We love our conditioned air, whether it be heated or cooled. However, if you don’t have proper duct insulation, you could be radiating your money away.
The Problem of Improper Duct Insulation
Take a look at your ducts and you will immediately see the issue: Ducts are made of little more than a thin sheet of metal bent into a tube or plastic tubing with minimal thermal resistance. That metal isn’t going to provide much protection for your conditioned air, and indeed you will lose 10% to 30% of the energy put into conditioning the air through bad insulation. [1]
In the best case scenario, this simply means that you are losing money every time you run your air conditioner or heater. It could also mean that your house will never reach the temperature you want. You could lose so much of the cooled air your air conditioner has produced that the air blows out hot, or you could get a blast of cold air when you were expecting heat on a cold day. Think about it: Many homes route the duct work through the attic, and on hot days in southern climates, attic temperatures can easily reach 150 degrees. [2]
If you have plastic ducts with an R-value of 4 or greater (the tubing should have the value printed on its side), it’s not nearly as important to insulate your ducts. However, if your ducts are made of metal, you have a problem.
The Solution
Fortunately, there is a fairly simple solution to cold blows and high energy bills – installing proper duct insulation can go a long way.
Insulating your ducts is an easy and cheap project, making it great for those who want to save money by doing it themselves. Insulation installed by an HVAC specialist is usually a type of rigid foam board, [1] which novices are cautioned against installing themselves. Instead, if you plan on installing your own duct insulation, look for foil-backed roll insulation.
As ducts often run through tight spaces, be careful when choosing your insulation. Make sure that it is thin enough that, when you wrap it around the duct, you will clear any obstructions.
Installation is a matter of measuring and cutting. Find out how long the surface of your duct is and cut the batt insulation to fit. Secure the two ends together with the aptly named duct tape, and make sure that the entire duct is insulated. After taping the separate pieces of insulation to try and get the best possible seal, you are done. [3]
If you have old metal ducts, or if your plastic ducts have a low R-value or are in an extremely hot room, you should consider duct insulation. The material is relatively inexpensive, and the energy savings could be quite large. Moreover, it’s one of the easiest DIY projects you can do.
Sources:
1.http://www.energysavers.gov/your_home/insulation_airsealing/index.cfm/mytopic=11500
2. http://www.factsfacts.com/myhomerepair/ventilation.htm
3. http://www.diyhomeinsulation.com/duct.php
