Reducing Surface Runoff With Green Roofs

The benefits of green roofs extend far beyond their obvious aesthetic appeal.

As we face prolonged spells of wet weather,  green roofs are proven to play a key role in helping to significantly reduce the surface runoff volumes and rates of rainfall leaving roofs. 

As a proven control mechanism in the SuDS (Sustainable Drainage Systems), green roofs can help to effectively combat the potential for flash floods as a consequence of intense rainfall events.

This excellent video from the STRi Group highlights how green infrastructure can be used to help store stormwater on sites.

What are SuDS and how do they work?

In urban areas where many surfaces are sealed by buildings and paving, natural infiltration is limited. Instead, drainage networks consisting of pipes and culverts, divert surface water to local watercourses. In some cases, this has resulted in downstream flooding and deterioration in river water quality caused when foul sewers are overwhelmed by surface water leading to a release of dirty water into rivers.

Sustainable drainage systems aim to alleviate these problems by storing or re-using surface water at the source, decreasing flow rates to watercourses and by improving water quality.

Please click here for more on SuDS and its benefits from the British Geological Survey.

How Can Green Roofs Help?

Green infrastructure technologies, such as permeable pavements, bioswales, cisterns and green roofs, are now commonly recommended to confront extreme weather events.

Green roofs are a green infrastructure (GI) option that can be applied to virtually any rooftop given weight load capacity. The benefits of green roofs extend far beyond their obvious aesthetic appeal.

A study done by University of Toronto civil engineer Jenny Hill and co-researchers at the school’s Green Roof Innovation Testing Lab (GRIT Lab) showed that green roofs have the capacity to capture an average of 70 per cent of rainfall over a given time, relieving underground storm-water systems and releasing the rainwater back into the atmosphere.

Introducing The M-Tray®

Wallbarn presents the new M-Tray® which has been further improved to make sedum roofs easier to install with less disruption to both the plants and the structure. M-Tray® is also designed to give a more seamless, verdant finish and an instant green roof.

Wallbarn is at the forefront of developments in the green roofing sector and has always provided products that combine top-quality ingredients with user-friendly, hassle-free maintenance. The purpose of M-Tray® is to enhance rooftop living

Wallbarn can advise and assist on all aspects of scoping, installing and maintaining your green roof project.

Just pick up the phone, ask a question using the live chat facility on this site or send us an email at info@wallbarn.com and we’ll get back to you next working day at the latest.