Can we produce high-value building material from resources derived from organic waste-streams? The COMPRO project upcycles cellulose-fibres from retrieved toilet paper and a biological glue produced by bacteria in the Nereda® wastewater treatment process. Together these can be used to yield a fully bio-based and circular composite material called Re-plex. A material that can be of valuable use for the construction sector.

“There's still a lot we don't know about biobased materials. So, we explore and experiment with them to discover what they're capable of.”

Mariet Sauerwein

Research Fellow

Evaluating Re-plex's Durability
To evaluate the durability of Re-plex, the consortium installed a test rig at the Bajeskwartier in Amsterdam. The rig aims to evaluate the material's ability to withstand various weather conditions, including sun, rain, and wind, and the influence of orientation (north, south, etc.) on the lifespan of Re-plex.

The panels will be monitored for six months to determine whether they remain intact, partially biodegrade, or exhibit discolorations. Additionally, researchers will examine whether dirt easily adheres to the Re-plex panels and whether the mechanical properties of the material change over time. The proven Nabasco® material will act as a reference.

Small façade panels made of two types of biocomposite are placed a wooden frame:

  • The black facade panel samples (2.5 x 11 cm) are made of Re-plex
  • The light façade panels are made of Nabasco products 8010

The Re-plex test frame

The consortium developing Re-plex aims to rethink and redesign the flow of resources in urban areas, including building materials, water, food, and energy. The ultimate goal is to transition from a linear, make-waste-throw-away model to a fully circular one. The consortium also aims to close waste streams at the metropolitan level to accelerate the transition to a circular society. With the development of Re-plex, the consortium is hoping to revolutionize the construction industry and pave the way for a more sustainable future.

The development of Re-plex is a collaborative effort by leading organizations in their respective fields

  • TU Delft conducts research into biopolymers and wastewater treatment
  • ChainCraft aims to identify new routes for the application of Kaumera
  • NPSP is an expert in the production of high-performance lightweight biocomposites
  • AMS Institute aims to accelerate the transition to a circular society by closing waste streams at the metropolitan level
  • BAM Infra Nederland and BAM Bouw en Techniek are increasingly using circular building materials in their construction projects, and Re-plex could be one of them

The development of Re-plex was partly funded by RVO.


COMPRO: resources from wastewater

Circularity in Urban Regions

We can produce high-value building material from resources derived from organic waste-streams. The COMPRO project upcycl


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