 The house should be built in a way that it's not really using any landfill space. So everything that is in there should be usable, reusable in some way and this is possible. Building materials today are a reservoir of toxic stuff very often and a lot of the gluing material or the sealing materials they are filled with with biocides because the mold the fungi are so strong that they degrade everything so it must be heavily toxified and still after 10 years the fungi moves in and destroys it. So that's something where natural materials are often a lot better but there are also challenges. You must know how to use that and that's sometimes not so easy.