One of the most overlooked ways to make your HVAC system more efficient is to have tight ductwork. Leaky ductwork can make your energy bill rise 10-percent or more, and it may also cause heating or cooling issues in the room that the ductwork serves. However, properly sealing ductwork can be a do-it-yourself project, provided that you have the right tools and use the correct materials.
The first thing you need to know about sealing ducts is that you never use cloth duct tape to seal leaky duct seams. The adhesive on cloth duct tape will quickly fail and the tape will begin to sag, creating the same leaking problem that you had before. So if you want tight ductwork, and you want to do it right, never use cloth duct tape on duct work seams.
The correct way to make your ductwork tight is a two-step process. The first step is to push the ducts together firmly and then insert three or four sheet metal screws where the ducts overlap. You can either drill pilot holes first, or use self-tapping screws if you don’t have a drill bit. Once attached with screws, the ducts will never come apart.
The next step is to seal the seams to make them air tight. You can use one of two ways to do this. Either use an aluminum metal duct tape, that can be fully wrapped around the entire seam, or better yet, use a mastic sealant. A mastic sealant is applied with a disposable brush and literally covers the entire seam. Once applied, it sticks to the ductwork, but never truly hardens. This allows it to flex with the ductwork during heating and cooling cycles.
Having tight ductwork for your HVAC system guarantees that every room your ductwork serves will be heated and cooled effectively, and you’ll be saving money through efficiency, each and every time your HVAC system is in use.
For the best in expert advice about sealing and servicing your ductwork, contact Arpi’s Plumbing and Heating. We have been servicing the Calgary area for more than 50 years.
Our goal is to help educate our customers in Calgary, Alberta about energy and home comfort issues (specific to HVAC systems). For more information about ductwork and other HVAC topics, download our free Home Comfort Resource guide. Image courtesy of Shutterstock