Is a Blue Roof the New Green Roof?
We are celebrating #EarthDay 2021 with a look at the benefits of stormwater management roofs and why they play such a valuable role in supporting sustainable cities in the face of extreme climate events.
World Earth Day has been established and celebrated on the 22nd April since 1970 and represents a global movement towards enhancing the world’s natural resources. ‘The theme for Earth Day 2021 is ‘Restore our Earth’ which focuses on natural processes, emerging green technologies and innovative thinking that can restore the worlds ecosystems.’
Green and Blue roofs are not ‘new’, for centuries green roofs of one sort or another have been used to protect buildings to provide both protection and insulation and to create a natural ‘sponge’ to absorb water. What has changed is the ongoing and emerging technologies to enhance our roof top planting more, to use the surface area of a roof to store water safely, to boost clean energy and to provide amenity space & food growing opportunities for urban communities.
Blue roofs are of particular interest in the context of World Earth Day. A blue roof incorporates sustainable drainage (SuDS) which retains water following a downpour and manages how the water is dispersed to prevent overburdening urban drainage systems with the large volumes of water supplied by flash flooding events. The beauty of the Blue Roof is its ability to sit unseen within the construction of a ‘green roof’ as one layer of the roof construction process, the two innovations work hand in hand together to be the optimum urban roofing system.
Our work at one of the largest ‘blue roofs’ in London continues, ‘Wimbledon Grounds’ is a development of 600 new homes in Merton, from Galliard Homes and Catalyst which sets the new high standard for sustainability and certainly sets a benchmark for the use of blue roofs at residential properties. Not only is every green roof at Wimbledon Grounds ‘blue’, but they are also planted with wildflower seeds to enhance biodiversity, some roof sections are further enhanced with solar panels, and additional podium gardens for amenity quite literally make this development a sustainable roofing showcase!
The roofing project being undertaken here consists of 15,967 m2 of blue roof of which 8,860m2 is green roofs. The roof spaces also include solar and native wildflowers. Capable of storing nearly 1 million litres of water it truly is a benchmark roofing project for London and should lead the way for green roofing projects in other major cities throughout the rest of the world.
Installed using products from Zinco, with leading roofing contractor Kingsley who undertook all waterproofing – Pritchard and Pritchard have undertaken all of the green and blue roof installation at this project and look forward to reaching full completion at the end of May 2021.