Roofing membrane is a modern and commonly used for roofing purposes material, which replaces roofing felt. Roofing membranes are easier to mount, cheaper and lighter, and due to their properties, they effectively protect the attic and the thermal insulation against moisture, wind and dust, as well as against the leaks that occur as a result of roof damage.
Foils with a vapor barrier film regulate the flow of water vapor and represent a necessary protection layer for roofs from moisture.
Membranes are technologically advanced products. Every membrane „breathes”. It allows the evaporation of moisture accumulated in the building structure during the construction and produced by building materials for many months after the building is put into the use.
The vapor permeability of membranes is determined by the SD parameter. The Sd value for the mentioned membrane consider the thickness of the air layer (expressed in meters) with the same vapor permeability as membrane has. For example, roof membranes with Sd = 0.02 [m] have the same negligible diffusion resistance as an air layer with a thickness of 2 centimetres.
Due to its high vapor permeability (Sd from 0.02 to 0.15 [m]) they can be used as a coat on the thermal insulation layer (without a ventilation gap). In addition, selected membranes can be mounted directly on roofs with full boarding.
Roofing membranes with a vapor barrier film are designed to make a vapor barrier in the construction of roofs, walls and ceilings. These films also represent an excellent anti-moisture layer, including various types of floor coverings. Moreover, the use of the vapor barrier film is necessary to maintain adequate roof protection against moisture. The main product feature is a high water and vapor tightness, which is presented by high values of the water vapour transmission properties (Sd) - in the range from a few to hundred meters.