Standard sand and cement screed weighs approximately 2000kg/m3. The weight of tapered insulation systems vary, depending on insulant type, however, all are of significantly lower weight than screeds. For example, the weight of tapered insulation using a rigid polyisocyanurate (PIR) insulant, is typically 32kg/m3.
Even using the relatively heavier rock mineral fibre, the weight is only up to 180kg/m3. Hence tapered insulation offers a huge benefit by reducing additional weight on structures.