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Clear & Edge
Grain Douglas fir
Quotation are good for
30 days F.O.B Premium Quality Port Kells, BC
Canada
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More about Douglas Fir
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In the West, timber for products
is managed primarily in natural stands, on long
rotations. There are approximately 34.6 million Acres of
Douglas Fir managed primarily in natural stands.
Although production is much greater in Douglas Fir, the
two species account for more than 45 percent of all
Western softwood produced annually. Each year, more than
1.5 billion tree seedlings are planted in the U.S.
and billions more in Canada -- some five
new trees for each American. Nationally, annual forest
growth has continually exceeded harvest since the 1940,s.
In the West, forest growth exceeds harvest by 35 percent
or more each year with similar practices in
Canada.
Douglas Fir lumber products are
identified by region. Products from trees growing west
of the Cascade Crest to the Pacific Ocean, the most abundant region for Douglas Fir, are
simply identified as "DF" on the grade stamp. East of
the Cascades, Western Larch grows intermixed with Douglas Fir.
The two species are often kept separate in appearance grade
products but are combined in Dimension products and
marketed as "DF-L". Because Douglas Fir and Western Larch
share nearly identical structural characteristics and physical working
properties, the two species are interchangeable in Dimension
products. Douglas Fir grown in Canada is identified as
Douglas Fir North or "D
Fir (N)" as shown on the grade
stamp "DFN"
Premium Quality Diistribution
Ltd use's the following gradestamped National
Grade Rule (NGR) Dimension lumber this is recognized
by the Japanese Ministry of Land, Infrastructure and
Transportation (formerly Ministry of Construction) for
use in wood-frame construction.
Moisture content
As wood loses or gains moisture, it will shrink or
swell until it reaches equilibrium with the constantly
changing level of moisture in the air of its immediate
environment. All lumber benefits from some degree of
"seasoning," i.e. letting it adjust to the humidity
conditions of its surrounding atmosphere before it is
installed. Because of its cell structure, wood shrinks
primarily in width and thickness and very little in
length.
Douglas Fir is unique among all softwood species in
that it is naturally dimensionally stable, having the
ability to season well in position. Many builders prefer
to cut, nail and fasten Douglas Fir in the "green" or
unseasoned condition, allowing it to air dry during
construction. As a result, coastal Douglas Fir
structural lumber is often shipped unseasoned (indicated
by S-GRN on the grade stamp). Framing lumber 2 inches
and less (nominal size) in thickness can be shipped
after seasoning to a moisture content of 19 percent or
less, which is indicated by S-DRY, KD or KD-HT on the
grade stamp. S-DRY can mean kiln dried or air seasoned,
while KD and KD-HT specifically mean kiln dried.
Regional market conditions and building trade
preferences dictate local availability of dry or green
products.
For millwork, remanufacturing applications or glued
products, Douglas Fir is dried in temperature and
humidity-controlled kilns or stacked and air dried until
its moisture content (MC) reaches the desired level for
an intended purpose.
The term "DRY" can be confusing in lumber
terminology. In structural grades, "DRY" indicates a
product was either kiln- or air-dried to a 19 percent or
less moisture content level prior to surfacing. However,
in appearance products (e.g. the FINISH and SELECT
grades), "DRY" is defined in the Western Lumber
Grading Rules as being a maximum of 15 percent MC
and in these grades, 85 percent of the items will be
shipped with a MC level of 12 percent or
less.
Grading
Premium Quality's grade stamp assures conformance of
the graded piece with its applicable and in accordance of
the Western Lumber Grading Rules, and also to the
West Coast Lumber Inspection Bureau's (WCLIB) West
Coast Lumber Standard Grading Rules, the Pacific
Lumber Inspection Bureau's Export R List Rules, the National Lumber Grading
Authority's (NLGA)
Standard Grading Rules for
Canadian Lumber , the
Redwood Inspection Service's (RIS) Standard
Specifications for Grades of California Lumber and
the Southern Pine Inspection Bureau's (SPIB) NGR and
Scaffold Plank portion of the Standard Grading Rules
for Southern Pine Lumber . These rules provide lumber users with
a dependable measure for determining the quality and
uniformity of lumber as well as its performance
capabilities. e-mail Premium Quality for more
information sales@premiumquality.net
