Thermal insulation of roofs in the attic.
The heat transfer coefficient for thermally insulated pitched roofs should not exceed 0,3 W/m²K, which means, that the thickness of the thermal insulation material should not be less than 18 – 20 cm. The height of the rafters designed for structural strength is usually not enough, so that such a thick layer of insulation can fit in the space between them. A supplementary layer of thermal insulation can be made under the rafters, between the support grating for the plasterboard lining or over the rafters, by using the so-called. overprints from wooden battens, fastened perpendicular to the rafters, spaced at 60 cm.
Insulated sloping roofs require a vapor barrier on the inside, which prevents the phenomenon of water vapor condensation in the thermal insulation layer..