On June 9th, 1981, the Fire Laboratories Division of Warnock Hersey Professional
Services Limited conducted a fire endurance and hose stream test on the IHC 5x8 laminated
cedar timber wall system. Testing was conducted in accordance with the Uniform Building
Code 43-1.
Description:
The test wall was constructed to a height of 10 foot 3 inches and 10 foot 11 inches wide,
approximately 100 square foot of this wall was subjected to the fire endurance test
program.
Installation:
The cedar wall assembly was constructed and installed into Warnock Hersey's test
structure by personnel representing International Homes of Cedar. The wall was
constructed with 3M Scotch- Grip 5230 adhesive run along the upper surface of each
succeeding layer of timbers and applied in a five bead pattern. The test wall was
constructed with two short "stub" walls used to stabilize the longer wall and simulate
interim room partitions.
The Fire Test:
The movable wall containing the test assembly was secured to the furnace and the pilot
burners were ignited. The two lower main burners and two auxiliary upper burners were
fired and timing begun immediately upon achieving maximum high fire. A load of 1400
lbs. per linear foot was applied to the test assembly throughout the fire endurance test and
increased to 2000 lbs. prior to the hose stream test. During the test of one hour the
unexposed or interior face never exceeded 93 degress F, while 1600 degrees F was
maintained to the exterior or exposed face of the wall system. The temperature was
monitored by twelve thermocouples inside the chamber and recorded every I5 minutes
throughout the test of one hour. Deflection of the wall was measured every 15 minutes as
well.
Hose Stream Test:
Immediately following the fire endurance test, the moveable test wall was uncoupled from
the furnace and positioned for the Standard Hose Stream Test on the fire exposed face
while the loading was increased to 2,000 lbs per linear foot. The hose stream application
was bugun at the middle of the wall system and moved to the upper edge and slowly over
the entire surface in a zig zag pattern at a rate of 30 psi as measured at the base of the water
nozzle.
Observations:
No change in the wall system was noted during the load test while in the fire chamber, no
smoke leakeage was noted to the interior of the wall. Upon completion of the Fire Test the
entire exterior of the wall was burned uniformly but still no deflection of the wall system
was noted. The assembly looked extremely good through the hose stream test with no
through openings developing and no passage of water was noted through the wall system.
The load was decreased somewhat from 2,000 lbs and then increased to 2,100 lbs/ linear
foot. The wall maintained its shape, which now was 1.5 times the initial 1400 lbs. per
linear foot. The wall system load was further increased to 3000 lbs. linear foot before any
warping of the wall started and almost maintained the load. Because the overloading was
conducted after the full one hour rating period, and not one-half the rating period as
permitted in the standard, we conclude that this assembly would easily support 2,000
lbs/linear foot and would support 3000 lbs/ linear foot if tested for the 1/2 the rating period
as required by the standard.
Conclusions:
The 5x8 double tongue and groove cedar wall complies with the test standard, Uniform
Building Code 43-1 for a one hour rating. This wall system is eligible for listing and
labeling under the factory inspection program of Warnock Hersey Professional Services
Limited when applied for by, International Homes of Cedar, Inc.