Sealing your ductwork

I have found that the biggest savings on your electrical bills can come from the simplest things. Every time you turn on the media these days there are ads that tell you to upgrade to a more efficient HVAC system. There's a lot to be said about investing in a better unit. What's not mentioned so much is the ductwork for the unit. But when you want to save money that's the place you want to look first. I'm not sure about the rest of the country, but there's a lot of leaky A/C ducts around Columbia, SC. Everytime a friend of mine complains about the power bill, I suggest that we look. Some of them have the ductwork under the house. We open up the crawl space door and stick out heads under there. Cool under here isn't it? That's your air conditioning leaking out of the ducts. Usually I get an incredulous stare. What? That's not the real reason my A/C isn't working right is it? Can't be! For you guys that have your ductwork in the attic, crawl up there and have a feel around the joints while it's running. You might actually feel the air coming out of the cracks. Now think. If the air is leaking out up here, and the return air comes from inside the house, and there's not quite enough.... then the extra would get sucked in from .... outside. Viola! Now you realize that the best HVAC system that leaks maybe 15% of the air into the wrong place, is at least 15% less efficient than it's suppossed to be. Horrifying, but fixable. They make a mastic that the HVAC guy uses. Just start painting it around the leaks in the pipes. Don't forget the inside of the return where your filter goes, and the gaps around where the ducts enter the conditioned part of the house, either in the ceiling or in the flooring. If you really want to get serious about it, an energy rater can test the integrity of the ductwork with a ductblaster test. A trained HVAC guy can seal it up, and then they test again to see how much better it is. Best money you may ever spend.