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Vertically laminated timber
Vertically laminated timber is designed to resist bending loads applied parallel to the wide face of the laminations. For vertical loads, this means that the wide face runs vertically.

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Jarrah | Eucalyptus marginata

Jarrah timbers reflect the hues of the Western Australian landscape. The heartwood varies in colour from rich reds to browns, while sapwood ranges from a pale yellow to orange

Jarrah – reflecting the hues of the Western Australian landscape.

Jarrah is an Australian hardwood renowned for its versatility, durability and strength in a wide range of interior and exterior applications.

Overview
Properties
Description
Applications
Case Studies
Suppliers

Overview

Jarrah is a unique Australian hardwood renowned for its versatility. Its durability and strength make it an ideal timber for a range of structural and design applications, with timbers that display colours ranging from deep red to blonde.

Jarrah trees grow on the iron and aluminium rich plains of south-western corner of Western Australia, from the ranges east of Perth down to Albany. They are slow growing, their roots often reaching to great depths in search of nutrients and water. Their long, straight trunks, can grow up to 40 metres tall and 2 metres in diameter, creating beautifully coloured and grained timbers. The bark is rough with a fibrous texture, and covers the entire trunk and smallest branches. The trees do not germinate from seed, but from lignatubers, large underground swellings that store energy and nutrients, allowing young trees to regenerate after bushfires.

Jarrah timbers reflect the hues of the Western Australian landscape. The heartwood varies in colour from rich reds to browns, while sapwood ranges from a pale yellow to orange. The texture of the timber is moderately coarse and even-textured grain, although some interlocked, wavy grain may feature, creating interesting fiddle-back figure. This makes it an appealing architectural and design material.

Jarrah's natural properties include a high resistance to weather, rot, termites and even marine borers, making it valuable for a range of outdoors uses. Its density also makes it fire resistant. It can be used in wharf and bridge construction, railway sleepers, cross arms, poles and piles. Construction applications include general house framing, flooring, linings, joinery and fencing. Jarrah's decorative qualities make it prized for use in furniture, turnery, joinery and parquetry.

Properties

Shrinkage

	Very Low	Low	Medium	High	Very High
Tangential:
Tangential:				7.4
Radial:				4 - 5
Unit Movement:				0.3 %

Strength Group

	Very High	High	Reasonably High	Medium High	Medium	Reasonably Low	Low	Very Low
Unseasoned:	S1	S2	S3	S4	S5	S6	S7
Unseasoned:
Seasoned:	SD1	SD2	SD3	SD4	SD5	SD6	SD7	SD8
Seasoned:

Stress Grade

	Structural No. 1	Structural No. 2	Structural No. 3	Structural No. 4	Structural No. 5
Unseasoned:	F14	F11	F8	F7	F5
Seasoned:	F22	F17	F14	F11	F8

Density per Standard

Unseasoned:	1170 kg/m³
Seasoned:	820 kg/m³

Joint Group

	Very High	High	Reasonably High	Medium	Low	Very Low
Unseasoned:	J1	J2	J3	J4	J5	J6
Unseasoned:
Seasoned:	JD1	JD2	JD3	JD4	JD5	JD6
Seasoned:

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:	68
Modulus of Rupture - Seasoned:	112
Modulus of Elasticity - Unseasoned:	10
Modulus of Elasticity - Seasoned:	13
Maximum Crushing Strength - Unseasoned:	36
Maximum Crushing Strength - Seasoned:	61
Impact - Unseasoned:	13
Impact - Seasoned:	10
Toughness - Unseasoned:	Low - up to 15 Nm
Toughness - Seasoned:	Low - up to 15 Nm
Hardness - Unseasoned:	5.7
Hardness - Seasoned:	8.5

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
Lyctid Borer Susceptibility - Other:	8.5
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:

Critical Radiance Flux - Lower:	>2.2 and <4.5 kW/m²
Critical Radiance Flux - Higher:	≥4.5 kW/m²
Smoke Development Rate:	<750

	1 - non-combustible	2 - reasonably non-combustible	3 - slightly combustible	4 - combustible
Fire Properties Group Number:

Average Specific Extinction Area:	<250
Bushfire Resistance:	BAL 12.5 and 19 – All AS3959 required applications

Description

Botanical Name:	Eucalyptus marginata
Preferred Common Name:	Jarrah
Species Type:	Hardwood

Appearance

Jarrah is renowned for its rich red colours that deepen over time. The heartwood ranges from deep browns to burgundy hues. Jarrah sapwood exhibits shades from pale yellow to pink-orange. The timber displays a moderately coarse and even textured grain. The occasional incidence of wavy and interlocking grain produces some samples with a sought after fiddle-back figure.

Common Applications

Jarrah has a history of use in engineering applications such as wharf and bridge construction, railway sleepers, cross-arms, piles, and for road bases. Its structural applications include posts and poles, framing, flooring, lining, decking and cladding.

A highly versatile timber, Jarrah can also be used for woodturning, making it useful in the manufacture of high quality indoor furniture and weather resistant outdoor furniture that stands the test of time. The wood is also prized by luthiers for creating guitar and banjo necks.

Common Form

Sawn, Veneer

Workability

Jarrah is easiest to work when it is green. Once seasoned, it is relatively easy to work, despite its density, if tools are maintained in sharp condition. Jarrah timber can be machined and turned easily. When using it in a planer, the blade must be set to 15 degrees to give the best surface quality. It can be glued and satisfactorily steam bent, but care must be taken when using nails, due to the density. Jarrah timbers readily accept paint, stain and polish.

Origin of Timber

Readily Available

Availability - Further Information

Jarrah can only be sourced from old growth and native forest regrowth in Western Australia, where it is more commonly available. Many of these forests are now reserved and little to no Jarrah is currently grown in commercial plantations. This limits supply and Australia grows few other readily available species with Jarrah’s distinctive colour and character. While some recycled material is available, this is also a restricted resource as it relies on the demolition of existing buildings.

Source of Timber

Native Forest

Applications

Architectural Roof Trusses

Architectural timber roof trusses create strong visual impact. Often used as part of ‘cathedral ceiling’ systems, timber can be specified light or heavy to suit the chosen theme and style. On finish, they can be left natural or may be oiled, stained, painted or highly decorated. Choice is limited only by individual style and design preferences.
Decking

Timber decking creates spaces that are functional, practical and aesthetically pleasing to the eye. 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.
Doors

Timber is one of the most popular and superior material choices for both internal and external doors. Whether manufactured from solid or engineered timber, there are many stylish and practical options that won't compromise on strength and structural performance. A distinctive timber door can also create visual impact, adding value to any commercial or domestic building.
Exterior Stairs

For outdoor applications, timber is one of the leading material choices. Timber use in external staircase applications creates structures of strength and durability, sheathed in a natural beauty that blends seamlessly with the outdoor environment.
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.
Framing

Since people began building simple shelters, wooden framing has played an important role in shaping structures of many kinds. One of the most popular types of wooden framing is known as lightweight timber construction.
Interior Rails and Balustrades

With its natural beauty and inherent strength, timber is a popular material choice in internal balustrade construction. Commonly built from treated softwoods and durable hardwoods, interior balustrades and handrails are typically finished with a clear lacquer to generate the most natural result.
Interior Stairs

Timber should be the material of choice for designers seeking internal staircases of strength, beauty and durability. The construction procedure described here applies to most general type stairs of either conventional or contemporary construction.
Internal Paneling

Timber paneling creates interiors as warm as they are stylish. Commonly utilising an MDF or plywood substrate, internal timber paneling is natural and versatile and comes as either solid natural timber panels or as sheets of engineered wood products
Pergolas

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

Lateral loads such as wind or earthquake on framed timber buildings - either post and beam or stud and joist - need to be resisted and shear walls and diaphragms offer an effective and economical solution.
Structural Timber Poles

Timber poles are utilised in structural construction to provide support for gravity loads and resistance against lateral forces. Not only serving a structural function, timber poles provide many aesthetic benefits, with their use in construction often complementing architectural designs aimed at harmonisation with the natural environment.
Timber Joinery Products

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

Mouldings are extremely versatile and durable, enhancing the aesthetics of any interior and functioning as the icing on the cake for designs with a focus on beauty and splendour.
Timber Portal Frames

For buildings that require large spans and column free interiors, timber portal frames provide one of the most aesthetically pleasing solutions. Utilising modern engineering technology, portal frame design transforms timber into a highly effective, efficient and economical structural product. This application guide provides a comprehensive overview of the process of using timber in the specification, fabrication and erection of portal frame structures.
Windows

With natural aesthetic appeal, versatility and sound structural performance, timber provides excellent window joinery design options. Whether stained to bring out natural tones, or painted to compliment particular décors, timber windows can be tailored to suit a huge variety of styles and can be installed into any type of building.

Case Studies

Joy Yeo Performing Arts Centre, Roseville College

In Roseville College's Joy Yeo Performing Arts Centre, the use of Jarrah and Rose Gum pleases the ear as well as the eye.

Applications: Flooring, Internal Paneling,
National Portrait Gallery, Canberra

Jarrah, Spotted Gum, Blackbutt and Victorian Ash play an essential role in the National Portrait Gallery’s expression of Australian identity.

Applications: Architectural Roof Trusses, External Cladding, Flooring, Framing, Interior Stairs, Internal Paneling, Windows,