The non-permeable roofing underlay is a material shielding insulation and roof structure from water vapour penetration from habitable spaces. It is laid between insulation and finishing elements – most often gypsum cardboards. It constitutes a barrier for water vapour forming inside the building, protecting, at the same time, wooden elements of the roof structure and insulation against moisture. The non-permeable underlay fulfils the function of an additional windproofing prevents heat losses as a result of free air circulation and roof draughts.
The correct installation of non-permeable roofing underlays requires application of proper joining bands. It ensures correct functioning of the initial roofing layer and non-permeable layer. Any sealing work and damage repair in membranes or underlays should be performed with the use of purposebuilt bands.
The low vapour permeability membranes are products used as initial roofing in sloping roofs. Their basic task as an initial roofing layer is to seal the primary roofing and protect insulation fitted in the roof structure from moisture. Application of the low vapour permeable membrane as an initial roofing in case of buildings with habitable loft spaces necessitates the use of lower ventilation gaps between the membrane and insulating material in the roof structure
The EUROTOP membrane is a primary roofing layer which improves roofing tightness. It solves the problems related to condensation water accumulating in insulation and roof structure. The EUROTOP membranes can be used as initial roofing of sloping roofs – in case of both habitable and non-habitable loft spaces, and in external walls as windproofing.