Sub-soil testing for identifying clay content, Hvalsø, Denmark

More and more development projects are popping up under the sustainability flag, which should be celebrated. Timber frame construction with blown-in insulation is becoming very popular. Clay finishes are trendy due to their vapour-open property and zero environmental impact. Both materials mentioned above will be used in the Hvalsø-Project.

On the other hand, clay-based materials arrive at the site in bags, “ready-to-use”, very often from another country; this is also happening in this project. Denmark has this fantastic treasure, the excellent clay-rich soil, which can be used in many ways, so why is the bagged clay still imported from other countries?

Eeva-Maarja Laur (MSc) and I decided to contact a self-builder on this site and get his permission to test the excavated soil, which has shown excellent potential at first glance. We investigated the quality of the samples and developed different formulas with local fibres, such as bullrush, straw, and sawdust, for the self-builder's use.