Waterproof membrane uses the very latest technology of high quality microporous membrane.This material has many tiny holes which permits air vapor to get through but prevents water molecule to get through. Thus the performance of waterproof and breathable. Breathable membrane consists of three layers: Outer shelter layer, middle function layer and inner shelter layer. The two shelter layer keeps the membrane durable in every kind of using environment. House wrap advantages: Breathable membrane for roof air tightness:Correctly installed PANZHU WRAP can protect the house from strong wind and reduce the thermal bridge phenomenon in the inner house Breathable membrane for walls water tightness: Excellent waterproofing performance with 2 meters water column up and two hours water tightness Breathability : 1063g/ã?¡.24h or 68 US perm The house can breath freely with PANZHU WRAP and keep away the mold and rod. Durability: PANZHU breathable membrane has passed the national aging test.Tensile strength 232N/50mm.