The roof is made of cold-formed, Z-shape steel purlins, to which profiled steel panels are attached. The steel purlins are galvanised on both sides with a zinc layer with a total thickness of 275 g/m² (Z-275).
The roof panels are galvanised on both sides, covered with a white polyester layer.
The roof panels are covered with a damp insulation layer of polyethylene (PE) film with a thickness of 0,2 mm.
Thermal insulation is polystyrene, PIR (polyisocyanurate) or mineral wool plates - the thermal transmittance coefficient U is chosen according the purpose of the building - up to U = 0,18 W/m²K.
The outer layer is made of 1,2 mm PVC membrane in a standard grey colour.
Skylights construction is made of aluminium profiles with filling of multi-chamber polycarbonate plates (thickness 10-25 mm) with U coefficient ≤ 1,3 W/m2. The skylights are installed on a 50-65 cm high base (made of 2 mm thick galvanised metal sheet), insulated with mineral wool.