Silicium HT

A new generation sustainable and ecolabelled wood from OrganoWood

Silicium HT has evolved from our unique ecolabelled silicon technology, where we further enhance the durability of wood using a gentle, energy-efficient heat treatment.

The combination of both silicon and heat provides the wood with even better protection than is seen in wood treated solely with either silicon or heat. This is new technology for a new era. A non-toxic alternative to the usual pressure impregnated timber.

We continue to be inspired by nature’s own method of fossilising wood, which makes it immensely durable. To manufacture Silicium HT we have combined a number of tried-and-tested technologies: silicon minerals, heat and a vacuum process.

We use silicon, which is one of the most common elements in the earth’s crust, and a method called organocatalysis to enhance the durability of the wood and create a mineralisation deep inside it. We use heat and a vacuum process to dry the wood and improve the ability of silicon to penetrate deeper into it. Heat has, to a certain extent, a positive effect on the durability of wood. It both removes nutrients from the wood, which makes it more difficult for rot and fungi to take hold and spread, and reduces cracking in the wood’s surface. Use of vacuum technology enables us to lower the boiling point of the process, which gives us the positive effects associated with heat treatment but without us having to expose the wood to detrimentally high temperatures. It also makes the process more energy efficient.

A perfect synergy. That over time produces a beautiful silver grey hue.

Silicium HT decking installed in June 2021; picture taken in September 2021

The colour of the wood

Silicium HT starts out a deep brown colour, which is characteristic of heat-treated wood. However, this brown colour is not permanent, as the wood takes on a silver grey hue over time. Much like all other wood. This is a natural greying process that takes place when wood is exposed to the sun and moisture, although the silicon present in Silicium HT produces a slightly lighter grey hue. The length of time this takes depends on the conditions. In a very sunny location, it may take about a year, but in more shaded areas, it will take longer.

Resinous stains

Softwoods such as pine and spruce contain resin. The resin softens during heat treatment and may then seep through to the surface of the timber. At the same time, the volatile compounds begin to evaporate, which can leave a residual stain of non-sticky solid resin. Some boards may have extensive staining, while others have no stains at all. To minimise resinous stains, all Silicium HT boards are passed through a brushing machine.

Any remaining resin, or resin that appears after installation, fades over time. If you do wish to remove resinous stains, you can brush the wood carefully with a steel brush.