Jarrah Hardwood Timber Species Specification Data

Timber Species: Jarrah (Eucalyptus marinata)

Description:

JarrahProducing a dense, hard-wearing but easy to work with timber, the jarrah is practically everywhere in the southwestern reaches of Western Australia. With stringy bark that sheds in long, vertical strips and an average maximum height of some 40 meters, the jarrah is famous for providing homes to wild animals and insects, particularly bees. In fact, jarrah honey is some of the darkest, thickest, and most flavourful on the market.

Yet despite its utility as animal habitat both alive and dead, this rare commercial tree from Western Australia produces timber with a beautiful, rich red colour that matures naturally into a deep, soft burgundy that provides a touch of class and warmth to any room. Its density of 820 kg/m³ and hardness of 8.5 on the Janka scale provide for durable flooring that’s resilient enough to be used not just as solid timbers but as engineered flooring, parquetry, or decking, and its natural insect resistance is  highly sought after as a building material in both residential and commercial settings.

In addition to flooring, jarrah is a popular timber for cabinetry and paneling, and its durability makes it ideal for outdoor furniture as well. It’s so durable that it’s nearly impossible to work it once it’s been seasoned, so most woodworkers prefer using it as a building or construction material while it’s still green and before it has a chance to dry out and harden. It’s so robust that it was once exported to the United Kingdom for road construction, and today there’s a booming industry in reclaiming this handsome, burgundy wood from houses due for demolition in order to repurpose and recycle it into new construction and dwellings.

Physical Properties

Dry Density:  820 kg/m³

Janka Hardness: 8.5 kN

These properties are only a guide, as timber is a natural product there will be variations within any species. The Janka Dry Hardness rating measures the hardness of the wood. The higher the number the harder the wood.

 

Technical Properties of Jarrah

Species Name

Jarrah

Botanical Name

Botanical Name

Eucalyptus marginata


Colour Range

Red

Janka Hardness

Janka (Hardness) Rating - Dry

8.5

Natural Durability
Natural Durability Class

In-ground contact
Outside above ground contact

-

2

2

Timber Density
Density (kg/m3)

Unseasoned (Green)
Seasoned (Dry)

-
1170
820

Strength Group

Strength Group

Unseasoned (Green)
Seasoned (Dry)

-
S4
SD4

Joint Group
Joint Group

Unseasoned (Green)
Seasoned (Dry)

-
J2
JD2

Fire Indices
Fire Indices

Spread-of-Flame Index
Smoke-Developed Index
Critical Radiant Flux
Smoke Development Rate
Group Number
Naturally bushfire-resisting Timber

-
3
3
>2.2 and <4.5
<750
3
Unknown

Tangential Shrikage
Tangential Shrinkage %

7.4

Timber Toughness

Toughness (Nm)

Naturally Unseasoned(Green)
Seasoned (Dried)

-

13

10

Termite Resistant

Naturally Termite Resistant to AS3660

R = Resistant
NR = Non resistant

RESISTANT

Lyctu Susceptible

Naturally Lyctus Susceptible

S = Susceptible
NS = Non susceptible

 SUSCEPTIBLE

 Australian Hardwood Timber Species | Messmate