Merbau is a popular hardwood from South East Asia used in a wide range of applications; from construction to indoor and outdoor furniture.
Kwila, Ipil, Vesi, Johnstone River Teak or Scrub Mahogany
Insia Bijuga

Merbau is a popular hardwood derived largely from areas in South East Asia, Papua New Guinea, the Pacific islands, and northern Queensland. With its high degree of natural durability and strength it is used externally in engineering, construction and marine applications.
Merbau also features in backyards as outdoor furniture, and internally in a range of joinery, flooring and other uses.
Merbau is harvested from tropical forests and, in some cases, may be sourced from forests legally converted to other land uses or where there are inadequate controls. Certified merbau is available in Australia, so it is suggested you check with your supplier. Certification and chain of custody systems, including DNA tracking, will provide assurance that the wood is from legal and/or well managed forests.
In its natural setting in North Queensland, Malaysia, Fiji, Vietnam, the Philippines, Madagascar, Papua New Guinea, Thailand, Solomon Islands, New Caledonia, Vanuatu and Samoa, the merbau species can grow up to 40 metres in height, with a 0.6 metre trunk diameter. The bushy tree, with distinctive local names, will often form a spreading canopy.
The attractive yellow-orange brown hue of freshly cut heartwood deepens or reddens with ageing. This contrasts markedly with the merbau sapwood, which is white, pale yellow or buff coloured. If left untreated, the sapwood is susceptible to lyctid borer attack. Beyond that, merbau is quite resistant to termites and seasons well with kiln or air-drying, exhibiting only a low degrade and very little shrinkage or movement. The grain of merbau can vary but it is usually interlocked or wavy, with a coarse but even texture, often prized for its attractiveness on backsawn material.
It will finish well with paint, stain, and polish although gum bleed is a possibility.
Merbau is a versatile wood product. It is utilised for larger-scale projects and general construction, along with common use for outdoor settings and barbeque trolleys, and for joinery, flooring and fitting purposes. As it turns well and responds to hand tools it can be applied to more specialised work, such as cabinet making, musical instruments, boat building, carving and tool handles.
Shrinkage
Very Low | Low | Medium | High | Very High | |
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Tangential : |
2.50%
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Radial : |
1.20%
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Unit Movement Tangential: |
0.30%
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Unit Movement Radial: |
0.19%
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Strength Group

Very High |
High |
Reasonably High |
Medium High |
Medium |
Reasonably Low |
Low |
Very Low |
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Unseasoned: |
S1 |
S2 |
S3 |
S4 |
S5 |
S6 |
S7 |
S8 |
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Seasoned: |
SD1 |
SD2 |
SD3 |
SD4 |
SD5 |
SD6 |
SD7 |
SD8 |
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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

Seasoned: |
860kg/m3
|
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Unseasoned: |
1150kg/m3
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Joint Group

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

White, yellow, pale straw to light brown | Pink to pink brown | Light to dark red | Brown, chocolate, mottled or streaky | |
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Mechanical Properties
Modulus of Rupture - Unseasoned: |
118
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Modulus of Rupture - Seasoned: |
147
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Modulus of Elasticity - Unseasoned: |
15
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Modulus of Elasticity - Seasoned: |
18
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Maximum Crushing Strength - Unseasoned: ![]() |
59
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Maximum Crushing Strength - Seasoned: |
82
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Impact - Unseasoned: |
18
|
Impact - Seasoned: |
7.7-14
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Toughness - Unseasoned: |
Medium - 15 - 24 Nm
|
Toughness - Seasoned: |
Medium - 15 - 24 Nm
|
Hardness - Unseasoned: |
7.6
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Hardness - Seasoned: |
8.5
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Durability
Low | Moderate | Reasonably High | High | |
(0 - 5 yrs) | (5 - 15 yrs) | (15 - 25 yrs) | (more than 25 yrs) | |
In-Ground: |
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(0 - 7 yrs) | (7 - 15 yrs) | (15 - 40 yrs) | (More than 40 yrs) | |
Above ground: |
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(0 - 20 yrs, usually < 5) | (21 - 40 yrs) | (41 - 64 yrs) | (More than 60 yrs) | |
Marine Borer Resistance: |
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Lyctid Borer Susceptibility: |
Susceptible |
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Lyctid Borer Susceptibility - Other: |
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Termite Resistance: |
Resistant
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Fire Properties
0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | |
EFH Spread-of-Flame Index: |
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EFH Smoke-Developed Index: |
1 - non-combustible | 2 - reasonably non-combustible | 3 - slightly combustible | 4 - combustible | |
Fire Properties Group |
Average Specific Extinction Area: |
<250
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Bushfire Resistance: |
BAL 12.5, 19 and 29 – All AS3959 required applications
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In its natural setting the merbau species can grow up to 40 metres in height, with a trunk of 0.6 metres in diameter. The bushy tree will often form a spreading canopy. Once cut, the heartwood will initially appear as yellowish-brown or orange-brown before deepening to a pale to dark reddish brown. This contrasts with the merbau sapwood, which appears white, pale yellow or buff. The wood grain is variable but usually interlocked or wavy, which produces a ribbon figure on the radial surface. The timber has a coarse but even texture. It has a characteristic oily odour when cut.
Merbau spans a variety of uses in the fields of engineering, construction, marine and furnishings, both for the indoors and outside. It has been utilised for infrastructure projects including cross arms, bridge building, piles, sleepers, posts, wharves and mining timbers. In the construction context merbau is used in framing, decking, treads and other general needs. Many boats, particularly the decks, are made of merbau, as are a variety of vats, musical instruments and tool handles. As a furniture material merbau is prominent in outdoor settings and barbeque trolleys, as well as being valued for turning, paneling, joinery, shop fitting, cabinet making, parquet flooring, carving, veneer, counter and bench tops.
Merbau takes well to paint, stain and polish, however the finish can sometimes be affected by gum bleed-through or oily patches. Its vessels also contain a yellow substance that stains textiles and concrete. It turns well and is relatively easy to work with hand tools, though it can be variable when it comes to machining. It will generally cut cleanly but there may be some blunting or gumming effect on the cutting edges. Merbau tends to split unless pre-bored, but holds fastenings well.
Merbau grows in Australia in a specific region by the Johnstone River and in the Daintree area of Far North Queensland. It is often referred to as Johnstone River teak or scrub mahogany.

Joinery

Decking

Stairs, Exterior

Rails and Balustrades, Interior

Stairs, Interior

Pergolas

Rails and Balustrades, Exterior

Windows

Flooring

A. Lewis & Co. PTY LTD

Allied Forest Products

ATS Building Products

Austim Pty Ltd

Binq Windows & Doors

Branches Timbercraft

Cameron's H Hardware

Coffs Harbour Hardwoods

Decking Perth

Dekhar Outdoors

Fewings Joinery Pty Ltd

Franz Building Supplies

Garde Timber Pty Ltd

Hammersmith

Ludbrook’s Joinery

M1 Timber Works Pty Ltd

McKay Joinery

Meyer Timber Pty. Ltd.

Payne Timber Products

Precision Decking

Ridgewood Timber Pty Ltd

Simmonds

Tasman K.B Pty Ltd

Teal Windows Pty Ltd

The Log Factory

The Woodworkers Company

Timbertruss Northside

TLB Timber

TwentyOne (21) Timbers
