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GBlist: Questions concerning wet-spray cellulose

Auntie Mike (and the rest of the list),

A couple of questions:
1)  How long does it take the wet-spray cellulose to dry under "normal" conditions?  (I'm
asking for a crude rule of thumb.)

2)  Re: vapor retarders will cellulose insulation, I've heard some (some what? you ask)
claim that no vapor retarder should be used *on the interior*.  This seems a bit strange.

3)  In the EEBA Builder Guide (cold climates) it states (and I'm paraphrasing from
memory because I don't have it in front of me) that semi-permeable and impermeable
rigid board insulation should not be used on the exterior when cellulose insulation is
used.  Is this to allow for drying/removal of moisture from the installation, or moisture
which presumably, inevitably, would find it's way into the wall even with a
well-constructed interior vapor retarder.

I've got a couple more questions about the Builder Guide, but I'll wait until I have it in
front of me (and everyone's read it).

>>> Mike O'Brien <obrien@hevanet.com> 04/22/97 02:39pm >>>
I wonder if the description of the masonry wall insulation in Home Energy
might have left out a couple of important details--so, just in case, allow
me to restate the obvious: the wet-spray insulation should dry out before
it is covered, so it doesn't end up growing mold. There should be a
continuous vapor retarder, such as clear poly sheet, installed over the
insulation. The drywall should be mudded or caulked to stop air leaks, at
penetrations like pipes, outlet boxes, air conditioners etc., and along the
bottom plates.

Auntie Mike
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