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a Fast Facts on HRA finger-jointed lumber
WWPA finger-jointed lumber mills will
soon be changing grademarks to meet new requirements established
by the American Lumber Standard Committee,
Inc. (ALSC) for lumber joined with heat-resistant adhesives.
Under the new requirements, finger-jointed
lumber joined with qualified heat-resistant adhesives will be marked
with the designation HRA (Heat-Resistant Adhesive). The HRA mark,
which will be incorporated into the gradestamp, indicates the lumber
is suitable for wood frame assemblies where a fire rating is required.
U.S. building codes require fire-rated
assemblies in multistory/multifamily structures between living units
or common party walls in commercial buildings. Detached single-family
houses under current codes do not require one-hour fire-rated assemblies.
Finger-jointed lumber made with adhesives
that are not heat resistant will be marked as Non-HRA. WWPA mills
are expected to add the new marks to all finger-jointed lumber in
the coming months. Finger-jointed lumber without the HRA and
Non-HRA marks are assumed to be not suitable for use where a fire
rating is required.
The new labeling system was established
following fire tests conducted by Forintek Canada and the American
Forest & Paper Association's American
Wood Council.
In late December 2006, the American Wood Council informed the International
Code Council (ICC) about the fire tests. The ICC sent a notice
in January to building code officials throughout the country and
a number of jurisdictions began to ban the use of finger-jointed
lumber.
WWPA was instrumental in developing the
new labeling system, which was accepted by the ALSC Enforcement
Subcommittee in early February. ALSC formally approved the HRA and
Non-HRA labels on Feb. 23, 2007. The ALSC labeling requirements
reference an American Wood Council test protocol which has been
adopted to qualify adhesives as heat resistant.
WWPA has developed product support materials
to help mills explain the new HRA labels on finger-jointed lumber
and the appropriate uses for such products. The Fast Facts entitled
"Heat-Resistant Adhesives (HRA)
and Finger-Jointed Lumber" show the new HRA and Non-HRA
marks on gradestamps for finger-jointed lumber and explains how
these products should be used in construction.
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