Roofing Membranes With The Built-in Vapour Diffusion System

The roofing membranes represent an auxiliary waterproofing layer when used with shingles, tiles or asphalt patterns (they are necessary mainly on the low pitch roofs) or they can be used as the primary hydro-insulating layer on the flat roofs.

The optimum vapour diffusion is ensured by the system of diagonal channels, provided with an anti-adhesive finish.

The roofing membranes are laid directly on the thermal insulation (rockwool, polystyrene), on the sheething or they can be simply hung and bonded on the roof framing members.

Roofing membranes tretaed with the micro-perforation

Those membranes where the vapour diffusion effect is ensured by the micro-perforation of the membrane(micro-holes all over the surface) cannot be laid onto the thermal insulation directly.
Standardly the microscopic holes allow the vapours (water in the form of the gas) diffuse through the material and on the other hand, the membrane stops all fluids from leaking in the roof structure but if there is a direct contact of the mebrane and a dry thermal insulation material, it can cause the thermal insulation will suck the moist which definitely degrades its functionality.

Proper roofing membranes installation

In order to perform well, the roofing membranes must be installed properly, fastened by the adequate means.
All places where the nails or clamps were used must be sealed with the sealing tape.
Often, the problems appear in the valleys, ridge zones or at the drip edge of the roof.
Sometimes the problems are caused by the architects who do not specify the proper underlayment material and regularly the roofing contractors are to blame, who ignore the minimum effective roof pitches or do not check the possibility of chemical reaction between the membrane material and the roof framing surface treatment.

Each roof is different and the roofing membranes must be designed so that they conform with the framing system, thermal insulation and used vapour barrier.