For centuries, wood has been a trusted building material — and today, it brings unmatched value to greenhouse production. Strong, lightweight and naturally insulating, wood provides the ideal framework for growing plants in a stable, healthy environment.

Naturally durable

Thermowood is not only an aesthetic choice but also a technically advanced and environmentally responsible construction material. Wood is the world’s only renewable structural material, combining high strength-to-weight ratio, natural thermal insulation and low embodied energy compared to steel or aluminum.

For all Lähe greenhouse models, we use exclusively FSC® and PEFC® certified timber, ensuring full traceability from sustainably managed forests. These certifications verify that the wood originates from responsibly harvested sources, maintaining ecological balance and supporting long-term forest regeneration.

Our greenhouses are constructed using durable Thermowood made of Nordic pine or Accoya wood.

Thermowood®

Thermowood is a high-quality, eco-friendly timber that has been heat-treated to enhance its natural properties. Through a precise thermal modification process using only heat and steam, the wood becomes more stable, durable, and weather-resistant — without the use of chemicals.

Thermowood combines the timeless appeal of real wood with the performance needed for demanding outdoor structures. Its durability, sustainability, and beauty make it the perfect choice for greenhouse frames that last for decades.

Heat-treated pine has a rich brown color, giving it a warm, uniform appearance. The treatment enhances the grain pattern, darkens knots and removes resin, leaving a smooth, matte surface. Over time, it naturally weathers to a silvery-grey tone if left untreated.

Why choose Thermowood® for your greenhouse?

1. Exceptional Durability

The thermal treatment process makes Thermowood highly resistant to rot, decay, and moisture damage.This means your greenhouse frame will stay solid and beautiful for many years, even in harsh weather.

2. Dimensional Stability

Thermowood absorbs less water and expands or contracts far less than untreated wood. This ensures your greenhouse frame remains straight and tight-fitting through all seasons.

3. Chemical-Free and Eco-Friendly

Thermowood is produced using only natural methods — heat and steam. No preservatives or toxins are added. It’s completely safe for plants, soil and the environment, making it a perfect material for sustainable gardening.

4. Sustainable Choice

Thermowood is made from sustainably sourced Nordic timber, and its treatment process is 100% chemical-free. It’s an environmentally responsible alternative to pressure-treated wood or plastics.

5. Elegant Appearance

The deep, rich brown tone and smooth texture of Thermowood give your greenhouse a warm, natural character that blends beautifully with garden surroundings. Over time, it weathers gracefully to a silver-grey patina if left untreated.

6. Low Maintenance

Thanks to its enhanced durability and stability, Thermowood requires minimal upkeep. Occasional oiling and gentle cleaning will preserve its colour and ensure long-lasting performance.

Accoya® wood

Accoya® is one of the most advanced wood materials available today — a result of combining sustainably sourced timber with a unique acetylation process that transforms the wood from the inside out. The result is an exceptionally stable, durable, and environmentally friendly material, ideally suited for outdoor structures like greenhouses.

Accoya wood has a light, natural appearance with a pale blond to honey-colored tone that remains consistent throughout. The acetylation process stabilizes the wood, reducing color variation and enhancing its smooth, even texture. The grain pattern stays visible, giving the surface a clean, refined look. Over time, uncoated Accoya weathers to an attractive silvery-grey patina.

By choosing Accoya®, we combine nature’s best renewable resource with cutting-edge innovation. The result is a greenhouse structure that embodies strength, sustainability, and timeless beauty — a perfect harmony between science and the natural world.

Why choose Accoya® for your greenhouse?

1. Unmatched Durability

Accoya® wood offers outstanding resistance to rot, decay and weathering. It performs reliably for decades, even in constant contact with moisture or varying temperatures — far exceeding the lifespan of most natural timbers.

2. Exceptional Stability

The acetylation process modifies the wood’s cell structure, reducing its ability to absorb water. This means Accoya® barely swells, shrinks or warps, ensuring that every greenhouse remains precise in fit and form through every season.

3. Sustainably Sourced

Accoya® is made from responsibly harvested, fast-growing softwood. Every stage of production — from forest to finished material — supports environmental responsibility and circular design. The result is a fully renewable, biodegradable material that’s safe for people, plants and the planet.

4. Non-Toxic

Unlike pressure-treated or chemically preserved wood, Accoya® contains no harmful additives. Its modification process permanently alters the wood’s structure using only natural elements, producing a material that’s safe for plants, soil and people.

5. Naturally Beautiful

With its light, uniform colour and refined grain, Accoya® has a timeless, elegant appearance. It can be left to weather naturally to a silvery-grey patina or finished with coatings that last longer than on most other woods.

6. Low Maintenance and Long Life

Because of its exceptional stability and resistance, Accoya® requires minimal maintenance and offers a remarkably long service life. It’s a material designed for performance — and built to endure beautifully.