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Selangan Batu, Yellow Balau,
Balau,
Bangkirai, Alan
Shorea spp.(
heavy hardwoods)
There are many different subspecies
of Shorea grouped here, the most common being: albida, glauca, laevifolia and laevis. These
species are very common throughout Malaysia
and Indonesia with some
in the Philippines,
all being large hardwoods growing within a range of 30 to 60 metres high.
The timber is dense but contains
little silica and is therefore relatively easy to work although some
adjustment to saws and
machine knives may be required on long runs if a good surface finish is
required. The timber of all species are very similar with the heartwood
yellow brown, reddish brown and sometimes purplish brown and will darken
with age.
The sapwood is usually very
distinct being much lighter usually pale yellow.
The texture is fine to medium and
even with the grain wavy and interlocked. Shrinkage rates are medium to low
and all species are considered to be lyctid borer
susceptible.
Balau has been widely used in South East Asia as a heavy construction timber as
well as window joinery, boat building, beer and wine casks and in some
cases veneer.
In Australia the timber has been
regularly used for domestic decking and flooring, stair manufacture and
window and door sills.
Note: Another group of Shorea spp. called Red Balau are sometimes offered as an alternative, these
timber are slightly lighter in Density and of lower durability and should
therefore be avoided for exposed external applications. Heartwood is
usually a deep red-brown with the sapwood much lighter and easy to
distinguish.
Timber Properties
Density (average)
1000 kg m3 green
900 kg m3 dry
Durability: Class 2
Strength Group
S2 green
SD3 dry
Hardness Rating (average)
(Provisional)
8.0 kN
green
9.0 kN dry
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