Did any of you recently watch the Zac Efron Netflix series, Down to Earth? In one of the episodes, he travels to New York and London to explore what is being done in built-up cities to reduce pollution and promote better air quality and a safe haven for wildlife.

We were inspired by this show, and when we researched further, we realised that you could create these roofs anywhere as long as you have a solid foundation.

There are three types of green roofs to be aware of; lightweight, extensive and semi-intensive. The one we like that won’t require outside help is Extensive. This feature comprises of sedum and wildflowers to encourage wildlife.


Before you try this one at home, there are some elements to factor in;

  1. Safety

Can the building or shed bare the weight of the green roof? To give you an idea, a lightweight green roof weighs between 60-150 kg per square metre, this increases with saturation.

  1. Roof Angle

Your green roof can be flat or at a tilt of 10 degrees. If there is a slope of 20 degrees or more, you will need to place a frame to stop it from slipping.

  1. Waterproofing

Your roof will need to be watertight. Use heavy-duty rubber pond liner to cover the area, and you should be good to go.


Construct Your Green Roof in 3 Steps


  1. Construct Your Frame

Now that you have done your safety check, you can start to work on building your frame. The best material to use is rot-proof wood or lightweight metal. Then make sure that your structure is the same depth as your soil – 10mm minimum.

Use L shape brackets to tie the corners of the frame tight. Remember the water has to go somewhere so make holes to the side of the frame nearest the ground.

Note, if you are creating a flat green roof, you will need to add 10mm of pea gravel over the foundation to ensure water can drain safely.


  1. Add Soil

GrowPro will help you here :-).

Your roof will require between 70 – 200 mm depth of soil to root. The soil will also need to be light (which we can supply) to ensure that a minimal amount of weight is added to the roof.


  1. Start Planting

Now that your hard work is done, you can now enjoy planting your collection of wild and sedum plants. Then sit back and enjoy the wonders of your creation and the wildlife that will follow.


If you need help calculating how much topsoil you require for this or any job, then why not try out our handy Topsoil Calculator.

If you already know the amount you require, then why not check our range of premium grade, screened topsoil. And remember, we deliver nationwide!