SMARTPLY PROPASSIV is a structural OSB panel with integrated vapour control and air barrier properties for use as structural sheathing in timber frame structures. Airtightness is engineered into the OSB panel substrate, whilst SMARTPLY'S in-house speciality surfacing technology provides an integrated vapour barrier with consistently high vapour resistance over the entire surface. SMARTPLY PROPASSIV meets all the requirements of EN 300 for the production of OSB3 panels and therefore can be installed as any other OSB3 panel.