How To Run Flexible Ductwork In Attic

Give your ducts the proper support.

How to run flexible ductwork in attic.

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 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. I called out the original hvac company and they took a look and said they saw no water. In my experience heating ducts that run through attics cause serious problems in snow country.

Ducts should be able to run between studs in the wall and then turn into a joist bay the space between two joists. If it s not tight the friction rate jumps significantly and that means the air flow takes a hit. 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.

But without proper support ducts can develops sags or kinks that reduce airflow 4a 4b. Unfortunately this practice is all too common in our northern cold climate putting air conditioning ducts in the hottest. In warm climates it is common practice to run heating and air conditioning ducting through attic spaces simply because it is easy to do. It was new when the ac was put in 7 years ago.

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. The diagram below shows that if a flex duct has even 15 longitudinal compression the friction rate doubles. Make sure the studs and bays line up well enough to leave a clear path. 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.

Choose the right duct size and layout. Hard ducts without proper mooring will be unbalanced and unbalanced ductwork might be to blame for a number of hvac problems. The attic ductwork is flex duct work. Improperly supported flex.

For more information about the use of flexible ducts read this achrnews article about ductwork design. Don t let a contractor talk you into it. Isley s home service inc.