Timber Species Australian Oak

Eucalyptus regnans & delegatensis

Australian Oak

Also known as: Mountain Ash, Alpine Ash, Victorian Ash, Tasmanian Oak

Region of Origin: Australia
FlooringInterior JoineryMouldingsPanelling
Density
660 kg/m³
Durability
Moderately Durable
Janka
4.9 - 5.7 kN
Strength Group
SD4, SD6
Australian Oak timber grainTimber Grain

About this Timber

General Description

Australian Oak is a mixture of two Eucalypt species. It ranges in colour from pale pink to brown straw. It is straight, open and even grained with a uniform texture. Usually all quartersawn for stability. Has excellent staining properties.

Working Properties

How This Timber Works

Australian Oak is relatively easy to work and takes a good finish. It is also a good bending timber. Pre-boring advisable when nailing or screwing. Australian Oak takes glue well.

Mechanical Properties

Medium bending strength and stiffness properties, high crushing strength but poor steam bending classification.

Technical Data

Technical Specifications

Density
660kg/m³
Air dry density (avg)
Durability Class
Moderately Durable
Strength Group
SD4, SD6
Structural classification
Janka Hardness
4.9 - 5.7kN
Surface hardness rating
MOR — Modulus of Rupture
68
Unseasoned MPa
109
Seasoned MPa
MOE — Modulus of Elasticity
12.5
Unseasoned GPa
14.8
Seasoned GPa
Shrinkage — Green to 12% Moisture Content
9.0%
Tangential
5.0%
Radial
Dimensional change from green timber to 12% moisture content

*Air Dry Density (kg/m³) is an average indication only and actual values may vary. Refer to strength, shrinkage and durability classification tables for full details.

Reference Tables

Timber Classification Tables

Standard NZ classification tables for strength groupings, shrinkage and durability. This species is highlighted in each table.

Minimum Values for Strength Groups
Unseasoned Timber  |  Units: MPa = 145 lb/sq.inch
Strength Group Modulus of Rupture Modulus of Elasticity Max Crushing Strength
S1 103 16300 52
S2 76 14200 43
S3 73 12400 36
S4 62 10700 31
S5 52 9100 26
S6 43 7900 22
S7 36 6900 18
Minimum Values for Strength Groups
Seasoned Timber  |  Units: MPa = 145 lb/sq.inch
Strength Group Modulus of Rupture Modulus of Elasticity Max Crushing Strength
SD1 150 21500 80
SD2 130 18500 70
SD3 110 16000 61
SD4 94 14000 54
SD5 78 12500 47
SD6 65 10500 41
SD7 55 9100 36
SD8 45 7900 30
Shrinkage Classifications
Shrinkage from Green to Oven-dry (12% MC) – % before reconditioning
Description of Shrinkage Tangential Radial
Very Low0 – 3.50 – 2
Low3.5 – 5.02 – 3
Medium5.0 – 6.53 – 4
High6.5 – 8.04 – 5
Very High> 8.0> 5
Durability Classifications
Approximate service life (years)
Grade of Durability Fully Protected Above Ground, Exposed In-Ground, Exposed
Very Durable> 50> 40> 25
Durable> 5015 – 4015 – 25
Moderately Durable> 507 – 155 – 15
Non-Durable> 500 – 70 – 5
This species – Strength Group
SD4, SD6
Highlighted in the strength tables above
This species – Durability
Moderately Durable
Highlighted in the durability table above

Applications

Main Uses

Flooring Interior Joinery Mouldings Panelling

Stock & Sizes

Availability

Kiln-dried sawn 25mm, 40mm and 50mm thicknesses in varying fixed widths. T&G strip flooring and overlay profiles.

Quality Standard

Grading

Grade Prime