Last minute jitters re:Cellouse insulation

Started by Sebastian Ernest on 16 August 2003. 4 replies. In the Library under Walls, floors and ceilings.

Originally posted at johnlsayers.com, topic 580.

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