The performance and durability of the roofs over time depends on many factors, among which is the location of thermal insulation in the construction. The principle of inverted thermal insulation, places the XPS board on top of the waterproofing layer, keeping it at a constant temperature, close to the temperature inside of the building and protecting it from the destructive effects of ultraviolet radiation and mechanical damage. The XPS board, in this way, protects the waterproofing from:
• high temperature changes: + 80 ° C to -20 ° C.
• failure, due to weather conditions.
• mechanical damage during the construction, use and maintenance of the roof.
It can be used with a wide variety of waterproofing materials, including bituminous membranes. It can be used also with polyurethane and cementitious materials.
Further advantages of inverted thermal insulation are:
• Installation in any weather conditions.
• Installation, without the need to remove the waterproofing layer (eg. on a roof with an existing waterproofing layer).
• Easy to remove, to replace the waterproofing layer or to reuse when renovating the building.
Ravatherm XPS X 300 SL and Ravatherm XPS 300 SL extruded polystyrene boards are the ideal materials for inverted thermal insulation as they offer:
• High resistance to water absorption
• High resistance to water freeze-thaw cycles
• High mechanical strength