INSULATING MATERIAL BASED ON MINERAL WOOL, INSULATION SYSTEM, INSULATION METHOD
The invention concerns an insulating material comprising at least two insulating layers based on mineral wool, one so-called lower layer designed to be in contact with a support surface, in particular a cover or steel wall or roof section, and a so-called upper layer further away from the support surface, wherein the lower layer consists essentially of glass wool with a density, mv1, ranging between 50 and 120 kg/m<3> and thickness, e1, ranging between 50 and 200 mm, wherein the upper layer consists essentially of mineral wool, in particular glass wool and/or rock wool, with a density, mv2, ranging between 100 and 250 kg/m<3> and thickness, e2, ranging between 10 and 50 mm, and wherein the mass density ratio of the upper and lower layers verifies the relationship: mv2/mv1 >/= 2.5.