Inverted Roof Insulation – Non-Trafficable Flat Roof

Inverted flat roof insulation with a final ballast layer of gravel or pebbles. The roof is accessible only for essential maintenance works. This is a non-trafficable system, suitable for both thermal insulation and waterproofing of flat roofs.

Application method:

• Thorough cleaning of the substrate, removal of all loose or unsound parts, and repair where required.
• If slopes are not present, they are created using lightweight concrete to prevent standing water.
• Application of bituminous coating Arexol Lac (bituminous varnish).
• Installation of bituminous waterproofing membranes using a torch (Ecodien 5 kg or 6 kg are recommended).
• Reinforcement of joints and critical points with bituminous or bitumen–polyurethane mastic Hyperdesmo PB 1K.
• Installation of geotextile fabric 150 gr/m².
• Installation of high-density thermal insulation boards with a minimum thickness of 5 cm (Ravatherm XPS X is recommended).
• Installation of a second layer of geotextile fabric 300 gr/m².
• Final ballast layer with gravel or pebbles.

Note: Optionally, the edge of the bituminous membranes can be mechanically fixed with a special metal flashing, where feasible.