Discover eco-materials. 5 points

These five videos filmed in Wallonia showcase various timber construction methods and multiple eco-friendly or recycled insulation solutions, illustrating the broad array of techniques and materials available for more sustainable building. First, we see timber frame structures, where wooden studs form the skeleton of the house, often prefabricated in workshops and then quickly assembled on-site. Next comes post-and-beam, a more open system offering greater freedom for layout changes. CLT (cross-laminated timber) is also highlighted: massive pre-cut wooden panels can be used for walls, floors, and roofs. Lastly, stacked timber planks (madriers) round out the range of possibilities, each solution emphasizing the lightness, speed of installation, and favorable carbon footprint of wood.

The second major theme is insulation using local or reclaimed materials. For instance, sheep’s wool, a plentiful animal fiber in Belgium, provides both thermal and acoustic comfort. Sea shells dredged from estuaries turn out to be an effective loose-fill insulating material for floors. Hemp, in the form of hemp-lime blocks or hemp concrete, and straw in compressed bales both demonstrate excellent hygrometric regulation, thermal inertia, and improved indoor comfort.

Another highlighted example is cellulose made from recycled newspaper, a perfect demonstration of resource reuse. Blown into sealed cavities, this loose-fill cellulose ensures an excellent thermal performance. Similarly, wood fiber, recovered from sawmill byproducts, and cork from the bark of cork oak trees, can be applied as rigid panels or even left uncovered on façades. Even grass—dried and combined with jute—can form insulating mats suitable for walls or roof structures.

We also discover surprising options such as recycled glass granules, ideal for insulating floor slabs and creating a moisture barrier, or used clothing (jeans and other textiles) repurposed into semi-rigid insulation boards. All these approaches reflect the same goal: to lower the carbon footprint by favoring local sourcing, valorizing waste, or using renewable resources, while significantly enhancing indoor comfort year-round.

Across the different reports, several common advantages emerge:

• Circular approach:

  recycled materials (paper, jeans, glass, shells) avoid landfill and gain a second life.

• Environmental protection:

  wood stores carbon, straw and hemp are grown locally, and waste-derived insulators reduce reliance on virgin resources.

• Quality of life:

  robust thermal and acoustic insulation, effective moisture regulation, and enhanced summer comfort thanks to the thermal inertia of dense materials like wood fiber or cellulose.

Ultimately, these techniques demonstrate the wide range of available solutions for building and insulating sustainably, well beyond conventional methods. Whether it’s a self-build project (using hemp or straw) or larger industrial constructions (timber frame, CLT…), Wallonia is home to many stakeholders and resources supporting the transition to a circular economy and helping reduce the construction sector’s impact on climate and ecosystems.