Flex AC ducting in the attic- anyone have experience installing this? I recently got a new furnace/AC installed. I've noticed that some of my AC duct runs were damaged and had them replace at $150 a pop. There may be others. I'm going to run the AC and check for leaks. My understanding is that the material for running new ducts is very inexpensive. I'm considering doing it myself. I spoke with the installer who made it sound simple and it looked simple as I watched them make the repairs. Where the duct hits the ceiling vent, smear some glue on the inside, slide it down and attach a plastic tie. Slide the out side part of the duct over and tie it, then smear the glue around the joint. Easy, yes (no)? Thanks!