Tongue and groove thermowood 420cm (18x141mm)

Tongue and Groove Thermowood 420cm (18x141mm)

The Tongue and Groove Thermowood 420cm (18x141mm) is a high-quality thermally modified wood cladding board designed for excellent durability, stability and a natural modern appearance. The thermal modification process improves resistance to moisture and reduces dimensional movement, making it suitable for demanding interior and exterior applications.

With dimensions of 4200mm in length, 18mm in thickness and 141mm in width, these boards provide a strong and versatile cladding solution for façades, garden buildings and architectural timber projects.

Key Benefits

• Thermally modified wood for improved durability.
• Enhanced dimensional stability and reduced warping.
• Strong tongue and groove connection for a seamless finish.
• Chemical-free heat treatment process.
• Suitable for interior and exterior use.
• Natural and modern wood appearance.
• Stable 18mm profile for reliable performance.

Applications

This thermowood tongue and groove cladding is suitable for a wide range of projects, including:

• Facade cladding
• Garden rooms
• Saunas
• Summer houses
• Cabins
• Exterior wall cladding
• Interior feature walls
• Architectural timber designs

Specifications

Installation

Install the boards on a straight and ventilated timber subframe to ensure long-term stability. Maintain sufficient airflow behind the cladding and use stainless steel or corrosion-resistant fixings to prevent staining. Allow the boards to acclimatise before installation for best results.

Maintenance

Thermowood requires minimal maintenance due to its improved stability. For exterior use, a UV-protective oil can be applied to preserve the natural colour. Without treatment, the wood will gradually weather to a silver-grey patina over time.

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How to Install Thermowood Tongue and Groove Cladding

1. Prepare a straight and ventilated timber framework.
2. Install a breathable membrane if required.
3. Allow boards to acclimatise before installation.
4. Start fitting from the bottom upwards.
5. Connect boards using the tongue and groove system.
6. Fix with stainless steel or corrosion-resistant screws.
7. Ensure proper ventilation behind the cladding.

Frequently Asked Questions

What is Thermowood?

Thermowood is wood that has been heat-treated without chemicals to improve durability, stability and moisture resistance.

Is it suitable for outdoor use?

Yes. It is ideal for exterior façades, garden buildings and cladding systems.

Does it need maintenance?

Only minimal maintenance is required. A UV oil can be applied if colour retention is desired.

Can it be used indoors?

Yes. It is also suitable for interior walls, saunas and decorative applications.

Which fixings should be used?

Stainless steel or corrosion-resistant fixings are recommended for long-term durability.