Circular acoustic and thermal insulation foam building materials made from the soft rush.
Medulla is a material research in which circular acoustic and thermal insulation foam-building materials are developed from the soft rush.
The soft rush is a cosmopolite grassy plant with green, upright stems. The stems exist mainly out of a foamy, white pith that is surrounded by strong fibres. Based on the naturally occurring sound absorbing and insulating qualities of the foamy pith and through cutting, bundling (and in case of the acoustics gluing the stems with lignin), completely vegetal and light weighted acoustic and insulating materials are created that can be applied on the wall as acoustic tiles and in the wall as thermal insulation material. These materials can play an important role in the sustainable building goals of the city of Amsterdam by providing circular building materials that lower the use of energy through high quality insulation.
In nature, the soft rush occurs on wet soils in watersides, grasslands and swampy areas. In most countries with a mild to cold climate the soft rush grows as a weed. In the Netherlands, State Forestry removes hundred thousands of kilos of the soft rush each year. This rest stream can function as the raw material source for the production of the soft rush foam-building materials. In addition to that, the soft rush can be cultivated as a wet crop in peat meadow areas, where it can take part in a new form of agriculture named paludiculture that reduces peat meadow oxidation and could decrease the total annual Dutch CO2 emission with2-3%