Tips on How To Install A Green Roof

Green roofs are flat or slanted roofs that are entirely covered or in part with unpotted vegetation, growing over waterproof layers of various materials. Green roofs are extremely environmentally friendly and are becoming increasingly popular across the globe. They are a low maintenance option when maximising unused space and save money in the long run if fitted correctly. In this blog post, we are going to go through a few of our top tips on how best to install your own green roof. 

There are two types of green roofs that you can choose from. These are; Extensive - this is where the soil layer is 6 inches or less. Intensive; This is where the soil layer is more than 6 inches. 

Before getting started

Before starting, there are a few things you must check and need to consider. These include; 

• Is the roof flat or sloping? - green roofs are easiest to install on a flat roof, however, they are possible on a sloping roof too, as long as the rise is up to 3 feet every 12 feet of length. 

• Consideration about weight - A green roof can add up to 30 pounds of weight per square foot, so you must ensure the structure of your roof is sound and can withstand the extra weight to avoid any damage. 

• Insulation - Insulation is only required when it is necessary to increase the R-value for the roof over conditioned spaces. If the space below the green roof is not conditioned—over a garden pavilion or shed—there’s no reason to provide any more insulation. 

• Choosing plants - Ideal plants to survive the summer heat, as well as the extremes of the winter and pests, must be chosen in order for your green roof to survive best. Rooftop temperatures can reach high levels and must be able to withstand extreme heat. You will also want to consider plants that stay green all year round to keep your roof fresh and healthy. 

The Installation Process

The various layers you will need to fit are all readily available from roofers, including our Firestone or Lineflex EPDM membrane. These various layers will prevent any water from soaking in and rotting the roof's decking, but will also prevent roots from reaching the decking and rotting or weakening it. 

Step 1 - Install waterproof membrane

EPDM is the perfect material to use when looking for a waterproof membrane. When sealed and fitted correctly, this membrane will be a sturdy and reliable base for any green roof. You can head over to our other blogs to learn how to fit the EPDM membrane correctly. 

Step 2 - Put down plastic sheeting

Place a 6mm sheet of plastic on top of the waterproof membrane. This will act as the root barrier. 

Step 3 - Add Foam Installation 

Top the first two layers with one or more thin sheets of three-quarter-inch foam insulation suited for contact with damp soil. 

Step 4 - Frame the sides

The sides of your roof need to have mesh gutter guards around, to permit drainage to hold soil in place.

Step 5 - Add soil and plants

Add soil to the surface of the roof and distribute it evenly throughout the space. Once done you can place the plants in place, allowing the taller plants to be exposed to the sun without blocking any smaller ones at the front.