Ash, Crow’s | Flindersia australis

Crow’s ash is a large hardwood species that is native to northern NSW and parts of Queensland. It is used mainly for flooring, boat building and outdoor furniture.

Other Names: Australian Teak, Flindosy, Nutwood, Colonial Tea

Overview

Crow’s ash, also known as Australian teak, is a large hardwood species native to parts of northern New South Wales and Queensland. It grows in the coastal rainforests from northern News South Wales to Gladstone in Queensland and can reach up to 40m in height.

Crow’s ash is slow to dry and surface checking may occur if it is dried too quickly. Its heartwood is golden yellow with a more distinct, paler sapwood. Aside from appearance, Crow’s ash main benefit is that it is a very strong timber.

Crow’s ash is predominately used for flooring and decking. It is also used for boat building and outdoor furniture. In times gone by it was used as flooring for dance halls due to its highly durable characteristics.

While it is visually appealing, this species is not easy to work with, which limits the applications it can be used for. Crow’s ash is quite greasy which means it is hard to glue and nail.

Due to its limited availability, Crow’s ash timber may attract a premium.

 

Properties

Shrinkage

Very Low Low Medium High Very High
Tangential:          
4.2
Radial: 2 - 3

Strength Group

Very High High Reasonably High Medium High Medium Reasonably Low Low Very Low
Unseasoned:S1S2S3S4S5S6S7
Seasoned:SD1SD2SD3SD4SD5SD6SD7SD8

Stress Grade

Structural
No. 1
Structural
No. 2
Structural
No. 3
Structural
No. 4
Structural
No. 5
Unseasoned: F27 F17 F14 F11 F8
Seasoned: F27 F22 F17 F14 F11

Density per Standard

Unseasoned: 1050 kg/m3
Seasoned: 940 kg/m3

Joint Group

Very High High Reasonably High Medium Low Very Low
Unseasoned:J1J2J3J4J5J6
Seasoned:JD1JD2JD3JD4JD5JD6

Colour

  White, yellow, pale straw to light brown Pink to pink brown Light to dark red Brown, chocolate, mottled or streaky
   

Mechanical Properties

Modulus of Rupture - Unseasoned: 105
Modulus of Rupture - Seasoned: 135
Modulus of Elasticity - Unseasoned: 14
Modulus of Elasticity - Seasoned: 17
Maximum Crushing Strength - Unseasoned: 54
Maximum Crushing Strength - Seasoned: 70
Impact - Unseasoned: 23
Impact - Seasoned: 17
Toughness - Unseasoned: Medium - 15 - 25 Nm
Toughness - Seasoned: Medium - 15 - 25 Nm
Hardness - Unseasoned: 8.5
Hardness - Seasoned: 11

Durability

Low Moderate Reasonably High High
(0 - 5 yrs) (5 - 15 yrs) (15 - 25 yrs) (more than 25 yrs)
In-Ground:
(0 - 7 yrs) (7 - 15 yrs) (15 - 40 yrs) (More than 40 yrs)
Above ground:
(0 - 20 yrs, usually < 5) (21 - 40 yrs) (41 - 64 yrs) (More than 60 yrs)
Marine Borer Resistance:
Lyctid Borer Susceptibility: Susceptible
Termite Resistance: Resistant

Fire Properties

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
EFH Ignitibility:
0 1 2 3 4 5 6 7 8 9 10
EFH Spread-of-Flame Index:
EFH Smoke-Developed Index:
1 - non-combustible 2 - reasonably non-combustible 3 - slightly combustible 4 - combustible
Fire Properties Group
Number:
Group Number - Other: 3 if used on MDF or particleboard ≥12mm; veneer thickness 0.6 - 0.85mm
Average Specific Extinction Area: <250
Bushfire Resistance: Bushfire Attack Level (BAL) 12.5 and 19 – All AS 3959 required applications  

Description

Botanical Name: Flindersia australis
Preferred Common Name: Ash, Crow’s
Other Names: Australian Teak, Flindosy, Nutwood, Colonial Tea
Species Type: Hardwood

Appearance

The heartwood of Crow’s ash is a rich golden yellow, with the sapwood distinctively paler and around 25-40mm wide. It has a medium and even texture and the appearance of the grain is often interlocked. Crow’s ash has a very greasy surface due to the occurrence of natural oils.

Common Applications

Crow’s ash is a highly durable timber, but due to its poor workability it is limited to certain applications. It is mainly used for flooring and decking, where its rich golden colour can be admired. Many old dance halls in Australia used Crow’s ash flooring, with many still in fantastic condition — a testament to the toughness of this species. Crow’s ash is also used for boat building and outdoor furniture.

Common Form

Sawn

Workability

Crow’s ash has a poor workability in part due to its greasy surface. It is hard to glue and its nail holding ability is poor and may also split along the grain if nailed. It will provide fair results for steam bending. One of the main benefits of using Crow’s ash is that is a very hard-wearing timber.

Origin of Timber

NSW, QLD

Availability - Further Information

Crow’s Ash is generally only available in the areas that it grows - the coastal rainforest areas of northern New South Wales and Queensland. It is has become one of the rarer Australian hardwoods and so it may attract a premium.

Source of Timber

Native Forest

Applications

  • Decking

    Timber decking creates spaces that are functional, practical and aesthetically pleasing. With the right design and care a timber deck will make a valuable addition to any home or business, creating an outdoor living space that will be enjoyed for years to come.

  • Flooring

    Whether for structural or finished flooring applications, timber offers durability, versatility and adaptability. The warmth, strength and natural beauty of timber flooring has proved enduringly popular in a wide variety of interior settings.

  • Pergolas

    A timber pergola is a practical, functional and attractive way to extend living and entertainment spaces into the outdoors.

  • Timber Joinery Products

    Timber joinery products offer a classic, unique and stylish touch to any interior design.

Case Studies

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