Question: what building materials are bad for the environment?
Answer: Nylon and polyester. Made from petrochemicals, these synthetics are non-biodegradable as well, so they are inherently unsustainable on two counts. ... 
Rayon (viscose) This is another artificial fibre, made from wood pulp, which on the face of it seems more sustainable. ... 
Cotton. ... 
Wool. ... 
Manufacturing processes. ... 
Other materials.