Heaping insulation over the ducts is fine in dry climates but can cause condensation on the duct insulation jacket in humid climates.
Diy attic ductwork.
The doe s building america program recommends beds buried encapsulated ducts.
By spraying closed cell foam on the ducts before burying them in attic insulation you prevent the condensation problem.
To install preformed duct insulation start by disconnecting an elbow to expose the end of the duct.
Well in the comments dave roberts a senior engineer at the national renewable energy lab nrel wrote about a paper he co authored last year and included a link to it.
Wrap the insulation around the duct and then pinch the seam closed.
Only qualified contractors should perform changes to your duct system.
Here are the itemized costs for the most common types of ductwork and supplies needed to complete installation.
Both can be added to uninsulated attics or layered over existing material.
Adding heat runs in a basement may change the airflow in the ductwork going to other rooms.
Make sure your ductwork insulation has a proper vapor barrier to avoid mold and moisture problems.
Well if they re not properly sealed they are stealing money from you.
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.
Install dampers at the registers to adjust airflow.
Remember that article i wrote about ducts installed against the roof deck and how i said it was probably the absolute worst single location for installing ducts.
Attach a second air duct to the first by peeling back the insulation.
Remove existing ductwork where needed.
Cost of installation supplies.
Once you ve decided which type is best for you examine the material options and prices to home in on the right product.
Test your co detectors to alert you to any carbon monoxide problems.
Secure the insulation with short strips of foil tape.
I called out the original hvac company and they took a look and said they saw no water.
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.
If those dampers can t be accessed from below you ll want to install them close enough to the register so that you can reach them through the register opening.
If the air duct isn t long enough it is possible to add extra length.
Apply a long strip of foil tape along the seam in the insulation.
Possibly in an unfinished basement.
Run the new flexible air duct under the house from the floor return to the underside of the air handler and attach to the metal vent box or plenum image 1.
Up against the deck may be the worst place in the attic to.
For diy attic insulation you ve got two choices.
The attic ductwork is flex duct work.
You all have duct work either in your attic or crawlspace or something like that.
Loose fill or batt the common term for blanket insulation.
Diy duct sealing only.
It was new when the ac was put in 7 years ago.
When repairing or installing ductwork always consult an hvac professional first.