Lunawood recommends regular surface treatment for Thermowood decking when used in applications subject to varying weather conditions. Surface treatment will help to retain the original colour and reduce cracking and splintering that are typical to wood materials over time.
If left untreated, Thermowood will turn a silver-grey colour due to UV rays. The beautiful grey colour lends an elegant appearance and does not affect the wood’s resistance to decay.
Horizontal surfaces, such as terraces subject to wear and direct weather effects, need suitable protective agents to ensure the mechanical durability of the wood material. In other words, the only way to prevent cracking and splintering over time is to perform regular surface treatment by using terrace oil once every two years or so, for instance.
To preserve the brown tint of the wood, you should treat the terrace immediately after installation using brown pigmented terrace oil intended for thermal modified wood, such as Tikkurila’s wood oil Akva, tinted with TVT 5051 or TVT 5071. Check the correct shades with your paint shop. To retain the correct shade, we recommend repeating the treatment every two years or depending on weather conditions and use of the terrace.
Remember that our decking products are also available factory-oiled.
Make sure you also apply wood oil to all sawn surfaces and extensions.
If you want your decking to grey naturally, you should choose clear terrace oil. Note that clear oil slows down the natural greying of wood, so the gradual change can take a few years and even longer in shadow.
All that is needed to perform basic maintenance of a terrace with Lunawood Thermowood decking during the terrace season is to brush away loose materials and wash with water and a soft brush. Pressure washing is not recommended in order to avoid splintering.
MAINTENANCE WITH OIL
Before oiling, brush away loose materials from the terrace surface. Carefully wash the surface using a detergent intended for decking (such as Tikkurilan Tehopesu). Rinse and let the terrace dry thoroughly. If the surface has a clear film after washing, remove it before continuing. Smooth the surface using fine sandpaper, if needed. Apply 1–2 layers of pigmented terrace oil, such as Tikkurila’s wood oil Akva, tinted with TVT 5051 or TVT 5071. Follow the instructions for the surface treatment agent.
GREYING AND RESTORING THE BROWN COLOUR
If left untreated, Thermowood will turn grey over time. Sun, shadow and surrounding conditions determine how quickly the wood will grey.
If your decking has already turned grey and you want to restore its original colour, you can use a strong washing liquid and/or sanding. After that the surface can be treated normally, for instance with brown-pigmented oil that helps to maintain the colour. See the instructions under “Maintenance With Oil”.
Impurities in the air such as soot or pollen, or metallic dust can cause small black spots on the surface of the decking. In some cases, a decking base containing sulphate combined with water can colour the wood. Black spots can be prevented by using pigmented decking oil right after installing the terrace. Black spots often disappear by themselves over time from untreated decking as the boards turn grey.
Black spots can be removed by following these instructions:
Carefully wash the surface using a detergent intended for decking (such as Tikkurilan Tehopesu). Rinse and allow the terrace dry thoroughly. If the surface has a clear film after washing, remove it before continuing. Smooth the surface using a fine sandpaper if needed. Apply 1–2 layers of pigmented terrace oil, such as Tikkurila’s Akva wood oil, tinted with TVT 5051 or TVT 5071. Follow the instructions for the surface treatment agent.
Learn more about Thermowood decks:
Lunawood Thermowood decking products