Existing multiple-family residential structure built 1922. Solid building, but no insulation in the walls.
Moving plane of heated space from semi-finished (insulated, but unheated) attic to second floor ceiling – blown in.
My choices would be Certainteed Insulsafe FG or Dense-pack cellulose.
What would you use and why?
Jeff
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Replies
I used cellulose in our house, a 1976 "split entry". Aside from the fact the cellulose is far less itchy if I ever have to go swimming in it, I like the fact that it is a fairly good infiltration blocker whereas FG blocks infiltration hardly at all.
Insulsafe (FG) is so non-itchy you can rub it on your face. The itch factor is negligible.
Jeff
I guess I'd go cellulose ... should be less expensive (a little). But there is that infiltration factor if there is a lot of potential for air movement around it like in a typical open attic situation. Plus it is more 'green' (I hate the buzzwords) ... as cellulose makes use of recycled newspaper ... that is simply a nice thing.
that's my couple of two cents
It will be blown in under existing t & g attic boards.
Jeff
enclosed, you will likely get good performance out of either choice (installed properly). I'd still lean toward the 'green' cellulose. It uses an otherwise largely wasted resource. That's just my personal general feeling ... not applied to your situation at all ... so you still have to make some judgement call for your particular situation.
Not sure what the R-value per inch is ... I suspect the cellulose may have an edge, but they are similar, I think ... cellulose should be 3.7 or 3.8 and FG may be 3.33-3.5 ... so in a confined space, I'd opt for the higher R per inch, also.
jeff.... i prefer the cells.. especially if it is cells made with borates
i've seen mice and other things living in fiberglass... never seen vermin living in cells Mike Hussein Smith Rhode Island : Design / Build / Repair / Restore
Thanks Mike, I knew you'd be along on this. And thanks for the borate reminder. Any particular manufacturer?
Jeff
all mine comes from National Fiber, Belchertown, MA.. but there are regional mfr's all over the place....
National's is called Cel-Pak, using 100% boric acid & boraxMike Hussein Smith Rhode Island : Design / Build / Repair / Restore
I think all cells are required to be borate treated.
Google up cellulose manufacturers association and find out who's local to you.
Joe H
no...... a lot of the less expensive cells are treated with ammonium sulphate and/or aluminum sulphate
some use a mix of borates and sulphates
i will only use 100% borate products
National used to make two products.... Thermo-Cel ( with sulphates ) and Cel-Pak with borates... now they only make Cel-PakMike Hussein Smith Rhode Island : Design / Build / Repair / Restore
The local Mountain Fiber is borate only.
Learned something new.
Cell association is http://www.cellulose.org/CIMA/SiteMap.php
Need to find a new source, moving south if I ever sell this place. :(
Joe H
Can you use a BIBBS membrane to blow in cellulose where the space isn't finished, or won't be finished until later?Jeff
Also, would FG be better in conditions where there may be voids that could get filled (coarser material)?Jeff
NO