Breathable membrane is a synthetic roof underlay for use under pitched roof claddings. It reduces drafts and assists in moisture management.
Consists of a micro-porous water resistant film, laminated to two layers of non woven spun-bonded polypropylene.
Breathable water resistant film reduces the risk of condensation when compared with conventional kraft papers.
High permeable membrane allows moisture to get of out roof easily, while pitched roof allows the few drop water caused by condensation on the upper surface of breathable membrane to flow down of roof edge quickly. Because the roof membrane has not only the function of breathable, but also the function good waterproof.
As the polypropylene spunbond fabric is water repellent itself, the water drop will not be absorbent by the membrane, but will keep it as round water drop and fall off the roof. So the spunbond roofing membrane is the best choice for this roofing membrane, and it is very cheap compare to other material.