finish for the floor, we add no resistance to the heat radiating from the floor. With no resistance we can lower the water temperature we need to heat the house. In turn this makes the geothermal heat pump work more efficiently and lowers the heating bill even further. This is where architectural design meets engineering in house planning, when these two work together the result is not only attractive but functional as well.

What is it that lets this house stay so warm, without heat, when it's so cold outside? There are a couple of things that are key, the insulation, the orientation, the thermal mass windows and the air sealing. Those 4 things when thought about carefully in the design phase and executed in the construction phase have enabled this house to almost heat itself. Not quite but with a very efficient heating system, maybe some solar panels and the use of geothermal energy the energy bills will be much lower than I originally expected. I originally thought the heating for this house would cost around $700 annually, but after seeing how well the house maintains without any heat, I am convinced that it will be at least 25-30% less than expected. We will see, I will be monitoring the house over the next few years and see just how much energy the house uses annually.
THE PROOF WILL BE IN THE PUDDING.

Tom Pittsley
ecobuilder@aol.com
www.eebt.org