Jim Ittenbach's Adventures in Soundproofing
This phase is where the air coditioning duct issues are resolved. I had noticed
that when the band was playing, if I went upstairs the sound was always louder as you approached an air
conditioner duct. They were acting like little speakers. I had my son Aaron and his friend Mikey Menard, who
are qualified duct manufacturers and installers, design a new duct system. The main feeder duct was relplaced
with a sheet metal duct with 1" fiberglass lining inside. This duct was also wrapped on thhe outside to
reduce any vibrations that might get through what will be a ceiling with resillient channel and two layers of
5/8" sheet rock.
The feeder ducts that were tangenting of the main duct were replaced with insulated
8" flexduct. With this part of the duct system complete I can now complete the wall structures. Additionally,
I was also able to remove the flexduct and complete installing sheetrock between the joists.
Here is a view of the flexduct coming off the end of the main feed and feeding a
duct in my dning room upstairs. This was one of the ducts that seemed to act like a speaker when I came
upstairs to listen. Simply adding flexduct to this setup helped decouple the AC from the baand room. Adding a
new main feed in with insulation inide the duct and wrapping the outside will further decouple the system.
Once all the sheetrock between the joist was installed and the flexduct was
put back up, I installed the first beams. These beams enclose the AC system's main feed duct. I plan to
install 2x2 inside the beams use. Then I can use two layers of 3/4 inch plywood with quiet glue between to
close the bottom side of the beams. By using foam tape on the 2x2 and mounting with screws, I will be able to
access the duct in the future if I need to.
Later the duct work for the studio room will be installed. I wanted to feed the room with seperate feeds. If I
simply tapped of the duct that feeds the upstairs of my house I believe the sound would readily travel through the
system and make the rest of my hard work obsolete.