Up to 8–12 years, depending on how exposed the deck is, the quality of the wood and its condition when first treated. Many people extend the effect by reapplying an additional coat of Surface Protection Deck after 4–5 years.

SiOO:X impregnation forms a protective and dirt-repellent coating that also penetrates a fraction of an inch into the wood, which strengthens and binds the wood fibers from within. This improves resistance to mildew and fungal spores. To minimize risk of unwanted growth, it is important to keep the surface clean (preferably with our specially developed Maintenance Wash) and dry since spores and algae thrive in dirt, moisture and shade. By doing so you will protect vulnerable places such as areas under bushes, flower pots, furniture, etc. Nevertheless, if green or black (small black dots) growth should occur, we recommend first gently cleaning with our Maintenance Wash, lukewarm water and a soft brush. An algaecide may be needed for more resistant cases, but preferably diluted with plenty of water. If more aggressive treatment with a brush is needed, additional application of surface protection may be required after washing. Green algae can grow on any material and surface texture not coated with active toxin and are especially prolific in spring and summer following mild winters. This has become a growing problem in Sweden (with the exception of the far north) and has long been a problem in southern Europe.

SiOO:X Premium Deck is used for pressure-treated pine, larch, hardwoods, heart pine, thermo-treated wood, oak, cedar, etc. SiOO:X Premium Panel is used for sawn spruce and larch paneling, heart pine, cedar, hardwood, thermo-treated wood, timberframe houses and pressure-treated pine. SiOO:X Original products can be used on pressure-treated wood. They can also be used on any other wood suitable for outdoor use, but you should expect a shorter life span. But it is important to choose the right product for the type of wood and conditions. Read the product descriptions and ask if it is unclear which product is right.

The treated wood is initially yellowish brown and a little blotchy. The curing and bleaching process starts on contact with water, and after 2–4 weeks your deck will begin to have a lovely, even silver-gray color.The process then continues for up to 1 year. The change in color is mainly driven by water from rain and moisture in the air. In this process, the SiOO:X products gradually mature and form solid protective silicon structures inside the wood.The smooth, strong silver-gray surface gradually builds up. Following the first few rainfalls, light and sometimes dark blotchy areas form where standing water has occurred. Note that this is completely normal for the SiOO:X technology and is not harmful. It is actually the first step in the process and will ultimately even out. Be patient and wait a month or more for the lovely SiOO:X surface to emerge. If any part of the surface treated with SiOO:X is under roof or otherwise protected from rain, you can speed up the process by thoroughly soaking the surface with a gentle spray until the water soaks through the surface protection. Important: do not use high pressure, which will instead wear away the surface protection. Use a soft brush to work the water in.Deck surfaces under small overhangs will lighten, but it may take longer.