Haus B

Haus B is a work by Yonder for a well-known, Stuttgart-based family of architects. Before the turn of the century, the family moved into a frequently refurbished 1950s building located on a site with magnificent views of Stuttgart’s basin-shaped valley. Yonder’s task was to renovate and rebuild this existing building.

In an effort to work sustainably, the new construction makes use of the existing house as much as possible. At the same time, the reconstruction more clearly organizes space, better frames the site’s breathtaking views and ensures that the four level building be easily accessible despite being constructed on a site with an extreme slope.

To this end, the building’s roof and ground floor were partly removed and rebuilt in wood. The new construction has an airy, spatious quality, and provides an elevator and a generous roof terrace. Panoramic windows at the newly designed levels afford unimpeded views over Stuttgart and the nearby Teahouse. The building’s open interior has a continuous flow accented by unique architectural spaces, built-in furniture made from oiled walnut and oak and carefully positioned windows. Living in “greenspace,” above the rooftops of the city, is thus experienced spatially through one’s ever-changing point of view. The ground floor and the upper floor are connected to each other by an open staircase flanked by wooden built-ins.

Most importantly, this construction strives to be Energy-Plus and could, in the future, deliver excess energy to the greater power grid. Drilled geothermal wells provide ground water used to heat and cool ceilings and floors. Photovoltaic shingles clad the roof, harvesting energy while serving as a water-resistant roof covering, and a highly insulated façade ensures optimal protection from heat in summer and cold in winter. Electric filling stations facilitate the use of e-mobility.

This award-winning residential complex in Stuttgart (southwest Germany) was completed in 2016 and integrates the SunStyle solar roof into an elegant modernist architecture by Yonder Architecture and Design. Most importantly, the building is a plus-energy building designed to feed surplus energy into the power grid over the long term. Geothermal wells provide groundwater that is used to heat and cool the ceilings and floors. SunStyle solar tiles cover the roof, and a highly insulated facade provides optimal protection from heat in summer and cold in winter. The residence generates 30 kWh/m2 and offsets 59% of the building’s total energy consumption with only 110 m2 of total roof area. Built on a steep hill overlooking the lush river valley of Stuttgart, House B offers impressive panoramic views from all levels.

Focus on the aesthetics
Yonder Architecture and Design teamed up with architect Stefan Behnisch, the owner of House B, to renovate this 1950s residential building. The goal was to combine design and ecology and create a symbiosis. With the SunStyle solar roof, the architects came one step closer to their vision of a house that produces more electricity than it consumes. The home’s solar roof is very noticeable when approached from the top of the hill. Accordingly, an innovative design was needed that respects the exterior aesthetics of the house and blends in with its surroundings. In addition to the elegant finished wooden interior, the house is distinguished by a variety of environmentally friendly features. There are battery storage units that access the collected solar energy in the evening, as well as a charging station to ensure e-mobility. Geothermal wells provide clean heating and cooling.

The advantages of a Sunstyle solar roof
Since the house was completed in 2016, Behnisch has incorporated the SunStyle into other designs, including that of Stuttgart’s Steiner School. The architect now calls the SunStyle solar roof his preferred solution for sustainable roofs. For Behnisch, there are several arguments for this. Clearly, the aesthetics are an important aspect, but so are the cost savings, since the solar tiles are also used as a roof structure, as well as the optimal energy generation provided by the solar roof.