All pane, all gain?

     The entire house now being completely fenestrated, we seized the opportunity to test out our passive solar gain. One of our hopes is that with the windows and doors installed, the interior of the house will stay warm enough to work inside comfortably. This should prove to be true on sunny days, and it will be interesting to see how it works out on partly cloudy days. We have a kerosene heater as a backup, but I figure since we have been working outside all winter, even a slightly warmer house will be an improvement.
     To test our theory, we brought our indoor/outdoor digital thermometer to the hillside and installed it in the house. Over the course of a few work days, the results have been surprising. It seems that when it is quite warm outside (around 55 degrees F), with the sun shining and the windows and doors closed, the house stayed cooler than the outside temperature. I had expected it to be warmer, with the windows magnifying the heat intake and the insulation trapping it in. Not so. The inside temp stayed about 10 degrees below the outside temp. The next day, when we opened the windows to let the warm outside air in, the inside was markedly warmer, with the temperature differential between outside and in about six or seven degrees. On both of these days, however, as evening approached and the outside temperature dropped, the inside temp held constant, eventually becoming higher then the dropping outside temp. And yesterday, with the outside hovering around 35 degrees F and no sun in sight, the inside was a constant 7 degrees warmer than the outside temp (making it a balmy 42).
     So it seems that I don’t know what the hell I am talking about. I thought that with house sealed, and our south side with plenty of windows letting in lots of sunlight, the inside would heat up markedly, and make the inside warmer then the outside. This doesn’t seem to happen when the temperature outside is above 40 or so. In one way this is a bit depressing, as I was looking forward to a warm early spring of inside work. But it does seem to bode well for a hot summer, where the house will stay relatively cool, which is a good thing, considering the whole global warming issue.
     On a side note, it is amazing how much a window can make a structure look more house-like. The transition from gaping holes in the side of the house to finished and regulated openings is quite dramatic. It is one of those moments when you feel as if you are turning a corner in construction.

Sealedup