Real-time display of
                green roof run-off
THE MAPPING ROOF The Mappin Roof has been insitu since the end of 2006 collecting data. As the pilot test roof, it has been an invaluable asset in ascertaining green roof performance as well as designing further research.
Stovin, VR, Dunnett, N, Hallam, A, Green Roofs – getting sustainable drainage off the ground, 6th International Conference of Sustainable Techniques and Strategies in Urban Water Management (Novatech 2007), Lyon, France, 25-28 June 2007.
The Hadfield Roofs are 9 new green roofs that form a comparative study investigating the effects of roof vegetation and substrate on roof performance. They have been collecting data since mid 2009, and a sample of this new data is available for viewing. THE HADFIELD ROOFS

Background

Green roofs are roofs that have been especially fitted or designed to support a shallow-growing vegetation such as sedem or meadow grass on the roof's surface. Green roofs emulate a natural environment on the roof's surface, attenuating and retaining rainfall. This categorizes them as a Sustainable Urban Drainage System, effectively reducing the impermeable area of a catchment.

As population density increases, and urban impermeable cover increases, sewer designs of the last 50 and 100 years are becoming inadequate for normal flows. Climate change compounds this problem, resulting in increased flood volumes and frequencies. With the average lifetime of a given section of sewer in the UK being 1,000 years, any effort to alleviate load on the network should be investigated.

Green roofs will decrease the amount of water that needs to be treated at the sewerage treatment works, as well as potentially improving the run-off quality. This will reduce load on the entire system and result in lower costs and cleaner water spilling into rivers when the network does overflow. In networks where stormwater does not flow into the sewer, local flooding will be reduced.

The data presented on this website in the format of graphs help to illustrate the time delay and retention or the difference between rainfall and run-off, caused by the roof. This is influenced by a variety of factors such as humidity, temperature, the last time it rained, as well as roof configuration.

More information is available at The Green Roof Centre.