Lunawood Thermowood

LUNAWOOD THERMOWOOD is a beautiful, sustainable wood material produced by using natural methods, heat and steam. Thermal modification improves the wood’s properties, thereby expanding the range of applications in which the wood can be used. Thermowood is dimensionally stable, resistant to decay and resin free. It can be used inside or outdoors, in any climate.  Lunawood is an non-toxic natural product which is easy to machine and install.  Lunawood Thermowood is a sustainable and durable choice for facades, solar shades and other exterior applications as well as for interiors. Due the wood material is 100% resin free,  Lunawood is also suitable for saunas.

Thermally modified timber has beautiful brown tone, which naturally weathers over time to beautiful silver-gray patina, if the wood is left untreated with pigmented and UV-protected wood oil.

See our Lunawood Thermowood Fact Sheet for more information (pdf)

Dimensional Stability

Lowered equilibrium moisture content of Thermowood makes it dimensionally stable and the material retains its shape far better than untreated wood. Therefore Lunawood is highly suitable for facades and other exterior applications.

All Climates

Thermowood does not react to changes in temperature or humidy as drastically as untreated wood. Material is proven to work well in different climates.

Weather endurance

As result of thermal modification, Finnish types of woods are transformed into durable, weather endurance building material. LunaThermo D has decay resistance class 2.

Non toxic

Thermowood is produced using only natural methods, heat and steam. Lunawood products are completely natural and free from chemical additives

Resin Free

Resin is removed from the wood during the thermal modification process. As result, the wood does not secrete resin even high temperatures.

Thermal Insulation

Tests have shown that the thermal conductivity of Thermowood is reduced by around 20-25% compared to untreated coniferous wood.

Thermowood Process

Even the ancient Vikings knew that when building defensive fencing for fortifications, poles made from wood with a burnt surface were more durable than poles which had not been treated in any way. Studies on the possible benefits of thermal modification of wood began as early as the 1930s and 1940s in Europe and USA, but the manufacturing process never reached an industrial scale. Decades later, VTT (Technical Research Institute of Finland) became interested in the idea and as a result, the Thermowood process was patented and the brand was launched in Finland at the end of the 1990s.

The Lunawood thermal modification process uses only heat (ranging from 190-212°C) and steam. Lunawood end products are completely natural and free from chemical additives.

The Thermowood process respects the natural properties of wood. The patented production process is based on the gradual thermal modification of wood, wherein the chemical and physical properties of wood undergo permanent change. Thermowood is a registered trademark and may only be used by member companies of the International Thermowood Association. Lunawood is one of the association’s founding members. The quality of Thermowood production is monitored by an independent, external party.

The best raw materials

We use mainly Finnish PEFC-certified wood in our Thermowood production that is sorted in accordance with our specific and strict requirements. The high and even quality of our production is based of a logistics chain that is carefully managed from forest to final product. Together with our suppliers, select and use only the raw materials that are the best suited for our production in terms of type and quality.

Pine (Pinus Sylvestris)

Pine grown in the northern latitudes is our main raw material for Thermowood. We only use sound knotted wood to ensure the high quality of the final products. As a result, Lunawood is known for its top quality.

Spruce (Picea Abies)

The properties and quality requirements of the spruce that we use in production are similar to those of pine. Lunawood uses mainly spruce in the production of exterior cladding boards and other related products. In terms of production, knots are the main difference between pine and spruce: in spruce, the knots are smaller but relatively hard, which makes them break more easily during the processing.

Other species

The high quality of Lunawood Thermowood starts from the raw material. The main wood species modified are PEFC certified Scots pine and Norway spruce, which are graded in accordance with our specific and strict requirements. For Scots pine only sound knotted heartwood originated from top log is suitable for our products. The properties and quality requirements of the spruce that we use in production are similar to those of pine.

Good to know about Thermowood

The following will present some useful advice and recommendations on the use of Lunawood. The purpose of this information is to help you to enjoy all the many benefits of using Lunawood Thermowood.

See also the Lunawood Fact Sheet (PDF) for more information.

See installation guides and brochures

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