Early Engagement During Blue and Green Roof Construction Essential
Sourced from Specification Online
Following Mayor of London Sadiq Khan's pledge to increase the number of green roofs in his re-election manifesto, architects, engineers and contractors are being urged to ensure designs meet both performance needs and British standards.
Urban greening projects are expected to increase across the UK, following changes to local and national planning policies.
One of the key challenges in constructing blue/green roofs, according to ACO Building Drainage, is meeting the needs of the Building Regulations, required standards – BS EN 12056-3:2000 and BS6229: 2018 – and achieving effective rainwater retention.
Currently, as blue/green roofs are flat, they are required to meet the British standards for gravity drainage on flat roofs. However, while traditional flat roofs are designed for water to quickly drain in the event of heavy rainfall, a blue/green roof retains water for 24 hours or more meaning the primary drainage functions are not the same. As such, there is increased risk of flooding if attenuation systems are incorrectly specified and not maintained.
From the Living Architecture Monitor
