Kastar is a mixture of earth that contains a lot of gravel to be able to carry out rammed earth. The mixture can be used for monolithic walls and floors. The mixture is packed and delivered in big bags of 1000 kg at the right humidity for immediate export. The Kastar is preferably left visible.

Kastar can be compared to exposed concrete, both are very monolithic and have a comparable thermal inertia, but only Kastar can regulate the humidity of a room, is completely vapor permeable and improves the acoustics of a room.

Made of

  • Brusselian sand from Brussels
  • Recycled sand from Brussels
  • Yperian clay from Brussels
  • Recycled gravel from Brussels

Production process

  • The mixture is poured into a formwork in layers of 15 cm and then stamped into layers of 9 cm thick.
  • For non load-bearing interior floors, the mixture is drawn like a traditional screed and then tamped down to 10 cm thick.
  • After the floor has dried, it must still be protected against abrasion and waterproofness.


Kastar is used for non-load-bearing interior walls and floors.

Environmental impact

It is important to work more locally; much of the pollution now resides in transport. Because we transport earth all over the earth. These materials are mined locally, in this way a lot of transport and therefore CO2 emissions are avoided.