Doing some work in my crawl space by putting down new vapor barrier and I noticed this air duct was really loose and it ended up falling down https://imgur.com/a/bQrWOGw. I’m having trouble getting it back up. I’m not sure it was ever really secure up there.
The problem is that the diameter is 6″, but the space between the floor joists is only 5 1/2.” Is there some sort of reducer I should try using? Here shows the space between the two floor joists at this spot: https://imgur.com/a/YN2akZZ. It has these clips that help secure it: https://imgur.com/a/k8nEiB8. Feels like the air duct boot needs to be 1″ longer to really get a secure fit. Right now, it’s not getting a good secure fit because the duct itself is hitting the bottom of the floor joists.