The cleanliness of wood surfaces should be taken care of regularly, as mould spores thrive on a dirty surface and if the wood surface is not cleaned thoroughly before treatment, dirt and mould can, in the worst case, remain "forever" on the wood surface. Good cleaning allows the protective treatment to have the best possible effect, as the water opens up the causes of the wood, allowing the new oil to penetrate better inside the wood.
Terrace cleaning routines include regular dry brushing to remove leaves and other loose dirt from the surface. If dirt adheres to the surface, it requires cleaning with water (and detergent). It is recommended to clean the terrace with detergent about 1-2 times a year and always before oil treatment. Use a pressure washer for cleaning cautiously. Using a pressure washer to clean the terrace can damage the wood due to its excessive pressure. However, pressure washers are available with an optional terrace washer that makes cleaning easier and faster but does not damage the wood. If the causes of the wood have emerged, sanding may also be necessary to achieve a smooth surface.
Before oil treatment, wash the terrace with WOODCARE.GUIDE Mould & Maintenance Cleaner to avoid binding dirt, dust, or other impurities to the wood surface.
Previous wood treatment agents can also be removed with WOODCARE.GUIDE Terrace Wash, which also removes oils and old pigments. An old terrace with dozens of wood oil treatments may require repeating the cleaning several times.
For mouldy, mossy, or algae surfaces, you can use WOODCARE.GUIDE Mould & Maintenance Cleaner. Any grease stains are removed, for example, with RK White Spirit. Read more about How to remove and prevent mould outdoors.
If a film has been formed on the surface of the wood by previous treatment or several layers of oil, the wood should be cleaned with WOODCARE.GUIDE Terrace Wash, which removes the non-breathable film that is harmful to the wood. The film is formed if excess and unabsorbed oil is not removed from the surface, or if the surface has been treated several times with wood oil.
You can test whether there is a film on the surface by trying if the oil is absorbed into the wood. If the oil is not absorbed, there is a film on the surface. After removing the film, the wood oil can be absorbed again and it protects the wood from decay, but at the same time keeps the wood breathable, allowing the soil moisture to evaporate from inside the wood. Please note that after cleaning with WOODCARE.GUIDE Terrace Wash, the surface must always be re-treated.
It is recommended to treat the terrace with wood oil annually. This extends the life of the terrace and facilitates cleaning.