From: loren@cstone.net (Loren Abraham)
It is almost a certainty that ALL foamed insulation products outgas a
variety of organic compounds. In my opinion the compounds which are
outgassed by styrene products ar less offensive (and less harmful) than
polyisocyanurates. mid (methyl isocyanurate) which is the catalyst is a
close relative relative of mic (methyl isocyanate) of Bhopal fame and
although less unstable is still very toxic and easily absorbed through th
skin. It is not safe to handle poly isocyanurates until totally
*cross-linked*. Other things can be outgassed as well. I would really
like
to hear Hal Levin comment on the relative safety of polystyrene and poly
isocyanurate foam board. In any case PLEASE do not mess with foamed in
place poly-iso insulation products. These chemicals should never be taken
out of a carefully controlled manufacturing environment and in my opinion
are not safe in any environment. The idea of adding normal casein glue to
blown in cellulose sounds rather nifty to me. Hal?
John Bunzick wrote:
----------
>
> I don't know whether foamed polystyrene outgasses, though I have not
> heard of this problem. I disagree with the reply comment about it
> loosing its blowing agent in 6 months. This foam is closed-cell, and
> it looses its blowing agent much more slowly than the
> polyisocyanurates, which have permeable cell-wall membranes. They do
> loose their blowing agent in 6 - 12 months. This process occurs
> progressively more slowly as air replaces the blowing agent, thereby
> lowering its insulation value. Polystyrenes are not known to loose as
> much R-value, though they don't claim as high an R-value to start
> with. The end result is that both types, polystyrene and
> polyisocyanurate, end up with similar R-values over time. The
> polystyrene is also less water absorbent.
>
> To clarify brand names, Dow Chemical Company (not Dow Corning) makes
> Styrofoam; UC Industries makes Foamular (with an 'a', not Formular
> with an 'r') though I believe they have been sold but can't remember
> to whom; and Amoco makes a foamed styrene called Amofoam.
>
> I am wondering though, why you plan to use the higher density
> material. The higher density material will cost you more, but it
> has the same R-value per inch. The higher density is intended for
> use in deck insulation situations where there are compressive
> loads on it.
>
> John Bunzick, CCS, CCCA
> Dean Architectural Alliance (new name)
> jbunzick@dprarchitects.com
>
>
> ______________________________ Reply Separator
_________________________________
> Subject: GBlist: Request info on Dow Corning's FORMULAR rigid polysty
> Author: "Lawrence F. London; Jr." <london@sunsite.unc.edu> at Internet
> Date: 2/10/97 10:52 PM
>
>
>
> I need to insulate the interior surface of a concrete block wall in
> my house with Dow Cornings's FORMULAR rigid high density insulation
> (FORMULAR 600, which has the highest density/PSI rating). This is in
> my living space in a room heated with a woodstove. I plan to construct a
> cavity wall to cover this insulation and to provide thermal mass, i.e. the
> insulation will be sandwiched between two block walls and sealed
> against contact with room air with cement and caulking as necessary.
> __________________________________________________________________
> This greenbuilding dialogue is sponsored by Oikos (www.oikos.com)
> and Environmental Building News (www.ebuild.com). For instructions
> send e-mail to greenbuilding-request@crest.org.
> __________________________________________________________________
-----------------------------------------------------------------------
Bruce Sullivan Tel: 541-484-9353
Iris Communications, Inc. Fax: 541-484-1645
Web: http://oikos.com/ E-mail: iris@oikos.com
------------ 1,700 green building product listings online -------------
__________________________________________________________________
This greenbuilding dialogue is sponsored by Oikos (www.oikos.com)
and Environmental Building News (www.ebuild.com). For instructions
send e-mail to greenbuilding-request@crest.org.
__________________________________________________________________