Last minute jitters re:Cellouse insulation

Sebastian Ernest · Post by **Sebastian Ernest** » Sat Aug 16, 2003 10:17 am

hello,

I am in the middle of building my studio (26' x 22') The walls are framed and the roof is on and we have all electrical and hvac run. We are now ready for insulation. I have called everywhere and cannot find Rockwool. At least here in Texas they just don't sell it. I think the EPA shut down the one plant that used to manufacture it.

It has been recommended to use Cellouse insulation at a depth of 3.5" on the walls. They say they can't spray it on the ceiling cause it won't stick so I have to insulate the ceiling with Batts to R-36.

I was told 1" of Cellouse yields an STC of about 50. Wonder what 3.5 inches do. I plan to use channel over this into the studs and then 2 layers of 5/8" gypsum.

Question: is spraying cellouse to fill the stud wall advisable, or ill advised.
Question: Shall I put a layer of torchdown roofing in between the layers of sheetrock. Torchdown is a peel and stick rubber/asphalt product used under roofs and has a R of 6.

Some one write me over the weekend and ease my jitters. I don't want to mess this up.

I posted my floorplan in case anyone is interested.

knightfly · Post by **knightfly** » Sat Aug 16, 2003 11:26 am

When you say you've called everybody, do you mean actual commercial insulation contractors or just home owner type places like Home Depot, etc? I just did a search at ask.com, my question was "mineral wool insulation in Texas - they came up with (besides a lot of crap about dogs, etc) 137 different companies just in the Dallas/Fort Worth area - granted, that doesn't mean they actually HAVE the stuff, but still, lotta places to call.

I've only seen a couple of comments on blown cellulose, and the claims were pretty good - can't comment from experience though, and evidently didn't bookmark like I should have.

I don't know how firmly cellulose packs when applied that way, so Im not sure if it's a good thing or not. Having a little pressure from insulation against inner wallboard usually HELPS isolation, because it dampens the panel resonance and decreases the "coincidence dip" which is between 2k and 4 kHz for sheet rock. Damping also helps some at low frequency. However, too MUCH contact by too tightly packed material and you LOSE effectiveness by flanking. It's kind of a tough call when you're not familiar with the particular product or method.

I personally would look some more before giving up - try ask.com and ask the question I did, I don't think my search would work for a link for you -

Also, when asking locally (commercial, NOT homeowner guys) ask about SAFB's - those work well in cavity walls... Steve

Post by **John Sayers** » Sat Aug 16, 2003 1:50 pm

welcome to the site sebastian - I'd PM Michael Jones - see his studio at
http://johnlsayers.com/Studio/Mainpage/MP-Carriage.htm

he'll know where to get it in Texas.

cheers
john

knightfly · Post by **knightfly** » Sat Aug 16, 2003 3:20 pm

Sound of vigorously slapped forehead echoing in the distance...

Post by **John Sayers** » Sat Aug 16, 2003 6:51 pm

Sound of vigorously slapped forehead echoing in the distance...

no - that's the sound made by the head of a US power company when someone mentioned maintenance.

:)

cheers
JOhn