Cellulose batts; experience with?
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I just found these, and my curiosity is piqued. Anyone have any experience w/ them? I’m curious about how they are for general fit (tight? gappy?) and how they are for cutting around oddities. I am really leaning hard toward cellulose now, the more I read here and elsewhere. Batts, blown-in, or some combination thereof, depending on costs and what you get out of it. thanks. j
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I've never worked with Cell batts, but to me they have the same drawback as FG batts (or any type of batts) - they are a uniform shape that is expected to fit a potentially non-uniform stud bay. That said, a "flash and batt" approach would still work great.
Yes. Cell batts may just be more batts, but if they are more uniform than 'glass (in the few houses I've installed them in, too frequently you get a very compressed batt) and cut a tad wide, the gaposis problem could be minimized. One of the rock wool ads (FWIW) mentioned something about "special sides" made just for cavity irregularities. Dunno. I think, thermally, blown-in is tops; it always gets back to the cost vs pay back time. I am also wondering about a comment in a Cell Insul Manufact Assoc bulletin; R-value is 3.8 over a wide range of densities. If so, then a DIY blown-in wall may only have the drawback that it settles a little bit. In 3 or 5 yrs, go back in and blow in a tad more (assuming an open-cavity wall.) Simple.
Have you looked into ECOCELL cellulose batts and blankets? I used them in my home and they work great. The do not fall out of the wall and fit in the cavity very tight. Also, they do not itch like fiberglass batts and installed very easily. The cellulose batts are available in 3.5"(R13) and 5.5"(R20). Also, the batts are very dense so they absorb sound making the rooms quieter. We specifically used them in an unfinished mechanical room to quiet the noise of our furnace by my daughter's bedroom. She is sleeping much better now! The website is http://www.cmsgreen.com. The company also has a blanket material that is used to insulate unfinished basements.
TK: Thanks for the info. I have never seen any of the cell batts, as no one carries "odd" stuff up here. It is good to hear your experience w/ them, though. I may order some for interior walls. I finally was able to get Roxul and when we install them I will have a better idea of what they are.