Greetings...
I have had problems
posting to the list, so I will reply to you who were interested.
I have seen some of
these houses, have a cd full of pictures, and have talked a lot to
some of the people involved. It seems that the problems are a result of several
factors, not the least of which involves following the manufacturer's specs.
Several of these homes with failed roofs were done by their respective
manufacturer in training local builders on how to use their product. Others were
homes owned and lived in by the builders or their manufacturer reps. So I think
it is not strictly an installation issue. Most of the manufacturers have said
that no vapor retarder is needed. BZZZZZT! In a cold climate with a 40-50 degree
delta T and high humidity levels, the latex condom idea is only safe practice.
BTW... many of these
homes have HRV's that are in good working order and are
used.
If SIPS are to be used
in wet, cold, climates, manufacturers instructions must be exceeded. A vapor
retarder is required. All seems need to be sealed. Foams with longer cure
times must be used for spline sealing. The cost for replacing these roofs
is huge, $60 to 120K per house, and we have over 120 homes with these problems
noted. Insurers are backing off paying for claims, and the manufacturers are
running. Not a great situation, particularly for the homeowners and builders who
were promised this technology would work.
Just my
$.02
Scott Waterman, Energy
programs coordinator, Alaska Housing Finance Corp.
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Date: Tue, 26 Feb 2002 11:53:38 -0600
To: GB List <greenbuilding@crest.org>
From: Chris Koehn <chris@koehn.com>
Subject: re: SIP roofs rot in wet climates
Message-ID: <B8A127C1.35DB%chris@koehn.com>
Scott-
I don't think the article really said that SIP roofs are
generally a bad
idea in wet climates. I've read the SIPA (structural
insulated panel assoc.)
report, and while I think there's still a fair amount not
known, it seems
that poor installation, poor treatment of penetrations,
poor- or
non-existent- sealing at the panel joints, poor vapor
barrier treatments,
and (probably most importantly) poor
ventilation/dehumidification detailing
significantly contributed to the problems.
I think that SIPs may be particularly sensitive to proper
installation and
ventilation in extreme conditions, but to say that SIPs
don't work in damp
climates as- as of yet- not accurate.
Chris
------------------------------
, Scott Schreffler wrote:
>January issue of the Journal of Light Construction had
an article citing
>houses in Juneau Alaska (very wet climate) with
3-year-old rotting SIP
>roofs. The article claimed that it was partly due to
faulty installation,
>but that SIP roofs are inherently a bad idea for wet
climates.
>Does anyone have any experience/insight into
this?
>Scott Schreffler
>BUMGARDNER
>Architecture Interiors Planning
>Seattle, Washington
____________________________________________________________________
Scott,
Don't you like mushrooms growing out of the roof
:-)
I'm not a building specialist, even not a SIP-lover, but
when you read
amongst others:
http://www.jlc-update.com/archive/12_01/panel_roof.html
and surely this 5 Perspectives/viewpoints at :
http://www.sipweb.com/monitor/monitor_feature.asp
Since there were more than 5 different manufacturers it is
not a problem of
a specific mark of SIP's that is not good.
And since SIP's are already used for more than 3
decades
( and also in damp climates ), the problem is
elsewere.
Than one looks more in the direction of correct sealing of
the joints, correct
placing of the vapor retarder without openings in
it;
and correct assembling, and in such a damp climate a very
good ventilation
(with heat recovery), to prevent condensation is of
primordial importance,
for any closed construction in cold climate and shurely with
organic
building materials.
Moving to nevada or texas also prevent the problem
:-)
My 2cents
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Reply's to BrunoM1@yucom.be
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