How To Install Flexible Duct In Attic

The official recommendation from the adc is that flex ducts should sag no more than 1 2 per foot of length between supports.

How to install flexible duct in attic.

The first thing you want to do is take either air duct sealant or mastic and spread it around the take off. Push the core so that it. How to insulate your attic duct system step by step with video instructions as winter nears many will begin to activate their home heating system to keep the house warm in the blustery and frigid temperatures that accompany the change in seasons. The supports need to be at the manufacturer s recommended spacing but no longer than 4 maximum.

Slip the flex duct s inner core over the plenum or collar and onto the mastic glue. Pull both sides of your ductwork so that the insulation is free of the ends and then wrap duct tape around both pieces. Secure the webbing to the joist by hammering a 2 inch roofing nail through the webbing and into the side of the joist. How to hang flex duct in an attic 1.

The straps that hold up the flex duct need to be no less than 1 5. Pull down the insulation so that it covers the core. Hold the loose end of a roll of duct support webbing against the side of a roof joist sitting directly above the flex. Attach the joint into the middle and secure with more duct work.

Installing flexible duct insulated duct diy 1. Sometimes the best route for a flexible duct run is up and over an obstruction. Spread a thin layer of mastic glue onto the beaded end of the plenum or metal collar. But without proper support ducts can develops sags or kinks that reduce airflow 4a 4b.

I use the caulking gun with air duct sealant to get back in the spaces it s hard to reach with the mastic. Ensuring your attic is properly insulated is essential to this endeavor.