Green roofs perk up blocks of flats

11.1.2017
Fruit trees will soon be growing on the roof of a block of flats in Helsinki’s Jätkäsaari. Both plants and inhabitants will get their own balconies. The unique cooperation project has been developed by TA-Yhtiöt and the University of Helsinki.

TA-Yhtiöt, a company that specialises in right-of-residence flats, is building a completely new kind of block of flats in Helsinki’s Jätkäsaari. The project uses new types of urban construction to bring living nature into solid structures.  The company began its research cooperation with the University’s green roof researchers at the planning stages for the new building in 2011. The construction is scheduled to be completed in autumn 2017.

The group, consisting of researchers, landscape consultants, architects and engineers, has developed a new concept which is intended to mitigate the floods and runoff from heavy rains, dampen noise, create communities and bring Finnish nature into the city.

A multidisciplinary research team

TA-Yhtiöt wants to be an example of the urban planning of the future. This required multidisciplinary expertise as well as cooperation between the company and the University’s researchers.  The research team from the University of Helsinki featured experts from various fields. The design of the new building concept required skills in botany, zoology, hydrology, environmental psychology, aesthetics, microbiology and sociology.

The end result is a house with a significant amount of vegetation. Humans and plants have their own balconies, but also shared spaces.

The construction of plant structures, such as green roofs and walls have been previously studied on a smaller scale. The balconies and balcony boxes of the building, scheduled for completion in autumn 2017, provide a research setting of an unprecedented scale. The selected plants, their growing media and watering systems will be put to a rigorous test. Located in Jätkäsaari, by the sea, the building will be swept by storm winds and the roof will have no protection from sunshine in the summer. The researchers will monitor the plants to see how they fare in the environment created for them.

Heritage plants on the roof

The expertise of the University’s botanists was especially needed in selecting the plants. The ambitious nature lovers were not content with the options available in commercial gardens, but wanted to promote full biodiversity in the city, sowing indigenous Finnish flowers and planting heirloom varieties on the roof.

The plant scientists also provided useful information for their corporate partners. For example, they taught all members of the group to use the Nobanis database, which can determine which plants can be safely imported into Finland and which can pose a threat to the native ecosystem.

The roof of the Jätkäsaari building will feature plants that will benefit the inhabitants, such as berry bushes and even a slow-growing apple tree. To ensure a plentiful berry crop on the sauna terrace, an oasis will be built nearby to attract butterflies and other pollinators.

- “This project is fascinating, but we have had to work very hard for it,” says Docent Susanna Lehvävirta, the head of the research team, from the University of Helsinki’s Faculty of Biological and Environmental Sciences.

The project will keep producing new information for at least the next ten years. The best practices will be passed on by the pioneers.

More about the subject: Health