It’s unfortunate that the common cloth-backed tape people can purchase in stores is commonly known as duct tape, because this has led to some major misunderstandings. “Duct tape” isn’t actually useful for ducts at all. It works for many other things, from closing boxes to temporary fixes for wood and plumbing products. When it comes to ductwork… don’t even think about it!
In fact, don’t even think about trying to seal your ducts on your own in any fashion. This is a job that requires professionals: they can accurately locate the air leaks in the ducts and use special tools to effectively seal them.
A bit more on that “duct tape” confusion
Gray cloth-backed tape has a long history going back to World War I, where it was used to seal ammo boxes. The tape picked up the name duck tape, probably because it was first backed with duck cloth, or because its water-resistance properties reminded people of water flowing off a duck’s back. Later, however, the name duck became mistaken for duct and the tape was advertised as useful for repairing broken ducts. But laboratory tests have shown this simply isn’t true. In tests, duct tape quickly turns brittle on ducts material because of the temperature changes and falls apart in only a month.
Professional duct sealing techniques
Trained ventilation technicians do use something called duct tape to close off gaps in ductwork. However, it’s a type of metallic tape that creates a firm mechanical seal resistant to temperature changes. Another kind of tool that professionals use is mastic sealant, which is a resin-based adhesive applied with a caulking gun. Mastic is flexible and leaves a smooth surface behind. Which tool a professional uses on your ducts will depend on the duct material and the preferences of the professional. If you hire the right people, you shouldn’t have any reason to worry about the results.
Freedom Heating & Air Conditioning, Inc. offers professional duct testing and duct sealing in Minneapolis, MN and the surrounding areas.