VILPE Alipai Ridge Flow 27 vents are used to improve the ventilation of a building’s attic space. The ventilator should be attached using K-36 Sealing Compound and secured with roofing nails. The adhesive layer should be 0.5–1 mm thick and the membrane should be pressed firmly onto the flange of the penetration piece until a bead of adhesive emerges at the edge. VILPE Alipai Ridge Flow 27 for the ventilation of felt roof structures with a pitch of 27 degrees