The 2010 Flood and Water Management Act will soon make sustainable drainage systems (SUDS) effectively mandatory for all new buildings. Then, connection to public surface-water drains will only be allowed for approved SUDS schemes. As an important SUDS technique, living roofs will play a major role in satisfying these requirements – particularly in dense, urban environments where land is not available for other SUDS devices.
Planted green roofs at the head of the SUDS ‘management train’ can retain anything between 40% and 100% of rainwater, while delaying runoff and removing pollutants from the remainder. But there is more to living roofs than just planting, with planning policy and other demands for usable space requiring both soft and hard landscaping features. For example, planning policy for London includes a ‘preferred standard’ of: “at least 25 per cent of the total roof space … accessible to residents and/or workers”. Clearly, there is a case for incorporating areas of firm, level, well-drained and non-slip paving to enable safe, simple access for all – but this also needs to incorporate SUDS.
This growing complexity of requirements demands a broader, holistic approach to both design and installation of living roofs. Cityroofs has adopted this ‘elevated landscapes’ approach and works closely with designers and developers on comprehensive solutions including all the elements needed for complete living roofs, terraces, podium decks, promenades, balconies and living facades.