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Advertising supplement provided Jeld-Wen
Windows & Doors
A search for a more effective solution
with lessened environmental impact has led an Oregon manufacturer
to a new process that 1) treats wood under pressure and using
vacuum techniques—allowing nearly complete saturation
(most processes rely on a surface coat to repel moisture and
insects) and 2) uses a relatively new chemical formulation
in place of solutions common to the industry.
The pioneering venture, in concert with
a chemical company specializing in wood-treating systems,
replaces the “dip” common to the industry. Preliminary
test data, says the manufacturer, suggests the process is
highly effective. In addition, full-penetration treatment
reduces the possibility that the “envelope of protection”
afforded by the treatment will be broken in assembling and
installing the woodwork, says a manufacturer’s representative.
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| Left: Three unpainted
L-joints in our greenhouse after 29 months exposure.
The middle one is treated with the new process (machined
from treated stock), with an untreated to the left
(one of 3 of 10 that had not already failed), and
on the right (fungus growing our) is a IPBC dip
treated L-joint. Right: L-joints and window units
in Hilo. |
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Treated wood typically has eight times
the useful lifespan of untreated wood, according to calculations
by the American Wood Preservers’ Institute (AWPI).
Most of us are familiar with the most
common forms of wood treatment: creosote, the black or brownish
oil made by distilling coal tar is widely evident as the preservative
for railroad ties and, frequently, utility poles. Contemporary
outdoor construction nearly always is done with pressure-treated
lumber characterized by a green cast and the incisor marks
of the treatment process.
We are most likely, however, unfamiliar
with less apparent forms of treatment. It may be surprising
to some to find that most millwork used in wood windows are
subject to some form of preservation technique.
Globally, wood preservation is a $10
billion industry and is a science of intense interest worldwide.
A “Google” web search of the subject results in
a half-million hits. Annual North American production of treated
lumber is estimated to be in the range of 6-to-7 billion board
feet.
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