Re: GBlist: Natural sealants

Hal Levin (hlevin@cruzio.com)
Fri, 21 Feb 1997 10:25:49 -0800

At 10:06 AM 2/21/97 -0500, John B. wrote:
> Marc
[snip]
> Polyurethanes (caulks and other construction products) have been known
> to emit certain types of gasses (I think MDI is one) which are claimed
> to be harmful, so even though they perform really well, I'd avoid
> them. Silicones, I believe, are less "emitting", but I don't have the
> facts on that. I would come down in favor of siliconized acrylic
> latex, which is fairly odorless and has a little bit of flexibility
> (so its not great in joints that move a lot). Its mostly acrylic, I
> believe, and is readily available and paintable.
>
What are caulks used for in joints that move? Aren't Marc's movement
concerns about thermal expansion?

> In a new construction project, it would be somewhat easier to build in
> such a way as to minimize the need for caulk-in an old building, that
> option is pretty much shut out. I think a better, tighter home where
> acrylic caulk is used is the more sustainable option versus a leaky
> home with none.

What is the basis for the notion that one is "more sustainable" than the
other? I would like to know your criteria and the data you use to evaluate
the alternatives against those criteria.

.
Hal Levin <hlevin@cruzio.com>

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