[GSBN] Vapor Barrier

[Robert Tom]

> Date: Thu, 17 Jul 2008 12:06:50 -0600
> From: Jeff Ruppert <jeff.ruppert at gmail.com>

> We are dealing with a picky building official and are interested in
> options to seal interior earthen plaster with a sealer that offers a low
> permeability and that is also non-toxic.  The building official is
> requiring the use of a vapor barrier on the interior and we are a little
> stumped as to what to use.  Code requires something with a perm rating
> of 1 or less.


AFM Safecoat makes a number of low VOC/no-VOC interior sealers, paints and  
finishes that would do the job but any low VOC coating with a high solids  
content would probably be just as effective.

There is no mention made of the earthen plaster thickness or density or  
what if any further plaster treatments will be applied so we don't know  
what the vapour permeance of the plaster itself might be at this point but  
increasing the plaster thickness and using a finishing method that would  
create a very dense surface (ie Tadelakt-like finish) would have a bearing  
on the permeance of the assembly.

=== * ===
Rob Tom
Kanata, Ontario, Canada
< A r c h i L o g i c  at chaffY a h o o  dot  c a >
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