GRO Chair Mark Harris looks at a new report which provides further evidence of the crucial role roofs can play in mitigating the effects of climate change, with a particular focus on ensuring the long-term success of green and blue roof projects…
A new report from the University of Southampton Energy and Climate Change Division of the School of Engineering, commissioned by the NFRC Charitable Trust, highlights some key steps that specifiers, building owners and home owners can take to use the roof to help mitigate the impacts of climate change.
Whilst the largest roofing trade association in the UK could be expected to promote the contribution roofs can make to managing climate change, the award-winning environmental charity Hubbub also recognises the valuable contribution that roofs can make – so much so that one of its 10 ‘Asks’ in The Greenprint is to ‘Ensure no roof goes unused.’
As the trade association representing the Green, Blue and BioSolar industries, GRO fully endorses the recommendations in the ‘Building resilience of roofing technologies in a changing climate‘ report, and recommends that all roofing system manufacturers look at ways in which to align their product ranges to fully support specifiers in following this direction of travel, so we can improve the built environment. GRO Members are already on this pathway and GRO invites manufacturers, suppliers, contractors and anyone involved in the design, specification, installation and maintenance of these products and systems, that have a positive impact on the built environment, to join us to develop guidance that will help the wider industry adopt climate change mitigation measures.
The report points to a number of roofing “technologies” and ways the sector can contribute to “building the resilience of the built environment to adapt to these changes in our climate”:
• Conventional (consolidated technologies); These are technologies that are consolidated in the market currently in both the residential and non-residential sectors, such as enhanced levels of insulation and improving airtightness.
GRO endorses these and recommends ensuring that every roof is designed to optimise thermal efficiency within the design constraints of the roof, roof terrace or podium.
• Cool (highly reflective coatings); A cool roof is one that is designed to reflect more sunlight and absorb less heat than a conventional roof, typically flat or low sloped. A highly reflective type of paint, sheet covering, tiles or shingles can be used to achieve this.
Green roofs help with the cooling of roofs and the surrounding environment, but GRO accepts that not all roofs are suitable for greening. If you are paving a roof terrace use light coloured paving, ballast or porcelain tiles.
• Green (vegetated); These are ballasted roofs that cover a conventional roof (typically flat) with a waterproofing later, growing medium (soil) and vegetation (plants).
Correctly designed, installed and maintained sedum extensive, wildflower and biodiverse green roof ranges provide self-sustaining plant communities that replicate or replace the natural environment that was there before construction. These roofs enhance both flora and fauna in the local environment, help mitigate pollution, airborne noise, and improve health and wellbeing and provide amenity space.
• Blue (vegetated with enhanced stormwater attenuation capacity); These are roofs that are designed to slow the drainage of rainwater collected above a roof’s waterproof element, unlike conventional roofs which allow rainwater to drain quickly away from the roof.
Blue Roof systems provide roof level attenuation and discharge rate control, meeting the requirements for the London Plan 2021, and they are typically installed beneath a green roof to provide multiple benefits to the built environment and beyond.
View the report at: www.nfrc.co.uk