[Greenbuilding] [BULK] Re: Cellulose settling

[John Messerschmidt]

I have to agree.  I chose Icynene on our house over cellulose.  It's
airtight, and an easy, fast installation.  No ridge vents were required, so
it took a discussion with the town's building inspector, but 20 minutes
before they got there he signed off on it.  I was there when they sprayed it
on, it's pretty cool, and fun to watch.

It's not recycled, but you can't have everything.  Also, the foam expands
past the studs so they saw it off to be flush for the sheetrock.  They
haven't figured out what to do with this left over spent foam yet.  Maybe
someone has a suggestion for that.

I've heard that Tiger Foam has a much higher R value and will try that out
next time I have a chance.  You have to spray that on yourself, though.

John



-----Original Message-----
From: greenbuilding-bounces at listserv.repp.org
[mailto:greenbuilding-bounces at listserv.repp.org]On Behalf Of Jill
Edelman
Sent: Friday, July 28, 2006 10:17 AM
To: geoedb at idiom.com; greenbuilding at listserv.repp.org
Subject: Re: [Greenbuilding] [BULK] Re: Cellulose settling


Hi all,

  I've been following this thread, and I'm puzzled:  Why has no one
suggested low density, open cell foam-in polyurethane eg Icynene?
Granted, it doesn't have the recycled material content of
cellulose, but it's stability over the temperature range and air
sealing qualities have made it really attractive to me and my
office colleagues.  Icynene has a pour-in formulation for closed
walls.  Here's what EBN has to say about Icynene:

  Icynene is a low-density, open-cell modified polyurethane that is
typically foamed into open cavities. The product has a very high
(100-fold) expansion rate, so installation involves spraying on a
very thin layer—much like spray painting. Within seconds, the foam
expands to its full thickness, filling (and often overfilling) the
cavity. The cured foam has a density of about 0.5 lb/ft 3 (8 kg/m
3) and an R-value of 3.6 per inch (RSI/m-25).

  About two years ago, Icynene introduced a slightly different
formulation for use in closed cavities. In this formulation, the
Icynene is poured into the cavity and expands from bottom to top to
fill the cavity. The company recommends two pours: one to fill the
cavity about 90% full, then a smaller amount of foam to top it off.
The cavity-fill product has a slightly greater density and an
insulating value of R-4/inch (RSI/m-28).

  From an environmental standpoint, there are several advantages to
Icynene. First and foremost is the absence of any ozone-depleting
chemicals. Water serves as the foaming agent, reacting with the
other components to generate CO 2, which expands the foam. (The
switch by conventional polyurethane manufacturers from CFC-11 to
HCFC-141b has greatly reduced the ozone-depletion impacts, but even
the HCFC depletes ozone to some extent.)