Addition over a Crawlspace Brrrrr! We recently built an addition to our ranch home that is on a crawlspace, The rest of the house is on a full basement. The problem is that the addition is very cold in the winter. The crawl is unheated. The ductwork that runs from the existing furnace is insulated and flexible. I feel that the air that is coming out is lukewarm at best. We've looked into in-duct fans to try to get the hot air to the addition quicker, but I'm afraid that will end up just blowing more lukewarm air and not solve the problem. Should we install another furnace to serve the addition only? Maybe heat the crawlspace? The crawl is not very deep 18-24 in. The addition is 12'x32'. I'm confused at which might be the most cost effective measure. Any suggestions would be appreciated.