How To Run Flexible Ductwork In Attic

This is a short training video to show technicians and homeowners how to properly install flex duct to plenums.

How to run flexible ductwork in attic.

For more information about the use of flexible ducts read this achrnews article about ductwork design. Choose the right duct size and layout. Don t let a contractor talk you into it. Ducts should be able to run between studs in the wall and then turn into a joist bay the space between two joists.

This is an especially relevant tip for flex ducts more on that in a minute but you need to make sure any ducts in your attic have proper support. I called out the original hvac company and they took a look and said they saw no water. Hard ducts without proper mooring will be unbalanced and unbalanced ductwork might be to blame for a number of hvac problems. In this tutorial i am happy to show you how to properly install flexible duct to a register can for all you heating air conditioning ventilation do it your.

In my experience heating ducts that run through attics cause serious problems in snow country. Make sure the studs and bays line up well enough to leave a clear path. But without proper support ducts can develops sags or kinks that reduce airflow 4a 4b. The attic ductwork is flex duct work.

Improperly supported flex. If it s not tight the friction rate jumps significantly and that means the air flow takes a hit. If quiet operation and energy efficiency are very important to you you might want to go with duct board made from pressed fiberglass which is more expensive but very quiet and efficient. Recently i had another hvac company come out and put in a new bathroom vent and they told me they believed the duct work was full of water.

Sometimes the best route for a flexible duct run is up and over an obstruction. The prior owner just had a new ac system installed in which they switched from the equipment and metal ducts in the crawlspace to flex ductwork equipment in the attic where temps have regularly been in the 130 150 degrees this summer. In warm climates it is common practice to run heating and air conditioning ducting through attic spaces simply because it is easy to do. Isley s home service inc.

It was new when the ac was put in 7 years ago. 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. The diagram below shows that if a flex duct has even 15 longitudinal compression the friction rate doubles.