Evergreen innovation: Even in the cold, our green facade looks cool
Northern European climates pose a big challenge to integrating green facades in architecture. Life leaves ‘living’ walls as temperatures drop; we see green facades change from green to brown, taking away the beauty of a ‘green wall’ and its effect on local flora and fauna.
As a striking contrast to many existing green facade solutions that are add-on components installed onto existing structures, we have designed a new type of biophilic facade element that integrates with the building design. With both its aesthetic and structural features, the new facade element opens the door to new ways of designing with vertical nature in architecture.
“We wanted to design a self-sustaining facade which provides pedestrians with a connection to wild nature and increases local biodiversity, while also ensuring that the structure behind is protected,” says Jakob Strømann-Andersen, Director of Sustainability and Innovation. “This facade element is inherently green. It’s not something we add once the building is complete.”
The Paradox of Beauty and Biodiversity
Our green facade solution can adapt to different kinds of architecture and facade expressions while functioning as an integral building component. The boxed facade is a modular system and is designed in Corten steel perforated on the front. Seeds are sown and plants are grown in the facade off-site so that they appear green and lush when installed. That also means that the plants can wilt during winter without compromising the aesthetics of the facade.
The first project to integrate the facade will be in Nordø, in Copenhagen’s Northern Harbor district. For this microclimate, which includes harsh winds, cold temperatures, and salt from the sea, the team has selected plants with two very different sets of qualities; some plants look beautiful 365 days a year but are naturally low in biodiversity, whereas others are hosts to as many as 132 different native insects, albeit not very pretty on the eye during colder months. In that way, the facade accommodates the need for both an aesthetically appealing solution and one that promotes biodiversity.
“The biggest threat to nature is the lack of space, and every day, plant and animal species disappear. By utilizing the city’s vertical space, flora and fauna can be significantly increased, but we have to do it in a way that accommodates local climates and native species. A building in Denmark can never look as lush as one in Singapore. So instead of trying to reach something unattainable, we’ve designed a facade that adapts to the dynamic of the changing seasons in Scandinavia,” explains Jakob Strømann-Andersen.
The facade incorporates a controlled hydraulic buffer capacity, which collects rainwater from the roof. This ensures that water is constantly accessible to the plants and adds robustness in operation.
Harvesting Carbon while in Operation
Our partner on the project, BG Byggros, has implemented procedures that ensure continuous CO2 absorption. By utilizing an annual harvest of plant mass and biomass as part of the operation, contrary to normal where plant compost and CO2 are released, they will instead store it by converting it to biochar via pyrolysis. The biochar can then be used in growth media as a precious nutrient buffer for plant growth.
The facade in Nordø, will be equipped with sensors that will measure the facade’s impact on noise and temperatures at street level.
“Our simulations at Nordø show that we can expect a 15% noise reduction at street level, and due to the evaporating and heat absorbing abilities of plants, the facade will help to reduce the temperature in the street during summer,” explains Jakob Strømann-Andersen.
Developed by PFA, Nordø is a mixed-use development in Copenhagen’s Northern Harbor neighborhood. The facade will make its debut on the office building “Porten”, planned for completion in 2023.
The green facade is designed in collaboration with BG Byggros and Komproment and supported by the Danish Ministry of Environment.
