Thermowood Rainscreen Profile - House Land Holz
, , , ,

Thermowood Rainscreen Profile

Thermo-treated wood produced using completely natural methods—heat and steam. The thermal treatment improves the wood’s properties, opening it up to a wide range of applications. Produced from premium quality, sustainable pine with no harmful chemicals. Thermowood delivers high performance in any weather and ages with grace.

  • Can be fitted horizontal and vertical
  • Perfect for cladding, fencing, pergolas
  • Smooth Finish – cutting angle 15°, rounded corners
  • High dimensional stability, durability and decay resistance
Price excl. vat ( VAT added on checkout ) m2 price l/m price
20 x 55 / 70mm £38.99 £2.15 / £2.73
20 x 95 / 120 / 145mm £35.99 £3.42 / £4.32 / £5.22

Stainless steel screws PSE+ Stainless steel screws?

Cladding order form


Project area calculator
(Use this form to calculate square area of your project)
* Required
Board calculator
(Use this form to calculate number of boards needed to cover your project area)
* Required

Thermally modified timber for indoor and outdoor

Timber, harvested and prepared for construction, is a durable material known for its strength and versatility. It serves as an architectural element in structural systems, framing, cladding, decking, and flooring. Although it possesses a warm and natural character that creates an aesthetic appeal, the inherent humidity of timber can cause wood deformation, leading to bending, mold, and rot once the moisture content reaches 23%. However, with the development of new products and production techniques, Thermowood – also known as Thermally Modified Timber – has emerged as a method for creating natural, chemical-free solutions made from certified raw materials.

By reducing moisture content, it does not rot or mold, it experiences no longitudinal shrinking, and ensures high dimensional stability, resulting in a minimum biological life span of 30 years. After analyzing how to apply these solutions in architecture and design, we will showcase indoor and outdoor spaces featuring House Land Holz’s Thermowood products.

Thermally modified wood conveys numerous benefits for outdoor spaces, including resistance to warping, expansion, contraction, and damage from temperature and humidity variations. Moreover, its low moisture content prevents the presence of organisms. These qualities make it suitable for outdoor applications such as decking, siding, and garden constructions.

Thermowood materials come in a wide range of sizes and cross-section profiles, making them adaptable to various building applications and architectural styles. Because of their thermal insulation properties, thermally modified claddings are highly durable in extreme weather conditions. As for their aesthetic purposes, they can be used as primary or complementary covers for different architectural applications. These claddings can be customized with diverse textures and colors, as well as being adapted to horizontal and vertical applications. Their unique profiles are designed to meet the thickness requirements of each project.

Thermowood rainscreen fencing panels

Other Thermowood Cladding Profiles

Beauty, durability and stability — Thermowood is a premier softwood when it comes to exterior cladding. Horizontal and vertical, our range covers many different profiles: Rainscreen, Smooth, shadow gap, V-Groove and more coming soon.
Technical specifications
Wood type: Whitewood (Pine)
Profile cutting angle: 15°
Treatment: None
Density: 420 – 480kg/m³ when moisture content is 6-8%
Lifespan: Proven life expectancy of 25+ years
Quality class: A or AB (A and B mixed)
Thermal properties: 0,09 W/(m K) according EN ISO 13787 + EN 12667
Humidity: Dried up to approx 6-8% (+/- 2%)
Dimensional stability: Thermal modification increases stability
Leaching: As no substances are added during the Thermowood process, no chemical leaching will occur. In addition, as the resin is removed during the process, the problem of resin leakage through the knots or pitch pockets is removed
Working properties: With the lower moisture content after Thermal Modification the timber can be more brittle than unmodified Redwood/ Whitewood
Applications: External and internal cladding and decking, industrial productions like joineries, window and door manufactures
Other uses: Decking, cladding, fencing, joinery, flooring, spa and sauna interiors
Dimensions (mm): 20 x 55 / 70 / 95 / 120 / 145 mm
Available length: From 2 to 5.1 m
Appearance: Medium/ Dark brown.
Insect attack: Without additional treatments Thermowood is not resistant to termites
Treatability class: Resistant
Movement class: Low (A 145mm board can vary 1mm over the year.)
Impact resistance: Medium
Fixings: Stainless steel fixings are always recommended
How to fix: Face fixation with stainless steel ring thigh nails. Pre-drilling is not needed when using our PFS+ stainless steel screws.
Ecological and safe: Thermowood is produced using high temperature and steam. Since no chemicals are added during the process Thermowood contains only renewable substances. Disposal of offcuts can be burned or given into the normal waste system.
Thermowood properties

Thermowood is rated as class 2, which is durable. Life span for this product of around 30 years.

Key benefits of Thermowood
  • 100% natural processing with no chemical additives, biodegradable and recyclable.
  • Superior performance outdoors, indoors or in different weather conditions thanks to special thermal treatment.
  • Possesses high dimensional stability, durability and decay resistance, has colour uniformity and reduced thermal conductivity.
  • No resin leakage, easy to paint or apply surface treatments.

The natural durability of Thermowood means that no treatment of the wood is required and any coatings applied are for aesthetic purposes only. Hovewer, the wood is not resistant to termites. Additional treatments required to protect your boards from termites.

Dimensional stability

One of the benefits of this product is it’s stability, the thermal modification process reduces the moisture content in the board ensuring less movement.

Thermal Conductivity

Thermowood has a thermal conductivity of around 20% less than standard softwoods. The thermal conductivity is y10 to 0.099 W/(m K).


Thermowood has a lower density than unmodified wood. This is the consequence of wood losing some of its compounds during thermal modification. With the equilibrium moisture of 6% (+20’C, RH 85%), the density of our Thermowood ranges from 420 to 480 kg/m3, slightly varying from the structure of wood in a specific batch. The density values settle around 10% lower compared to the untreated northern pine.

Wood density has direct impact on screw holding strength. While nail holding strength appears to be the same to that of untreated wood, due to Thermowood’s lower density, the screw holding strength proves to be 10-20% lower than in regular wood. The results are much better when smaller.

Fire Resistance

Compared with standard timber, Thermowood causes a smaller fire load and its smoke production is lower. This is also due to lower density and smaller amounts of wood constituents and extractives.

According to the European classification standard, Thermowood is classified as D-s2-d0. When treated with fire retardants, the fire class can be brought up to Class B (B-s1-d0).


Our Thermowood cladding, battens, boards and other thermowood products are available in various lengths, from 2m up to 5.1m. The standard board dimension is approx. 95mm, as this is traditionally the most commonly produced width. However, we also offer a range of other widths: 45mm, 55mm, 70mm, 95mm, 120mm and 145mm. The narrower board widths offer a number of advantages, including a wider choice of design options and improved dimensional stability. As an added benefit, narrower board widths are generally rated well beyond their specification.

Thermowood boards are supplied in linear metres based on random stock lengths at the time of order picking. Other sizes may be available on request.

Note: The board widths can change due to changes in moisture content. The boards are kiln-dried to approx. 6 – 8% before processing. Board width can slightly vary between production and installation on site (+/- 1mm). Thermowood cladding is shipped in certain sizes from our warehouse, but a margin of error should be allowed for when making cladding calculations, due to the natural expansion and contraction of the wood.

Thermowood timber quick tips

Thermo-treated wood is blessed with many natural properties which makes it low-maintenance. The low level of moisture in the wood provides natural protection against rot and decay. However, there are a few things you can do to treat and care for the Thermowood to increase its longevity.

Prepare the wood
Sort your lengths

Sort your lengths. Make sure you’ve set them all up. We recommend ordering 10% more to cover waste material.

Know your tools

Thermowood is hard and dense wood. Use professional equipment for best results.

Use stainless steel

We recommend using only high quality stainless steel screws to avoid corrosion and stains on the wood.


OSMO wood protection offers effective multiple protection against UV rays and harsh environmental conditions.

Weight N/A