[GBlist] Re: greenbuilding Digest 25 Dec 2001 12:40:22 -0000 Issue 174

["Alan Abrams" <awabrams@starpower.net>]

thanks all for the informative discussion on
alternatives to wood trim.  It's no fun watching the
trim on houses I built 10-12 years ago beginning to
compost.  Any comment or advice on the structural
characteristics of the encapsulated fiber product--for
example, regarding the design of exterior railings?  By
comparison, Certainteed's Boardwalk system (which uses
PVC) is not very stiff; their design manual imposes
rigorous limits on spans and configurations.

Alan Abrams

>
> A deck product made by AERT (Advanced Environmental
Research Technologies)
> and distributed by Weyerhaeuser is called Choice-dek
((www.choicedek.com))
> When compared to Trex, I believe it beats it hands
down (although as of yet,
> they have no colors other than the weathered grey).
The reasoning for its
> superiority is that in addition to HDPE and LDPE
(high and low density
> polyethylene), it used Linear Low Density
Polyethylene.  This, to my
> knowledge enables all the wood fibers (it is made of
50% wood fiber, either
> Ash Juniper for Choice-dek, or Oak for Choice-dek
Plus) to be encapsulated
> by plastic, not just sit next to it.  So, it is
encapsulated, which helps
> with potential freeze-thaw issues.  Also, Trex is
water cooled when it comes
> out of the extruder, which tends to or can cause
plating (basically
> differential cooling which creates a layer structure
within the product).
> If you look at the cut piece of Trex, you will see
what I am talking about -
> a swirl around the center of the piece.
>
> So, where I was going, is that Choice-dek has trim
for decking which I have
> used for fasica.  It comes 1"x10" nominal in 12'
lengths, and is either
> primed (holds paint like Hardie - 12 years) or
natural (and will weather
> grey).    I think in order for Trex to hold paint,
other than just by
> surface tension, the material would have to fully
oxidize (couple months).
> The choice-dek can come already primed, and actually
will cost less than
> Trex, and carries double the warranty.
>
> back to the question at hand, AERT's main product is
composite window trim
> pieces that they have been selling for over a decade
to some of the window
> giants to encorporate in their design.  They have now
come out with a half
> plastic/half wood trim system that they call
Moisture-shield
> ((http://www.moistureshield.com/).  They have many
options, most of which
> tongue and grrove together.  I believe it is primed,
though have only seen
> samples.  It does look pretty slick, and if you have
window trim, sill, etc,
> that will never rot, needs painting only after a
decade span, and will be
> essentially maintenance free, why not.  Though it has
yet to be fully
> marketed, and likely is not available in many places
in the country, the
> MoistureShield should, I believe, prove to be a
winner.
>
> > Here is how we do exteriors:
> >
> > Hardiplank or Hardiboard w/battens in the field,
Hardiboard for soffits,
> and
> > Trex decking for trim. The facia is the 1 by 6
stock and the corner boards
> and
> > window/door trim are the 5/4 stock. Cutting
cementous material for the
> field is
> > annoying enough but the straight cuts are no big
deal. Try milling some
> details
> > in a piece of Harditrim, it is impossible. The Trex
goes through the
> planer
> > better than wood and takes a router without any
tear-out, any milling
> detail is
> > a breeze. Bends unlike any other material for
radius facia, etc.. We just
> make
> > sure we collect all of the chips and dust and
dispose of it properly. Trex
> takes
> > paint well also. We seldom use it for decking.
> >
> >



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