Environmental impacts » Case study » Wildlife

Green roof takes root…

London’s largest single membrane green roof – the first on a railway building – was installed by Tube Lines in 2006. It is bedding in so well that we will be installing one on our new Stratford train crew accommodation building, too.

The green roof tops the new £14m Northern line control centre which will house state-of-the-art signalling equipment. Construction work began in May 2005 and is on schedule for completion in August 2007.

Because the site backs on to protected woodlands, the building needed to be as unobtrusive as possible. Following discussions with the local community, the Corporation of London and the local authority, an environmentally-sensitive, single-storey design was agreed including a wooden acoustic fence and coloured cladding to blend with the surroundings as well as the green roof.

“The roof has bedded in really well, despite last summer’s drought,” comments Project Manager George Mavrias. “It was planted with various species of sedum, selected for their drought resistance, interspersed with indigenous cuttings from local woods to promote local colonisation.

“As well as being practically maintenance-free, it blends in with the woodland, provides additional habitat for local biodiversity, stabilises internal temperatures and acts as a natural soakaway. To date, during intense periods of heavy rain we have not seen a drop of water running off the roof.

“Once the idea of a green roof had been suggested, everyone could see the benefits. It’s good to see that it has been such a success. We are so inspired by it that the company is planning a second green roof on the new Stratford train crew accommodation building.”