The European residential high-rise boom has a green twist these days. Magnus Kaminiarz & Cie unanimously won a top design award this spring for a remarkable apartment tower at the Skyline Plaza complex in Frankfurt. Kaminiarz will produce not only the tallest residential building in Germany—-50+ floors, overreaching Frank Gehry’s planned 150-meter building in Berlin by about 10 meters—but also a bold example of Aktivhaus (“Active House”) construction.
An Active House not only heats and powers itself. It also produces extra energy. While low-energy passive solar designs depend on energy conservation, insulation, and heat exchange, active houses typically capture more energy than their occupants need. However, they can also require much higher initial investment and more complex maintenance to achieve their celebrated energy efficiencies.
As you can see from the photo, the facade of the Frankfurt tower is 100% glass. Each Aktivhaus living unit has triple-insulated glazing. This maximizes daylight and the visual connection to outside surroundings. It also uses free sun power for winter heating. Balconies shade the facades during summer and provide windscreens. Radiant surfaces maximize thermal comfort in each room, supplemented by low-energy district heating and an absorption chiller.
While each living unit has natural ventilation, air supply elements individually controlled and equipped with convectors to preheat the supplied air can supplement when needed. Kitchens and bathrooms use air extraction, and the exhaust system has centralized heat recovery used for applications like domestic hot water preheating.
Every balcony on the Frankfurt Aktivhaus high-rise will carry PV modules to provide energy to operate the building. There are 340 apartments in all: approximately 30% small, 55% classic three-and four-bedrooms, and 15% deluxe. All have access to an aboveground five-story car parking lot.
Connoisseurs have hailed the Skyline Plaza Tower, which somewhat resembles London’s Canaletto Tower, as “an amazing and unusual design,” “so much better than anything else built and proposed in Frankfurt in recent years,” a building that “has that flavourful retro vibe to it, too.”