Paris Proof Commitment

At COMCAM, we have committed ourselves to the Paris Proof Commitment: the ambition to reduce energy consumption in the built environment by two-thirds and to achieve a fully carbon-neutral built environment by 2040. While this may sound ambitious and far away, in practice it often starts small and close to home.

In 2025, our colleague Machiel Joosse, together with his wife Rianne, inherited the small-scale farm of their (in-laws) in Domburg. Alongside his role as Manager Business Development at COMCAM, this personal step sparked an initiative that shows how agriculture, biobased construction, and energy-saving climate solutions can strengthen each other.

Now, we let Machiel and Rianne speak for themselves here with this inspiring, hands-on example of how the Paris Proof goals can be put into practice.

From idea to experiment close to the coast in Zeeland

It all started in March 2024 with a discovery: the Paulownia, known as one of the fastest-growing trees in the world. But would such a tree also thrive in Zeeland, close to the coast, where wind, salty mist, and soil salinization pose significant challenges?

In July 2024, the first 25 young trees were planted, supplied by a Dutch pioneer who had started experimenting with them back in 2019. As a continuation of the family farm, they decided to expand the experiment to around 200 Paulownia trees, becoming one of the first entrepreneurs on Walcheren to do so.

Paulownia: Ancient Tree, New Opportunities

Although the cultivation of Paulownia (also known as the Kiri Tree) is relatively new in the Netherlands, the tree has a centuries-old history. In China, Paulownia has been used for more than 3,000 years in house construction, furniture, and everyday objects. For centuries, the Japanese stored their finest kimonos in Paulownia wood cabinets to benefit from its natural fire resistance in case of fire.

In Europe, the tree has been on the rise for the past 10 to 15 years, especially in Germany, Spain, and Eastern Europe.

In the Netherlands, however, cultivation is still relatively in its infancy. Only 2 to 3 years ago did larger-scale experiments begin.
But conditions in the Netherlands are also changing because:

• Due to climate change, growing seasons have become longer.
• Due to the agricultural transition, with the reduction of livestock farming, less grassland is needed, freeing up space for alternative crops such as fiber crops and woody biomass.

As a result, Paulownia is becoming increasingly interesting both as a building material and as a climate solution by planting more trees. It therefore perfectly fits the search for new, sustainable revenue models for agricultural entrepreneurs, as well as for alternative building materials for the construction sector, which also needs to make a transition.

Why Paulownia?

Paulownia has unique characteristics that make it highly attractive for biobased construction and climate solutions:

• Extremely fast growth: within 8–10 years the tree reaches a trunk diameter of 40–60 cm, and in the first years it grows 4–5 meters per year in height.
• Light but strong wood: often called the “aluminum” among wood species. Surprisingly strong and resistant to warping and splitting, making it highly suitable for cladding, furniture, panels, and lightweight structures.
• Very high CO₂ absorption: compared to other trees, averaging 45 tons of CO₂ per hectare per year over its growth cycle.
• Weather resistant: Paulownia wood has a natural resistance to moisture and fungi, making it suitable for outdoor use without heavy chemical treatments.
• Insulating properties: excellent thermal and acoustic insulation, making it ideal for applications where heat and sound control are important, such as in house construction or the music industry.
• High fire resistance: ignites only at higher temperatures, contains little resin, has strong internal insulation, and forms a protective charcoal layer when exposed to heat. This layer seals off oxygen, reducing the chance of flames burning deeper into the wood.
• Deep root system: improves soil structure and is relatively drought-resistant, making it well-suited for changing climate conditions.
• Regrowth from the root: after harvesting, the tree regrows from the existing rootstock—faster than the first time. Up to 6–8 harvest cycles are possible.

Why bio-based construction offers opportunities

The construction sector is responsible for about 38 percent of global CO2 emissions. The use of materials alone accounts for 11 percent of global CO2 emissions. This is mainly due to the use of energy-intensive materials such as concrete, steel and plastics.

Biobased construction: back to the future

Biobased construction is often presented as something new, but in reality it is centuries old. Wood, straw, loam and hemp have always been building materials. It was only in the 20th century, with the rise of cheap fossil fuels, that we became accustomed to artificial insulation materials such as glass and rock wool, EPS, PUR, PIR and EPS. These offered high insulation values and scalability, but also entailed a dependence on fossil raw materials and a high environmental impact. In addition, thick concrete floors and masonry brick walls lead to a very high material-related CO2 impact.

Biobased construction is therefore not an innovation, but rather a revaluation of age-old knowledge – reinforced with modern applications and scientific insights.

The National Approach to Biobased Construction, adopted in 2023 by the Ministry of the Interior and Kingdom Relations (BZK), sets the ambition that 30% of the materials used in the renovation/new construction of buildings must be biobased by 2030.

Biobased materials offer solutions:

ETS2 and the need for carbon offsetting

In addition,  the ETS2 system will be introduced  in Europe  from 2027. This means that not only heavy industry and energy companies, but also transport and the built environment will pay for their CO₂ emissions. It is therefore becoming increasingly financially attractive for companies and organisations to invest in CO₂-reducing or compensating measures.

Crops such as Paulownia and fibre hemp make a direct contribution:

• New revenue models for agriculture
• CO₂ storage in biomass and soil
• Supply of sustainable raw materials that replace fossil alternatives

The role of fiber hemp

In addition to the Paulownia, we have integrated fiber hemp into strip cultivation as far as we know as the first in the Netherlands. Fiber hemp is a Cannabis sativa plant that is specially grown for its fibers, woods, and seeds, which are used for a variety of products such as textiles, paper, rope, insulation material, oil and animal feed. It is a sustainable plant that does not require pesticides, is good for the soil and stores CO₂ as it grows, making it a popular crop in a circular economy. 

The combination with Paulownia, applied for the first time in the Netherlands on the trial field in Domburg, seems to be a golden opportunity:

In this way, we combine several principles of regenerative agriculture in one system: strip cultivation, biodiversity, wind reduction and dual use of crops.

Conclusion: Innovation through combination

Impression of the visit of the COMCAM colleagues

During the inspiring visit to the test field in Domburg, Machiel Joosse gave an engaging explanation of the possibilities and benefits of biobased building materials. He showcased wooden planks from a mature Paulownia tree, highlighting its exceptional properties such as lightweight, high strength, and natural fire resistance. He also presented fibre hemp, where the toughness and tensile strength of the bast fibres proved impressive – even stronger than steel.

Machiel also introduced various biobased insulation materials, including hemp masonry blocks and insulation made from wheat straw. These materials are not only sustainable and circular, but have also been extensively tested for fire resistance, moisture regulation, and thermal performance. Their natural properties contribute to a healthy indoor climate and enable the construction of buildings with low energy demand and minimal CO₂ impact.

The demonstration clearly illustrated how biobased materials offer opportunities for innovation and new business models in both agriculture and the construction sector. The combination of hands-on experience, personal involvement, and already available solutions provided valuable insights to the attending colleagues into the potential and opportunities of biobased construction.

At COMCAM, we believe that these golden combinations are the key to a sustainable and circular economy…