duct=hole in wall=bad!

[dr_penner]

So I will be doing my duct work tomorrow. I have my staggered stud wall with two layers of drywall on the outside. I plan to (gulp!) cut a circular hole in the wall between the upright 2x4 studs. Through this I will stuff the circular 6" flex duct which will connect with the main duct for air circulation.

The gaps between the duct and the wall hole will be stuffed with expanding foam spray to hopefully seal it up. Once the flex duct enters the wall it will bend 90 degrees and travel the height of the wall before entering the room. Again it will have to bend 90 degrees and traverse two layers of material, sealed with goop.

I can't believe there isn't a better way to do this. It really makes me nervous that I have created these thick heavy walls only to cut holes in them.

I have considered putting a baffle on the outside wall to redirect the sound as it leaves the room.

Any better ways out there? Any tips to do it right?

Kurt Penner

 

[Michael Jones]

Most ducts come out of the ceiling, not the wall.
If you're conditioning more than one room,, run a trunk line for each room, do not feed each room off of one trunk. That's a sure fire way to kill your iso.
Another technique is to use oversized ducts. Six inches is very small for an A/C duct. Being so small, I would expect it would whistle when the blower is on.
You could also build a fur-down from floor to ceiling and have the duct penetrate the fur-down. Or build a fur-down at ceiling height, running paralell to the floor, and house the duct in there.