Jarrah is a type of Australian Hardwood that commonly used in joinery, flooring subframes and timber decks through Australia. It has become popular in Australia over the years and it is often touted as “tough” and “Classy“.

Jarrah Timber trees are predominantly found in South-Western Australia, due to the lateritic soil and
650-1250nm rainfall, where it forms part of a dense forest belt including the Jarrah-Karri forest
and shrub lands.

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A common concern among home owners with Decking Installations especially the Do it Yourself “crew” is the stability and suitability of timbers used for Decking. Timbers are generally classed according to their durability ranging from class 1 timber (very durable) to class 4 timber (non-durable).

Jarrah is a class 2 (durable) hardwood and is therefore suitable for a variety of decking purposes in moderate to harsh weathers through all of Australia.


Although class 1 hardwoods such as Spotted gum and and Tallowwood are more durable and can withstand a harsher conditions and last longer when they are in the ground, the increasing difficulty of getting older class 1 timbers has placed Jarrah in a position to serve as an effective replacement for class 1 timbers in most circumstances and it has become a regular material on construction sites throughout Australia.

Jarrah is not suitable for below ground poles and posts, a more stable woods such as Tallowwood and Spotted gum are often used as foundation and subframes.

Consequently, it is not suitable for retaining walls or any application that has it directly in contact with the soil causes it to be in contact with moisture for any extended period of time.
Notwithstanding, Jarrah Deckings has a good track record of being tough,
it is durable and highly resistant to rots and termites attacks when used in the right application.

Also, its beautiful, long-lasting and uniform reddish-brown color will add an allure of coolness to behold in your homes.

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A fresh green Jarrah timber has a density of 1090kg/m3 while a kiln dried Jarrah has about 824kg/m3 density.

Jarrah suppliers offer an array of Decking board sizes and shapes, the most common ones being:

1. 65 x 20mm
2. 85 x 20mm
3. 130 x 20mm

All sizes available as both Reeded Decking or Plain Pencil round Decks.
Also, there are numerous custom sizes offered by different suppliers across Australia and larger pieces can be machined down to almost any size.


Now that you want to use Jarrah for your Decking, where do you get It from?

Perth, the capital of Western Australia, has a large number of Jarrah Decking suppliers willing to ship Jarrah boards to your destination, being the capital city of the “state of Jarrah” it is no surprising that a lot of Jarrah-based Business thrives there. Queensland and N.T also use Jarrah a lot in construction due to the cyclonic requirement in the building code there.

As with all Decks, maintenance is a must if it is to last and retain its brilliance and strengths over time, this can be achieved by sticking to the following rules:

1. Use suitable and correct screw size for fixing decks to sub-frames.
2. Give allowance for cross ventilation in the sub structure.
3. Pre-oil timbers prior to installation.
4. Space boards with an appropriate gap to give room for contraction and expansion.
5. Re-coat Jarrah decking on a regular basis to maintain its color.

Do all these, and you will maximize the life of your jarrah deck.