Timber Guide.

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We could talk all day about timber. As a carpenter with over two decades of experience in woodwork, there is so much to love and learn about our most cherished resource. In many of our builds, we source and champion recycled and upcycled timber (as well as new) to make standout and eco-sensitive living spaces.

At Ascot, we believe knowledge transfer is important so you can make an informed choice when it comes to timber – not only for your build, but for story that accompanies it. Things to consider when deciding on your next piece of timber include density, strength, aesthetic, age, and bushfire resistance, amongst many other factors.

We are committed to educating our clients on all things timber. Take your time to read our Timber Guide or contact us for more information.

A mix of Baltic Pine, Vic Ash, and reclaimed bi-fold windows from a local tavern creates interest in this island Boathouse.

Finished recycled Blackbutt beams as a feature to the entry of a custom-built home.

In this custom-built home, we heroed recycled solid turpentine wharf timber (stair treads 280x70mm, offset by a 200mm RHS steel centre stringer) for a unique finish.

Recycled red brick created a fitting contrast to a bold design.

Reclaimed & Recycled Wood

	Pro	Con
Quality & Strength	Up to 40 points harder on the Janka Hardness Scale compared to plantation wood, given recycled wood often comes from old-growth trees. This also means the timber is less likely to split or move, given it has experienced up to decades of drying process.	Tends to be heavier. Also often contains bolt or nail fixings, which take extra time to remove, are harder on power tools, and require more manual labour. For this reason, I don’t recommend recycled flooring.
Aesthetic	Due to the ageing and weathering process, reclaimed wood has a desirably unique look that’s hard to find in new materials. Also, its far less problematic.	Given there is such a high demand for this type of aesthetic, recycled wood can be expensive.
Interest	Reclaimed timber has a story to tell, which ultimately adds appeal to your finished project. Sources of reclaimed material include wharfs, bridges, and old buildings (whether demolished or where timber structural beams are replaced with steel).	Usually comes in random lengths and sizes. Special consideration should be taken at the start of the build to source material to ensure no hold-ups to your project. Material size may also influence the design stage.
Size	Recycled timber is very large (it’s not uncommon for post sizes to be 400x400mm in Class A timber). Even if you could source this size in new timber, the risk of the post or beam splitting during drying process is far greater.	Logging in Australia is a contentious issue, and many people are mindful these trees are often sourced from old growth forests.
Bushfire Accepted Timber	Most structural species available far exceed bushfire application requirements up to BAL 29Most structural species available far exceed bushfire application requirements up to BAL 29.	There’s extra cost in manual labour, given the heavy weight of the timber (sometimes needed to be crane-lifted in).

High Density Timbers.

In Australia, there are residential building standards for bushfire protection, aimed at improving the ability of a building to withstand a bushfire. These are called BAL ratings and AS3959. Also relevant is the Janka Hardness Scale, which is a standardised test used to determine the hardness and density of hardwood and bamboo floor.

Australia has a number of high density timbers that provide an inherent natural bushfire resistance. Seven of these are defined as bushfire-resistant timbers and are specified in AS3959. They are solid, dense hardwoods that performed well in extensive fire testing. Whilst the BAL-29 standard specifies high density timber for some applications, they can be used more extensively for peace of mind. AS3959 specifies the use of special timbers in some applications. The most common construction timbers from these lists are:

Code	Description
BAL-LOW	Normal timber and other light-weight cladding materials.
BAL-12.5 & BAL-19	Bushfire-resistant timbers or timber species listed in AS3959 Table E1 (species with density of 750kg/m³ or greater)
BAL-29	Bushfire-resistant timber and sarking to the outside of the frame.
BAL-40 & BAL-FZ	Fire resistance level of 30 minutes (FRL 30/30/30) required. This can be achieved with a moisture resistant fire-grade plasterboard and timber system which will actually give a higher rating (16mm fire grade plasterboard provides FRL 60/60/60).

Bushfire Resisting Timbers (BRTSs)

Blackbutt

Pros	Cons
Readily available in decking	Tendency to surface check and split
Highly durable and hard, Class 1, Janka rating of 9.1	High tannin content – may leech when wet
1 of 7 hardwoods recommended by the building commission for bushfire prone areas	Mostly supplied in random lengths

Kwila (Merbau)

Pros	Cons
Highly durable and dense	High tannin content - can stain whilst drying out
Rot, termite, and weather resistant, Class 1	High environmental impact through unsustainable logging practice
Widely available and versatile sizes	High tannin leach
Comes in long straight lengths and easy to work with
anka rating 8.5 - This is the benchmark for decking

Red Ironbark

Pros	Cons
High rot and termite resistance	Hard to work with
Very high durability, hardness, and density	ends to snap fixing when moving
Widely available	Expensive
Used for over 200 years in heavy construction	Difficult to penetrate with an oil due to density
Class 1, Janka rating of 14	Mostly supplied in random lengths
1 of 7 hardwoods recommended by the building commission for bushfire prone areas	Red ironbark is lyctid borer susceptible

Sivertop Ash

Pros	Cons
Less expensive hardwood decking	Termite-prone
1 of 7 hardwoods recommended by the building commission for bushfire prone areas	Relatively prone to surface check and split
Janka hardness rating of 9.5	Not as durable as other Australian hardwoods
Widely available	Light to medium feature present in timber
Easy to work, excellent for nailing and screwing	Class 2
Accepts coatings and preservatives well
Can be supplied in set lengths

River Red Gum

Pros	Cons
Termite resistant	Some gum veins present in timber
Readily available	Mostly supplied in random lengths
	I have noticed sleepers inground rotten after 10 years

Spotted Gum

Pros	Cons
Readily available throughout Australia	Expensive
1 of 7 hardwoods recommended by the building commission for bushfire prone areas	Can be difficult to work with
Highly durable, dense, and hard, class 1, Janka rating 11	Mostly supplied in random lengths
Widely available	Lyctid borer susceptible
Little tannin leach
Sustainably sourced

Turpentine

Pros	Cons
High rot and termite resistance Janka rating of 12	Although listed as class 2 in ground I have noticed samples seem to buckle and loose integrity - split
Very high durability, hardness and density. Very hard to burn	Very expensive
Personally find it easy to work with