GBlist: Request info on Dow Corning's FORMULAR rigid polystyrene insulation (any toxicity for indoor

Lawrence F. London, Jr. (
Mon, 10 Feb 1997 22:52:50 -0500 (EST)

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.

Does anyone know whether FORMULAR will outgas toxic fumes over the short
or long term? Will my containment system be adequate to prevent
infiltration of any possible toxics into my living space? As it will be
exposed to moderate heat due to proximity to the outer block wall warmed
by the woodstove I am wondering if this factor would result in the
stimulation or acceleration of outgassing.

If FORMULAR turns out to not be acceptable for this application does
anyone know of a rigid insulation that would be?

Many thanks for any advice or pointers to resources on this subject.

Some of you may find my renewable energy page interesting.

Lawrence London
Chapel Hill, N.C.

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