How To Install Flex Duct In Attic

Pull the webbing back toward the joist to form a loop.

How to install flex duct in attic.

Mastic comes in a bucket air duct sealant comes in a tube they re basically the same thing. The straps that hold up the flex duct need to be no less than 1 5. This is a short training video to show technicians and homeowners how to properly install flex duct to plenums. Continue throughout the line until air can be discharged at the exit.

Sometimes the best route for a flexible duct run is up and over an obstruction. The supports need to be at the manufacturer s recommended spacing but no longer than 4 maximum. Slide the webbing under the flex duct. Isley s home service inc.

Installing flexible or insulated duct is an easy diy project. Pull both sides of your ductwork so that the insulation is free of the ends and then wrap duct tape around both pieces. To prevent problems use saddles or straps to support at regular intervals 4c 4d follow the manufacturer s instructions but in case they get lost here is a list of best practices for. In this video i use mastic and air duct sealant t.

Raise the webbing until the bottom of the flex duct sits 1 2 to 1 inch off the bottom of the attic. I ll show you how to get the job done right. Spread it around with either your fingers or a disposable chip brush or disposable paint brush. Attach the joint into the middle and secure with more duct work.

But without proper support ducts can develops sags or kinks that reduce airflow 4a 4b. The official recommendation from the adc is that flex ducts should sag no more than 1 2 per foot of length between supports.