Jens Kerstan, Senator for the Environment, inaugurated Wednesday (July 13th) the first, 500-square metre green roof on Streit’s Haus on Jungfernstieg. Kerstan said: “The increasing density of buildings in our city makes green roofs an attractive alternative and creates habitats for plants and animals at the same time. At the moment, Hamburg has around 6,300 roofs with 124 hectares of greenery. The city aims to have another 1 million square metres of “green roofs” by 2020.
Protection from heavy rain
Green roofs retain water after thunderstorms and heavy rain. The pressure on the sewage system is reduced as water flows off at a slower rate. The Environmental Authority believes green roofs help adjust to climate change and increasingly heavier rainfalls. On June 23, a storm over Hamburg.
Subsidies for firms
Since 2014, Hamburg has added 44 hectares to the city’s existing green roofs. To boost this development, the Environmental Authority grants maximum subsidies of 30-60 per cent of the production costs, which do not have to be repaid, to private persons and firms. The basic funding starts at EUR 14 per square metre and can go to EUR 50,000 maximum per building. The funds are for green rooftops on the top floors of residential and non-residential buildings, which are carried out on a voluntary basis and are not required by law. The Hamburgische Investitions- und Förderbank can give advice on the funding.