Weathered Timber – Low Maintenace Solution
One of the biggest concerns we find with our clients is the maintenance. Timber, being a natural product, is not able to stand up to the harsh Australian climate without changing. The sun’s harsh ultraviolet rays breaks down the lignin in the cellulose causing photo chemical colour change which occurs in any wood exposed to sunlight. The result is a change in the wood’s appearance from its original colour to a gradual silvery grey sheen. The only way to combat the timber weathering is through regular maintenance or leaving it to weather to a silver grey.
Weathered timber is a great way to minimise maintenance however you do need to choose a stable timber. If the timber is not stable it can start to shrink and cup as the timber starts to weather.
Two low movement species are Pacific Teak and Burnt Ash.
Pacific Teak is a naturally stable hardwood which offers very low shrinkage. This means when exposed to the harsh Australian climate it stays dimensionally stable – perfect for exterior timber applications such as cladding and decking. Read more about Pacific Teak
Burnt Ash is a thermally modified species which means it under goes a thermal modification process that seals the cell structure or ‘drinking straws’ – this greatly reduces movement and increases durability. Read more about Burnt Ash
Disadvantages of Weathered Timber
Weathered Timber doesn’t mean the timber will not need maintenance at all. Wood is hygroscopic, which means its moisture content (MC) will fluctuate based on the relative humidity (RH) of the surrounding air. So to allow timber to weather means timber will be expanding and contracting more so than when it is not protected or ‘waterproofed’ from the outside. Further information on the maintenance frequency required for weathered timber is further down this article. To combat the timber movement you need to choose a low movement timber species like Burnt Ash or Pacific Teak. Further information on timber movement can be found at https://www.mortlock.com.au/timber-movement/
Weathered timber doesn’t weather evenly, different areas will receive different levels of UV, at different times of the day. Eaves, soffits and over hangs will also cause timber to weather at different rates. There are coatings to use like our Sioox Weather Protection which can assist with evenly weathering timber.
Only provides one colour choice, while timber comes in many colour variations it all ends up a silver grey colour.
Advantages of Weathered Timber
Low maintenance. As a comparison to maintain the natural colour of timber you would need to re-coat timber every 12-18 months, weathered timber is around 4-5 years and with the Sioox weather protection system it can be as little as every 10-15 years.
Aesthetics of weathered timber is amazing, especially in areas with the right surroundings. It offers a finish that is very hard to replicate using stains or man made materials.
Cutek Clear Oil Method
Cutek Clear Oil will protect the wood, providing stability and structural integrity while allowing it to naturally lighten to produce a silver weathered patina over time. The soft natural lightening and silvering of the wood represents a low care option and is becoming an increasingly popular way to leave wood in weather exposed settings.
Wood projects using clear Cutek oil that have silvered can easily be returned back to the wood’s original colour if required.
Areas with timber in shaded areas will not weather at the same speed as areas in full exposure, areas not exposed to weather may not weather at all. Timber with Cutek Clear Oil coating needs to be fully exposed to sun for the weathering to be even.
Cutek Weathered Look Steps:
- The first coat of Cutek Clear should be applied to all surfaces of the timber prior to delivery by Mortlock Timber Group
- A second coat of Cutek applied once installation is complete. Any second coat should only be applied once the first coat has completely penetrated and is dry. The time taken for Cutek to diffuse into the timber varies significantly, depending on aspect, species, ambient temperature, porosity and moisture content of the timber.
- A third coat of Cutek CD50 Clear should be applied once construction is complete. Maintenance coats can be applied as often as every 12-18 months to reduce minor surface checking and maintain stability. Typically weathered surfaces can be left up to 3-4 years without maintenance coats. The timber should weather within 12-18 months depending on location and level of exposure.
Further Information on Cutek can be found at https://www.cutek.com.au/
Sioox Weather Protection Method
Sioox weather protection coating is wood modification coating which speeds up the timber weathering process while providing a protective layer over the surface. After application, the coating is activated by moisture and a curing reaction commences which forms a flexible silica surface. Weather Protection Coating is a proven water based silicate treatment which, if correctly applied and cared for, provides long life and a beautiful natural finish.
Sioox Weathered Look Steps
- Timber is pre-coated with the Sioox Weather protection system by Mortlock Timber prior delivery. The protection system consists of 2 parts and 3 coats in Total, Mortlock applies 2 coats of Sioox Part 1, and 1 coat of Part too. Timber is completely dried before the next coat is applied.
- Maintenance re-coat is recommended every 5-6 years however this product can last up to 10-15 years.
This product provides a more even weathered finish than naturally weathered timber. To speed up the process or cause the timber to weather in non-exposed areas, lightly spray the timber with water once coating has been applied every day for 2-3 weeks, the moisture is what reacts with the coating to ensure an even silvering on the surface.
If you have any questions reach out to our team – 1800 953 004.