RAVATHERM XPS 300 ST plates are suitable for simple, quick, thermal bridge free thermal insulation of pitched roofs with reinforced concrete structures. Its main advantage is that similar to the inverted roof, RAVATHERM™ XPS 300 ST does not require any protection against rainwater or snow during implementation.
The closed-cell polystyrene foam plates must be must be laid down starting from the lower edge of the slanted slab in a way to make a continuous surface, in an offset binding based on the fastening plan, anchoring them to the reinforced concrete structure through the predrilled counter battens.
HIGH THICKNESS THERMAL INSULATION
In the case of thermal insulation with a large thickness (≥120 mm), it is recommended to install the thermal insulation in two layers. In the roof slope direction, impregnated fastening slats with 50/75 or 60/80 mm cross sections should be mounted to the reinforced concrete structure through the vapour barrier. Between the fastening slats, precisely tailored, 50 or 60 mm thick RAVATHERM™ XPS 300 ST thermal insulation should be fastenen pointwise by a solvent-free cold adhesive, or adhesive foam (e.g. INSTA-STIK). The bottom line must be mechanically mounted to the slab as well. In a way to make a continuous surface, the second layer of the RAVATHERM™ XPS 300 ST thermal insulation must be screwed to the pre-positioned fastening slats through the predrilled counter battens, in an offset binding, similarly to the wooden structure roofs