Start at the lowest point of the roof. Apply the self-adhesive vapor barrier in parallel strips. Ensure that the vapor barrier extends at least two centimeters above the final insulation level on all sides. For example, if you’ve chosen an insulation thickness of 80 mm, apply the vapor barrier at least 10 cm high against the rising edges. Position the first strip of vapor barrier and peel back the thin protective film at the bottom end. Adhere the exposed portion of the vapor barrier to the substrate and against the upstand. Continue slowly, gradually removing the remaining protective film. It’s easier if one person stands on the adhered end while the other pulls the film away. Rub the strip of vapor barrier briefly with your hands. Cut another strip of vapor barrier, overlapping it by about ten centimeters. Apply the edge of the second strip to the orange dotted line on the first strip. Continue in this manner until the entire roof surface is covered. In the final step, you probably won’t have enough width to apply a full strip of vapor barrier. Then cut horizontal strips from the roll of vapor barrier, overlapping them by ten centimeters at the bottom with the last full strip of vapor barrier and overlapping them at the sides. TIP! At temperatures below 10°C, it’s helpful to slightly warm the vapor barrier with a hot air blower. This will help it adhere better.
What do you need?
Vapor barrier, utility knife, and folding ruler.Instructional video vapor barrier
Manual
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