Don’t Cool Your Attic
I was helping a friend install some light fixtures in his house Saturday and it required that we spend some time in his attic. The house is 25+ years old, in good shape overall. As we were climbing through his attic, I was talking to him about my interest in energy savings and the good progress we’ve been making on reducing electricity consumption in our home. About the time he asked me for some recommendations on his house, I literally stumbled over a gaping hole in the air duct in his attic.
After catching myself from falling through the ceiling, I inspected the problem. As the air conditioner was running at the time, I could feel cold air coming from a 6″ wide gap between sections of ductwork. To make matters worse, there was no insulation on this section of ductwork. This is a big problem. My friend is paying a lot of money to cool his attic, albeit unintentionally. I know the attic is the place you store all your precious items that you can’t bear to part with, but is it really necessary to heat/cool the space? Of course not!
Actually, since it was getting warm in the attic by this time, the cool breeze was welcome. We finished the lighting install and then discussed what he needed to do to correct the problem. Below are the things I would do to solve this issue:
- Use mastic or metallic tape designed for ductwork (not duct tape!!!) . Mastic is a liquid adhesive used as a sealant on ductwork. It provides an extremely strong bond to the ductwork. Metallic tape specifically designed for ductwork would probably be my choice for this type of repair since it is easier to work with, portable, and works quite well. Any home improvement store will sell the right type of tape for this application. Do not use regular duct tape on this type of ductwork. Duct tape, normally gray in color, is what you use around the house. My same friend was using duct tape to temporarily hold on a fiberglass bumper on his vehicle until he could get it repaired. Great for bumpers, bad for ductwork.
- Insulate the duct. Most residential ductwork is insulated, but poorly done. My recommendation to my friend was to buy a roll of insulation (inexpensive at a home improvement store) and wrap the ductwork to keep the cool air in the duct. Any extra can be used to double-wrap a portion of the duct for added insulation.
Double Wrap Ductwork for Greater Savings
Double-wrapping your ductwork is a great project for a beginning do-it-yourselfer. All you need is a sharp utility knife, a few rolls of insulation, and a few rolls of the same tape used on the ductwork (see above). Use a small piece of plywood to lay across your ceiling rafters as a safe place to sit or stand as you work. Depending on how much ductwork you have, this project should take one day of your weekend. The savings could be 10-20% on your heating and cooling bills. Since HVAC costs are the largest components of most homeowner’s energy bills, the savings could be significant. Total cost for this project should be in the $250-$500 range depending on how much ductwork you have.
I hope everyone had a great 4th of July holiday. Have a great day!
Filed under: Small Changes