Products > Nilvent > nilvent > Overview nilvent Breathable membrane for unventilated pitched roofs and timber frame walls Kingspan nilvent Breathable Membrane Properties Download PDF Water vapour resistance 0.17 MN.s/g Nail tear strength 120 N longitudinal 140 N transverse Roll length 50 m Roll width 1.5 m Thickness 0.6 mm Area per roll 75 m2 Weight 0.14 kg/m2 Weight per roll 12 kg