Appropriate Coatings For Cladding & Decking

Choosing the Right Oil for Durability

Frank Di Stefano and I have previously written about this subject in this publication. So, why am I writing about it again?

Recently, I came across a timber-clad building where the wood stain had badly peeled/ cracked. As it is in an elevated situation, the owners will have to endure a very expensive remedy, as shown in the attached photo. Admittedly, the cladding is exposed to a west-facing wall orientation, which means it had to endure severe weather conditions both in summer and winter. The dark colour has not helped either, as it absorbs heat, placing further stress on the wood below. I always like to see a light colour used for cladding or weatherboards, as light colours reflect sunlight.

Accordingly, I thought I would explain how a quality wood oil product works. Simply put, the coating pictured has just sat on the surface of the cladding, whereas a quality oil-based coating diffuses into the wood and locks in the coating. Because the coating is oil-based, it largely keeps moisture out, giving the product some protection, and assisting board stability.

Our suggestion is to first apply an application of Cutek Extreme CD50 or Intergrain Universal Oil to all surfaces before installation, then another application after installation. Bowens can offer a factory pre-coat application of both products saving time on-site.

Advantages of using a quality wood-based oil coating include:

• Helps maintain the appearance of natural wood.
• A clear application will allow the surface to grey off if desired, while still giving weather protection.
• A colour tint or UV protector can easily be added.
• Can replace the natural loss of oils in most timber products.
• As stated above, keeps moisture gain/ loss in products where stability is important.
• User-friendly and easy to apply.

However, like most external timber products, regular applications are advisable, perhaps every 1 to 2 years depending on weather exposure.

A question that some would ask is why not use light-coloured paint. Again, paint just sits on the surface, and if it cracks, moisture can make contact with the wood underneath. Then the paint film can become counterproductive because it can lock the moisture in, causing rot.

If you have any questions about timber coatings, please don’t hesitate to contact me at [email protected]