Wood Species

Name	Wood	Janka Rating
Karri		2030

Karri
Eucalyptus diversicolor

Origin: Western Australia and South Africa

Appearance:

The sapwood of karri is whitish while the heartwood is pale pink to a reddish brown in color. The species has an interlocked grain and is moderately coarse in texture.

Resistance, Durability:

Karri has a natural resistance to decaying. The wood is reported to no discernable odor. Karri is very difficult to dry properly due to its tendency to check or warp when the process is rushed. This particular species has a propensity to move over time with changes in temperature and humidity, and as such should be used in areas with a stable climate.

Janka Hardness: 2030

As a flooring choice, karri is a very hard and durable wood. It is forty percent harder than hard maple, and a little bit more than fifty-seven percent harder than red oak, is just over ninety-two percent as hard as santos mahogany's ranking of 2200, and is just over eighty-six percent as hard as Brazilian cherry.

Workability:

Karri can dull cutting tools rather easily and as such can pose some difficulty when sawing. Nail installation requires holes to be pre-bored beforehand. Glue holds somewhat well with karri flooring. This wood requires some effort to sand properly but yields a good polish.

Main Uses:

Karri's uses include flooring, framing, shipbuilding, plywood, and joinery.

What is a Janka Rating?

"It is one of the best measures of the ability of a wood species to withstand denting and wear. It is also a good indicator of how hard a species is to saw or nail.

The hardness of wood usually varies with the direction of the wood grain.

A common use of Janka hardness ratings is to determine whether a species is suitable for use as flooring."

Colored Bamboo

Some species have different janka ratings depending on how they have been treated.

Bamboo is one example of this. If left with a natural finish, Bamboo falls at 1380 on the hardness scale. If you carbonize it to get a darker color, the rank falls to 1180.