Installation green roof

Please find below a written instruction for the installation of a traditional green roof. This installation instruction is suitable for roofs with a maximum roof pitch of 20 degrees. Click on the button below to download this instruction as a PDF.

STEP 1 – Clean the roof
Clean the roof and remove dirt, waste or other materials. Check that the roof covering is not damaged, to make sure that the roof is waterproof.

STEP 2 – Apply root barrier foil (optional)
If the roofing is not root-resistant, it is necessary to use a root barrier foil. Also cover the roof edges. Make sure the foil joins well by means of an overlap of 50 cm.
 

STEP 3 - Apply protective cover (optional)
Roll out the protective cover up to the roof edge and cut to size. Make sure that the protective cover joins well by means of a small overlap.

STEP 4 – Apply drainage layer
Roll out the drainage sheets to the roof edge, perpendicularly over the root barrier foil (see the direction of the arrow). If necessary, prepare the cutting of the drainage to size on the ground or take measures to cut safely. Never cut directly on the roofing. The installation instructions for the drainage supplied are described on the product sheet. This sheet can be requested at info@sempergreen.com info@sempergreen.com.

STEP 5 – Apply separation profile
Cut a piece out of the root barrier foil, protective cover and drainage layer at the rainwater  downpipe(s). Cover the downpipe with a wire balloon guard, leaf trap or inspection pit.
Place the separation profile at least 20 to 30 cm from the roof edge, with the base on the side of the gravel strip.

STEP 6 – Apply roof garden substrate
Spread the roof garden substrate evenly with a rake. Prevent the substrate from getting between the drainage tracks. Measure if the substrate is the correct height as indicated in your system structure. Completely saturate the substrate layer with water before installing the vegetation mats.

 

STEP 7 – Apply gravel
Apply the gravel between the separation profile and the roof edge. Bring the gravel layer to the same level of the separation profile.




 

STAP 8 – Apply vegetation blankets
Roll out the vegetation blankets over the substrate layer. Start with the end of the vegetation blanket on top. Carefully roll the end of the blanket back and make sure it is in the correct position at the start of the track. If necessary, cut or saw the blanket to the right length. Tip: use a sturdy serrated knife or saw. Make sure that the vegetation blankets join well without overlap. Any bare patches can be filled with residual pieces of the vegetation blanket.
 

STEP 9 – Irrigate
Water the vegetation blankets immediately after installation, until the substrate layer is completely water saturated. This is necessary for the rooting of the vegetation blankets in the underlying substrate layer.
Water the green roof regularly when the roof is installed during a dry period.

Maintenance and fertilization
The maintenance and fertilization advice for a Sedum roof can be read in the document Maintenance advice Sedum roof.