Roofs & Pitched Tiled Roofs: Thermal Insulation and Waterproofing

The roof bears the greatest thermal load of the building envelope in summer and is a critical point for heat loss in winter. Here you will find the two basic thermal insulation arrangements for pitched tiled roofs: insulation above the slab or roof deck using XPS boards in an ‘M’ configuration, which eliminates thermal bridges and leaves the rafters exposed, and insulation between the rafters using stone wool, which offers the added benefits of fire protection and sound insulation. Also covered are vapour barriers, breathable and reflective underlay membranes, the ventilated cavity, and the selection of thickness according to the KENAK climate zone. ARGYNET specifies the layering and calculates materials and fixings per m².

Solutions (3)

FIBRANxps XPS panels laid on a timber roof deck, with a breathable membrane on the adjacent wing

Thermal insulation and waterproofing of pitched tiled roofs

Roof & pitched tiled roofSystem solution

Insulation over the load-bearing structure using XPS: zero thermal bridges, exposed trusses — and the fixings that keep the roof in place in windy conditions.

Four thermal insulation materials for external wall insulation: stone wool, white and graphite-containing EPS, and XPS

What is the correct thickness of insulation for my area? (Climate Zones)

Exteriors & external wall insulationSelection guide / comparison

Correct thickness = climate zone × λ coefficient. Umax per KENAK zone, comparison of insulation materials and the altitude rule.

Mineral wool installed between the timber roof trusses, prior to the internal cladding

How do I insulate my roof?

Roof & pitched tiled roofSelection guide / comparison

Mineral wool is the easy bit. The two sheets surrounding it and their arrangement determine whether the roof will rot from the inside.