With a top rating for durability for above ground use and a high strength rating blackbutt wood is a long lasting option for decking.
Australian hardwood durability ratings.
Just as some people have the genetics that allow them to run fast jump high run long distances or bench press heavy weights species of timber also have genetic dispositions that allow them to.
Upwards of 2 20 per square foot for engineered hardwood compared to upwards of 3 40 per square foot for solid.
Class 1 means that timber is projected to last for 50 years in a fully protected area and 50 years outside above the ground.
As 5604 2005 timber natural durability ratings standards australia 2005 3 https.
Class 1 timber durability class 1 is the highest durability rating.
Untreated sapwood is generally regarded as class 4 durability irrespective of species.
Durability rating of heartwood above ground 2 class 3 class 3 class 3.
Australian hardwood species guide version june 2018 ver2 botanical name eucalyptus obliqua eucalyptus.
This is done by testing the floor s resistance by measuring how much pressure is needed to embed an 11 28 millimetre ballbearing halfway into the boards surface.
The durability rating of a species is based on the natural ability of the heartwood of that species to resist decay and insect pests including termites.
Australian hardwood timbers are among some of the world s hardest by the internationally recognised and uiversally adopted janka hardness ratings.
The rating system used in as 5604 2005 timber natural durability ratings is based on the average life range in years of test specimens of sound untreated heartwood 35 mm x 35 mm for the above ground tests and 50 mm x 50 mm for the in ground trials.
Other factors such as blackbutt being weather bushfire and termite resistant also play into it being considered one of the best australian hardwoods for decking.
The durability rating is expressed as one of four classes and is based on in ground field trials of heartwood.
The janka hardness scale is a test used to determine the hardness and density of a hardwood timber and bamboo floor.
Timber species strength durability rating tallowwood f17 f34 class 1 blackbutt f17 f34 class 1 ironbark f22 f42 class 1 spotted gum f17 f34 class 1 blue gum f14 f24 class 2 forest red gum.
As 5604 timber natural durability ratings and as 1604 timber preservative treatment provide guidance on durability requirements for a range of in ground and above ground applications.
Class 1 timber lasts for 25 years if it is in the ground such as a deck pole.
The range is from class 1 25 50 years in ground life to class 4 1 8 years in ground life.