Statistical Proof that Green Roofs Save energy and Money

We've been thinking about experimenting with a green roof here at Everythings Gone Green Towers for quite some time now. Our house roof is far too steeply pitched but our garage, in the back garden, is an ideal candidate for some green roof experimentation.

Green roofs, which can be partially or completely covered in vegetation, are an excellent way to reduce your carbon footprint. They can be installed on existing properties and new builds and provide so many positives.

The Sedum green roof is much like turf, and can be rolled out quickly and easily. Sedum is a large genus of around 400 species of succulents, so they are virtually maintenance-free because they soak up a lot of moisture.

Beyond sedum green roofs, your imagination and the structure of the building, are the only limits with some green roofs having ponds and trees!

New research from energy and environmental consultancy, Atmos Consulting, says that green roofs are definitely beneficial. Whilst we're looking at a domestic green roof here in Farnborough, Atmos Consulting have been looking at the viability and impact of green roofs on businesses. They say that green roofs help businesses to achieve their sustainability targets and that the "payback times" are getting shorter.

The benefits of green roofs, according to research, are numerous. Atmos say that green roofs are:

  • Heat Insulators  Green roofs insulate buildings and thereby cut energy costs. As an example, a recent study has shown that green roofs save 2 litres of fuel oil per square metre.
  • Cool Insulators  By insulating a building in the summertime it has been seen that heat absorption of a building can be reduced by as much as 84% - By keeping the temperature down the need for cooling is reduced, thereby cutting the use of air conditioning and encouraging further cost savings.
  • Durable: Green roofs are expected to last between 2.5 and 3.5 times longer than roofs made from "standard materials". Again, the cost of repair and replacement of a regular roof is much reduced over the same lifetime.
  • Pollution Reducers: A square metre of grass can remove 0.2kg of particulates per annum. They also trap chmicals and pollutants that would otherwise go straight to drainage systems. (If water companies had to treat waste water less would water bills go down?)
  • Run-off Reducers: A green roof will retain as much as 90-100% of of the very critical first hour of heavy/storm rainfall and around 50-60% of run-off over the period of a year. Again, drainage costs are reduced and this aids the management of flood prevention.
  •  Wildlife Habitats: Insects, birds and other wildlife love green roofs and so they are a boon to increasing local ecology and biodiversity.
  • Sustainable: Government-set sustainability targets can be partially met by installing a green roof. Of course, there are many other factors but green roofs play a contributory role in meeting BREEAM assesments for instance.
  • PR Generators: Installing a green roof can generate lots of positive publicity. Local and national press, trade magazines, environmental, energy and green publications and organisations will be happy to promote further the news of green roofs in domestic and commercial applications.

Vicky Ward, Ecological Consultant at Atmos, is positive about the green roof revolution, saying;

“Green roofs have long been popular with companies that want to better the environment, and go a long way to achieving sustainability targets.

“Thanks to developing technology the payback periods are becoming much shorter, making green roofs a sound financial investment. We urge anyone developing new properties or renovating existing ones to consider them.”

If you're thinking of doing your own green roof project we highly recommend you take a look at the book Small Green Roofs: Low-Tech Options for Homeowners, co-written by Dusty Gedge, among others, who you can follow on twitter, handle @greenroofsuk.