Knauf Earthwool Insulation is not made from wool, it is manufactured from recycled glass bottles, sand and other materials. It is non-hydroscropic (absorbs and holds practically no moisture from the air around it), non-combustible (won’t catch fire) and will not rot or attract vermin. Earthwool Insulation uses a modern biobased ‘binder’ technology instead of traditional petro-based chemicals such as phenol, formaldehyde and acrylics.