Install the decking boards with a slope of 1-2% to enable to run off the surface. Ensure good ventilation of the decking by keeping at least 20mm space at walls and obstacles and avoid closing the terance on the sides. When the surface underneath the decking is not fast drying. there should be at least 100mm distance between the decking and the surface undereath the floor.Keep at least 5-6mm expansion space between the boards(in width direction).With our fastener installation this is automatically the case.Because of the stability of the boards and the shape of the head sid tongue and groove no expansion space is needed on the head side. Install the boards on sub frame joists with approx.465mm space between the joists(center to center)so each board is supported by 5battens.Always install the hInstall the decking boards with a slope of 1-2% to enable to run off the surface. Ensure good ventilation of the decking by keeping at least 20mm space at walls and obstacles and avoid closing the terance on the sides. When the surface underneath the decking is not fast drying. there should be at least 100mm distance between the decking and the surface undereath the floor.Keep at least 5-6mm expansion space between the boards(in width direction).With our fastener installation this is automatically the case.Because of the stability of the boards and the shape of the head sid tongue and groove no expansion space is needed on the head side. Install the boards on sub frame joists with approx.465mm space between the joists(center to center)so each board is supported by 5battens.Always install the head sides of the boards exactly on the sub beam.ead sides of the boards exactly on the sub beam.