Lightweight Sedum Roof

More and more people understand the importance of greening buildings to counter the negative effects of climate change. A simple way to do this is to install a green roof. Not every roof has the carrying capacity for a Traditional Sedum Roof, let alone an intensive roof garden. So how can these buildings become green?

From grey to green

Fortunately, there is Sempergreen's Lightweight Sedum Roof. This green roof system consists of a drainage layer, substrate roll and Sempergreen Sedum-mix blankets. It can be used to green virtually any roof, from carports to distribution centres. The Lightweight Sedum Roof can be used on roofs with a maximum pitch of 20 degrees. With this system, you can still enjoy the benefits of a green roof, which is always better than a grey roof. In addition to the air-purifying effect of the plants, the capillary action of the substrate roll ensures a large absorption capacity during rain showers and efficient buffering of rainwater.

Sempergreen's lightweight green roof systems

Lightweight green roof systems by Sempergreen for flat and slightly pitched roofs


The Lightweight Sedum Roof is available in three different systems, for 0-5, 5-15 and 15-20 degree roof pitches. We offer these different build-ups so that the plants can flourish on each specific roof pitch with the most suitable system layers. A 40mm thick substrate roll is supplied as standard for this system. For roof slopes between 0 and 5 degrees, a 20 mm version is also available. Then, the maximum saturated weight of the system is 40 kg/m².

Consult the system build-up documents for more (technical) information on these green roof systems. Our Sales staff will be happy to help you make the right system choice. Contact our Sales department here.

Due to its low weight and low maintenance requirements, the Lightweight Sedum Roof is very popular for use on sheds and carports, but it is also extremely suitable for large warehouses and buildings with roofs that can bear less weight.

Click 'n go Light: convenient Sedum cassettes

Installation example SedumtraysFor roofs with a pitch of up to 20 degrees, we also offer the Click 'n go Light Sedumtrays. These Sedum cassettes are very easy to install and are particularly suitable for roofs of private buildings like homes and garden sheds. The cassettes are handy and only need to be placed on the roof, unlike rolling out vegetation blankets, substrate rolls and drainage. This makes Sedumtrays an ideal solution for roofs that are less easily accessible. View the Click ’n go Light Sedum Roof system here for more information.

Just because the roof cannot support the weight of an entire roof garden does not mean that local biodiversity cannot get a boost. Upgrade your Sedum roof with a Sempergreen Biodiversity Package. By doing so, you ensure that insects can spend their entire life cycle on the green roof. In just a few square metres, you will boost biodiversity!

Advantages of the Sempergreen substrate roll

A green roof system with substrate roll has several advantages besides water buffering. For instance, this green roof substrate is 8 times lighter than standard granular roof garden substrate. It is made of long rock wool fibres composed of a mixture of different rocks present in large quantities in nature. The open structure of the substrate allows very good root distribution and growth. The lightweight material is delivered as a roll, making installation of the green roof quick and clean. Finally, this lightweight green roof substrate has a high fire resistance (A1 fire safety certificate) and is sound-absorbing.

How does a Lightweight Sedum Roof project work?

Installing a Lightweight Sedum Roof is easy to do. Click on the image below for installation instructions and instruction videos to see how it works on a flat roof:

Installation video and instructions Lightweight Sedum Roof  

From a slope angle of 10 degrees for the Sedum trays and 15 degrees for the Lightweight Sedum Roof, we recommend using an anti-shear device and adding irrigation. We also recommend performing maintenance on the Sedum roof at least twice a year after installation. Read more about green roof maintenance here.

Traditional or Lightweight Sedum Roof?

If the roof of your project can support the weight of a Traditional Sedum roof, it is recommended to choose this green roof system. This is because roof garden substrate offers more diversity of local flora and fauna compared to the substrate roll in the lightweight system. However, if you are still in doubt between a traditional or lightweight Sedum roof, consult our article "Traditional versus lightweight Sedum roof" for tips and more detailed information.

Projects with a Lightweight Sedum Roof

Wondering what the Lightweight Sedum Roof looks like in practice? To find out, click on the following four green roof projects:

Project example - green roof on AMPO headquarters in Spain Project example - lightweight Sedum roof on commercial buildings in France
Project example - green roofs on sheds in Assen Project example - lightweight green roof on Island home in Sweden

View all system build-ups