Skip to toolbar

How to Install a Green Roof

A green roof is a special type of roof that is covered with certain types of vegetation. This vegetation can cover either all or parts of the roofing. Green roofs have many advantages and can be installed with relative ease.

Installing a Green Roof

The first step in installing a green roof is to place a waterproof membrane on the roof to protect it from water damage. Roofs can fail quickly due to water damage, so a waterproof membrane is a must. They come in many different varieties, from asphalt to liquid membranes.

The next step is to add a root barrier. Two good choices to use are concrete or cellular glass. Root barriers protect the roof from roots attempting to grow around and through it, causing costly damage. It’s important to use an extra layer of concrete or other barrier material if you are using an organic waterproof membrane such as asphalt.

The next step in installing a green roof is adding a drainage layer. This layer should be made of pumice, gravel, and similar materials. Drainage layers are necessary to send excess water to the roof’s gutter system.

Filter fabric is placed over the drainage layer. The filter fabric serves the important function of keeping the growing medium in place. This filter needs to be porous so that water can drain properly. Polyester is a good material for a filter fabric. Polypropylene works well, too.

After putting all this together, it’s time to place the growing medium upon the roof. This should be a mixture of sand, crushed clay, topsoil, and humus. The depth of the soil mixture should be about three inches or more.

With the proper soil ready, now you need to install drip irrigation. Drip irrigation will save you a lot of hassle by giving the proper amount of water to the roots as needed. Fertilizer can also be given to plants by drip irrigation.

Plants should be added next. The type of plants placed on your roof should be able to handle the climate you live in. They also need to be able to tolerate sun, wind, and frost or heat exposure. Avoid placing small trees on the roof; they need too much soil depth and are too heavy for the roof.

Finally, don’t forget to add a wind blanket to protect your plants from erosion.

Benefits of Installing a Green Roof

Green roofs have many benefits. They can improve water quality by reducing nitrogen and other pollutants by filtering water. When rain falls, the growing medium stores it, and the plants filter the water so any runoff is made much cleaner.

Beautification and Biodiversity

Green roofs transform the dreary gray of a building top into a lush, green paradise. These green roofs also promote biodiversity and provide habitats for various animals. Bees, butterflies, and other insects can find nourishment and purpose on green roofs, and ground-nesting birds can find a home on a green roof.

Cooling Benefits

Green roofs help cool cities and mitigate the urban heat island effect. They absorb light that would otherwise turn into heat energy, and their dew and evaporation cycle helps to cool the surrounding area.

Air Purification

Green roofs also can filter toxins and pollutants in the air. In addition, they can reduce the amount of carbon dioxide, lessening the effects of global warming.

Article by Wayne Rogers, a freelance blog writer. He specializes in subjects pertaining to green home improvement. When roofing in Houston, Texas he believes a green roof is a viable option for any home or business.