Coming soon: The Exploded View Beyond Building

Printed building elements from the water treatment plant

Omlab, Aquaminerals en EFGF / #printbaarbiobased

In The Netherlands, 180.000 tons of toilet paper is flushed on a yearly basis and burned as waste. Using a special technique, KNN cellulose filters cellulose from the drain and processes it into Recell. Recell is currently applied in constructions, agriculture and chemical industries – as additive, raw material or end product. Omlab 3D-prints with a paste composed of the circular residues cellulose, Kaumera and calcite.

Transforming sewage water into printed stone

The printing material is made of:

  • 60% calcium carbonate from water softening treatment by Aquaminerals
  • 5% cellulose is screened during sewage treatment process
  • 5% kaumera obtained during the Nereda sewage treatment process
  • 30% water
3d-printing the paste

Production process of the building elements

  • The raw materials are mixed into a firm, clay-like paste, which is 3d-printed using an extrusion printhead.
  • For printing the paste, it needs to be mixed and homogenized, this takes half an hour per half liter batch.
  • The material is then printed (half an hour per liter).
  • The material can receive post-treatment with calciumchlorate (5 minutes).
  • Forced drying of the material, to harden the object, takes 1-2 days.
  • The result is a breathing material that feels like stone or ceramic.
A 3D printed wall made of water treatment residuals


The toilet of The Exploded View is printed 1:4. But there are examples in which structures are printed 1:1. Check it out via the button below.

3d-printed toilet in the Exploded View

Environmental impact

  • No nature-unfriendly materials
  • Completely made out of residual flows from water treatment that were previously largely burned
  • The material is not baked, and therefore regenerable


The material is breathable and has a positive impact on the indoor climate. The printed shape allows extra ventilation.

Growth opportunities

This product is still being developed and awaiting test results. For large-scale production, more people, (companies that operate) larger printers and co-investors are needed.

Physical building qualities

Contact & info