To keep a well-ventilated area behind Cembrit products, use a ventilation profile for allowing air to pass from bottom to top of the cladding, whilst preventing insects, vermin and the build up of debris. To maintain the correct distance outwards, the first plank should be 10mm below the profile.The bottom plank is mounted a minimum of 150mm from the terrain, and 50mm from roofing, balconies and other horizontal structures.We recommend painting the rear of the bottom plank, if the distance is less than 150mm from terrain.