Wednesday, October 14, 2015

Duct, Duct, Duct, Insulate - Insulating Your Ductwork

Have you ever taken a shower and the mirror starts to fog up? For almost all of us, we have experienced this at least one time in our life, probably more often than not. You might open a window, wipe it down with a towel, or think to yourself that you need a better exhaust fan (Air King can help with that!). What a lot of people dont think about is that same steam that is causing your mirror to fog over is also going through your ducting. This presents a prime opportunity for condensation to form within your ducting. Condensation in the ducting forms when the hot steam from the shower passes through the cooler ducting, causing the steam (water vapor) to turn into a liquid form (water). This is especially true in cooler climates of the country. A very simple fix is to use insulated ducting as well as placing insulation around and on top of the actual exhaust fan (Make sure to check the rating of your exhaust fan as to how much insulation can be placed on top of it. Generally fans are rated for at least an R40 factor). By using insulated ducting it does not allow the air flowing through it to cool fast enough to cause condensation.

What is the big deal with condensation? Condensation can be harmful in many ways. Anytime you have sitting water, the potential for mold and bacteria growth exists, so you are working against one of the main reasons you have an exhaust fan in the first place. Another issue is depending on the situation you could cause enough condensation to form that it starts to drip out of your fan and possibly cause damage to the ceiling material around the fan.

Air King, as well as the Home Ventilation Institute and ENERGY STAR® all strongly recommend that insulated ducting be used with all exhaust fans, so take a minute and check to see if your fans ducting is insulated or not. Your fans ducting will thank you!

Want to learn more? Take a look at our other topics or click on the Learning Center tab of the Air King main website at


  1. Hello,
    I liked your post very much...Its defining all about air purification systems with the help of ducts...Very informative post...Thank you too much.....

  2. You guys are really awesome. Before i did not know how to get rid of mold in air ducts. I was so tensed for this. I can not live happily. But now i know many things about this problem and also can solve this by myself. Thank you again guys.