Grass and honeysuckles are to cover the roofs of Copenhagen

Thursday, 08 October 2009 13:58

As part of Copenhagen’s climate plan, all new flat roofs are to be green. Therefore, every time a square metre of land is removed, it is re-established on the top of a house. Green roofs are part of Copenhagen’s ambitious climate plan which is to make Copenhagen CO2 neutral by the year 2025.

Dorthe Rømø, who is the project manager of the grassroots organization Grønne Tage (Green Roofs) (http://www.gronnetage.dk/), says that people need to learn to think about roofs as a fifth façade and take advantage of the unutilized areas on top of their buildings.
Green roofs have many advantages:

• They can absorb 60-80 per cent of rain water falling on the roof, thereby diminishing the burden on the sewer system.
• They isolate, thereby saving energy for heating the house during winter time and cooling during summer time.
• They function as sound insulation.
• They diminish the urban heat island effect i.e. the phenomenon that the temperature in the city is higher because of the many dark surfaces of roads and roofs.
• The durability of the roof is prolonged to approximately the double because the green protects against UV radiation.

The roof gardens furthermore serve to give people an idea of what sustainability is - which is also part of the Copenhagen climate plan: to increase knowledge among the citizens.

In several countries roof gardens are already used in many different ways, and scientists are still actively searching for new ways to develop the best green roofs for different purposes. In Zürich, an old roof has become the refuge for nine species of orchids that disappeared when the land was cultivated, in Singapore a hospital has made a vegetable garden on the roof, providing healthy food for the patients, and the roof of Chicago city hall is decorated by a big luxuriant garden. Furthermore, in several places, making new flat roofs green has become a legal requirement. In Berlin, Chicago, Cologne, Portland and Münster you will receive a reduction in your drainage charge if you establish a green roof.

In Copenhagen, establishing green roofs will not become a legal requirement for yet another four years, as the climate plan first need to be incorporated into the plan of the local municipality. However, more and more architects are taking green roofs into consideration when designing new buildings and with 7,200 square metres, the new building of Public Records makes up the largest roof garden in Copenhagen so far.

For more information on green roofs:
http://www.igra-world.com/index.php