Important safety notice. Please do not build hexayurts out of any flammable material. In the past, people have built them from non-fire rated materials including polyisocyanurate insulation (Tuff-R from Dow, often sold at Home Depot.) I do not regard that as safe if the building is exposed to sources of ignition like open flame, or mains electrical devices. Any non-fire rated substance should not be used for camping, and is generally suitable only for demonstration purposes.