How To Seal Ductwork In Attic

Then use a paintbrush to apply duct mastic to the joints where an elbow connects to a duct.

How to seal ductwork in attic.

This pasty thick paint like substance can be applied to cracks and gaps in your ductwork with a caulking gun and spread with a paintbrush or if using a gallon pail just scooped and applied directly with the paintbrush. Air duct sealing video transcript. Possibly in an unfinished basement. Liquid duct sealant provides a tight seal around odd shaped metal joints.

Duct sealant is another product that is commonly used to seal up duct leaks. Don t use duct tape. Use a continuous strip of foil tape to seal off all longitudinal seams along the straight runs of the duct. To seal ductwork the old fashioned way.

It s important to seal the exhaust fan well at the joint so the air doesn t bypass or leak out of the joint. This tape is known as foil tape and it s specially made for working on your furnace or your ductwork. Steps to sealing attic air ducts locate the source of the thermal leaks by inspecting the ductwork while the air conditioner is running. Before you do anything grab your rag and make sure that the area is clean before applying either mastic sealant or foil tape.

To seal this instead of regular duct tape i m going to use some acrylic faced aluminum tape. Well if they re not properly sealed they are. The tape and the caulk stick a lot better when there isn t a lot of dust there. I make sure to keep that insulation away from the adhesive face so i don t contaminate it.

Use zip ties to secure any loose ducts to the attic floor. Duct sealing by michael church here and in this video we re going to show you how and why it s very important to air seal the run of the ductwork. Make sure the duct is secure in place. Tape works especially well on fiberglass and flexible ducts as well as flat metal ducts.

Apply a generous amount of sealant mastic over the thermal leak. You all have duct work either in your attic or crawlspace or something like that. To apply insulation measure the circumference of the duct.