In the context of our work here at Pritchard and Pritchard our work with Blue Roofing systems provides the perfect solution to managing water in the urban environment.
Incorporating a blue roof system for your green roof project enables water retention on rooftops, reducing the volume and speed of rainwater runoff. This reduces
flooding in urban areas and eases the strain on sometimes antiquated sewerage systems.
What are the benefits of Blue Roof systems and why should you specify them?
1. Stormwater management: Blue Roof Systems help control the flow of stormwater, preventing overwhelming of drainage systems during heavy rainfall. By slowing down the runoff, these systems reduce the risk of flooding and erosion in urban areas.
2. Water conservation: Blue roofs can be connected to rainwater harvesting solutions – this stored water is perfect for irrigation of landscapes, cooling systems – even for flushing toilets. This reduces the demand for fresh water from traditional sources, promoting water conversation. This makes blue roofs an intelligent choice for property developers seeking to maximise the sustainability of their buildings and landscapes.
3. Mitigation of the Urban Heat Island Effect: Blue Roofs often incorporate reflective or cool roof materials, mitigating the urban heat island effect. By reflecting more sunlight and absorbing less heat, these roofs contribute to lower ambient temperatures, which can indirectly impact water conservation by reducing the need for energy-intensive cooling systems. The
addition of planting further enhances their benefits and supports biodiversity net gain legislation in the UK.
4. Extended Lifespan of Stormwater Infrastructure: By managing stormwater at the source, Blue Roofs can help extend the lifespan of downstream stormwater infrastructure such as pipes and culverts. This can result in cost savings for councils and reduce the environmental impact associated with the construction and maintenance of these systems, not to mention the retrospective clear up created by stormwater damage.
5. Green Building Certification: Blue roofs can contribute to sustainability goals and support green building accreditations such as BREEAM, WELL and Biodiversity Net Gain.
6. Improved energy consumption: Living roof systems including blue roofs contribute to improved insulation in buildings where they are specified, reducing heating bills in the winter and air conditioning to cool in the summer.
Wimbledon Grounds Blue Roof a benchmark example of incorporating blue roofs
Wimbledon Grounds, Galliard Homes’ residential development of 583 apartments is ground-breaking in the UK for its large-scale use of the triumvirate of sustainable roofing technologies, blue, green and solar.
– All 26 roofs and four landscaped podiums are blue roofs, or sustainableurban drainage systems (SuDS).
– With a total area of 14,000 square metres, this is one of the largest blue roofing projects ever seen in London.
– All 26 blue roofs are also green roofs have living roofs, installed above the blue roofs, which are seeded with a mix of native wildflowers, sedum and
grasses.
– On 15 of these blue-green roofs, Galliard has installed farms of solar panels to generate electricity for the complex.
The Wimbledon Grounds blue roofing system works on a cascade system. According to details shared by ZinCo Green Roof Systems, each roof stores up to 55 litres/metre2 of storm water in a reservoir. This is gradually released by a flow controller over 12-24 hours to the larger reservoir in the 4 podiums, which holds 60l/m2 of storm water, from where it is slowly released into the urban drainage system.
This capacity at Wimbledon Grounds allows the blue roof reservoirs to store 40% more rain water than is calculated to fall in the ‘one in 100 year’ storm.
