Timber Species: Tallowwood (Eucalyptus microcorys)

Physical Properties

Dry Density:  990 kg/m³

Janka Hardness: 8.6 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.

Tallowwood, Australian Hardwood Species used in Timber Flooring

Tallowwood, Australian Hardwood Species used in Timber Flooring

Tallowwood Species Description

Native and common to both Queensland and New South Wales, tallowwood is a tall evergreen, growing to around 40 meters and dependent on moderately fertile soil and high levels of direct sunlight. Tallowwood, despite its dependence on fertile soil and direct sunlight, has been known to thrive in mountainous and hilly and locations where it’s occasionally subjected to both excessive frost and drought.

Named for the greasy, oily feel of the wood when it’s cut, tallowwood has spongy, soft, orange-tinged rough bark and a dense crown of leaves. These leaves, which have traditionally been used to dye woolen and silken cloth, are a natural food source for koalas, and the sap of the tallowwood is highly sought-after by beekeepers for the distinctive flavor it lends to honey.

Tallowwood has naturally high occurring amounts of tannin in its timber, lending it a unique grain structure, beautiful growth rings, and a yellowish-brown hue with olive green notes throughout. It’s a relatively hardy timber with a Janka rating of 8.6 and a density of 990 kg/m³, making it robust and durable yet still workable, and as a result it’s a darling of architectural designers everywhere. Tallowwood is often used for solid timber flooring and decking, as its naturally high tannin count acts as a strong preservative against weathering despite its moderate hardness rating.

 

 

Australian Hardwood Timber Species | Tasmanian Oak

 Technical Properties of Tallowwood

Species Name

Tallowwood

Botanical Name

Eucalyptus microcorys

Colour Range

Brown

Janka (Hardness) Rating – Dry

8.6

Natural Durability Class

In-ground contact
Outside above ground contact

1

1

Density (kg/m³)

Unseasoned (Green)
Seasoned (Dry)

1230

990

Strength Group

Unseasoned (Green)
Seasoned (Dry)

S2

SD2


Joint Group

Unseasoned (Green)
Seasoned (Dry)

J1

JD1

Fire Indices

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

5

4

>2.2 to <4.5

<750

3

UNKNOWN

Tangential Shrinkage %

6.1

Toughness (Nm)

Naturally Unseasoned (Green)
Seasoned (Dried)

20

 17

Naturally Termite Resistant to AS3660

RESISTANT

Naturally Lyctus Susceptible

 SUSCEPTIBLE

 

Summary
Tallowwood. Hardwood Species Specification Data
Article Name
Tallowwood. Hardwood Species Specification Data
Description
Timber Species: Tallowwood (Eucalyptus microcorys) Physical Properties Dry Density: 990 kg/m³ Janka Hardness: 8.6 kN
Author
Publisher Name
Better Timber Flooring
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