As part of the Museum of London's massive refurbishment, they have begun to install an ambitious green roof on the top of the building. This will be a long-term research and demonstration project, rather than the sexy public spaces that we have seen on other buildings.
By having a number of different habitats, it will show the diversity that green roofs can have. There are plans for wildflower meadows, wetland areas, bluebell wood and planted walls. All using recycled materials from the existing roof.
By planting the green roof, the Museum reckoned that they could extend the life of the roof, avoid flash flooding and provide a valuable demonstration project for other buildings. An energy savings of 10% a year was assumed, as well, it would increase the green space in the City of London (the financial district).
It has been a massive job. All of the pavers and insulation from the old roof are being removed and being replaced with the Bauder waterproofing and green roof system.
One of the volunteers who helped out has written of the experience. The landscaped wildflower habitat on the roof area was planted in low banks to provide a sheltered area for the flowers. A mixture of Bauder green roof substrate and sharp sand was used, along with the existing shingle ballast from the old roof covering. It is hoped that the sand banks will encourage ground dwelling solitary bees. More than ten varieties of wild flowers were manually plug planted into the banks.
Hedges are being planted along the elevated sides of the roof. These will act as wind breakers as well as insect habitats.
There are new herb plantings, just put in this summer, which are already flourishing. An area for alpine plantings is also being installed.
Photo: B. Alter
This is the site of the future bluebell wood. The shady area will have grasses and ground covers. Optimism is a necessity in this business.
Another aspect that is being examined is planning for flash floods. These happen during the summer when there is a sudden rainfall. Studies of rainwater run-off from different green roofs are being researched. Retaining rainwater helps reduce flash flooding, which has been a big problem in central London in recent years, causing several tube stations to flood.
Photo: B. Alter
The courtyard that is open to the public has also been refurbished and turned into a little green garden of Eden. There is a thriving hive which is part of a City of London wide project to install more hives on roofs in that area.
New plants in the courtyard such as Verbena and a wild flower meadow and potted herbs are bee-friendly. Indeed, the first honey was just bottled last month and was delicious. The courtyard is rather sterile, but designed to be flexible and easily changed, to fit in with exhibitions in the galleries.