Balau Decking

Balau Decking

We stock 19x90mm 1st Grade Reeded Yellow Balau decking


Balau is a Malaysian hardwood timber. In its natural form it is light brown in colour.

We stock carefully selected 19x90mm 1st Grade Reeded Bangkirai Balau decking. Quality is very important to us and we source from the best suppliers.

Our decking is machined from kiln dried timber. With proper care it is very durable and suitable for use as exterior decking.


Our Balau decking is reeded (fine grooves) on 1 face. If laid with the grooves on top, sanding and oiling is more difficult, water collects in the grooves, and screws are difficult to hide and countersink neatly. We therefore recommend that it should be laid smooth face upwards.

Due to Balau being a natural product, and usually installed in adverse conditions (i.e. direct sunlight), some movement of the timber can be expected but can be minimized by correct installation. 50mm bearers for good support are advisable. Bearer spacing for 19mm is 450-500mm and plank spacing of 4mm is recommended.


Somerset Timbers stocks good quality Stainless Steel decking screws with a posi drive head. A 4mm or 4.5mm drill bit is recommended for pre drilling. A 60mm length is recommended but 50mm can be used as well. A specialist countersinking bit is recommended – it is difficult to countersink correctly with an ordinary drill bit. Galvanised steel posi screws are NOT recommended due to their relatively short life span. It is not worth the trouble of using cheap screws (e.g. ordinary chipboard screw – stainless or galvanised) on a relatively expensive product.

Hidden decking clips are not recommended. If any movement occurs in Balau decking after installation it has a tendency to lift decking clips.


After installation, Somerset Timbers Galseal should be applied to feed oil back into the timber. Various colours are available.

This can be reapplied as necessary – a 2nd coat probably after 6 months and then yearly. Alternatively Boiled linseed oil thinned with turpentine can also be used.

The use of surface sealers and varnishes is not recommended as this causes the timber to heat up excessively in hot conditions and does not allow the timber to breathe.

If no oil is applied, Balau will fade to a light grey colour. Due to the density fine hair cracks are a characteristic of the timber as it dries over time.

Following correct installation and periodic maintenance, Balau should provide a very long lasting, beautiful surface.

Somerset Timbers Exterior Decking Balau (summary of this page)

Full specification on BALAU timber