I have no idea why, but when my home was built, flex duct was used everywhere. The attic was a mess, there were air leaks and kinks everywherer, airflow to the farthest points was minimal, unfortunately that longest run was to the master bedroom.
This is what it looked like originally:
In Mid Feb, I had the ductwork corrected. They extended the main trunk and shortened all the flex. This was the much improved end result:
Flow is much better overall.
Since we only turned the AC on a week ago, I decided to go into the attic and look for leaks. I was not thrilled with the workmanship as I watched it unfold.
Basically I overheard the crew had lost the special staple gun required to staple the hard ductboard together, so it has no staples, but they did use a firestop adhesive 'when they remembered' which seemed odd.
They taped all the joints on the ductboard, but did not use mastic on the undersides of any joint.
I found 5 small leaks where the flex enters the ductboard truck. I'd assume that small leaks are unacceptable workmanship right? They are where the flex attaches to the butterfly damper which enters the ductboard. The dampers were not sealed/taped to the ductboard, just the tabs were bent into place. The flex was tie-wrapped to the damper, and the whole thing was coated with mastic.
so I have a few concerns.
1. The ductboard was not stapled as it appears it should have been
2. The underside of the ductboard was taped, but not sealed with mastic like all other 'easily accessible' areas.
3. Small leaks in the flex attachment.
all valid concerns?