At-home solar generation meets modernist design

Q&A with German Architect Stefan Behnisch

Le toit solaire primé de la résidence Haus B en Suisse

In 2016, German architectural duo Katja Knaus and Benedikt Bosch of Yonder – Architektur und Design imagined an Energy-Plus home. The result, Haus B, features a building-integrated solar roof to reduce material waste and elevate the home’s ambitious design.

House B, an ambitious design

Built into a steep hillside overlooking Stuttgart’s lush river valley, Haus B boasts impressive panoramic views from every level. Yonder – Architektur und Design, the firm responsible for the home’s latest renovation, designed a residence decidedly fit for an architect. The home, originally built in the 1950s, is owned by fellow architect Stefan Behnisch of Behnisch Architekten. Completed in 2016, the residence would go on in 2017 to win the Wood Design and Building Award.

A residential building intended for the production of solar energy

Aside from its sleek, finished wooden interior, the home is characterized by its collection of sustainable features: electric vehicle charging stations, geothermal wells and heat-pumps, and battery storage. Of these features, the building’s SunStyle solar roof is the most visible, producing 3,300 kilowatt-hours of energy, enough to offset the majority of the building’s overall usage. Five years after construction ended, the SunStyle team recently had the opportunity to catch up with Mr. Behnisch.

Haus B, la maison d’architecte à énergie positive avec sa toiture SunStyle

Interview with Stefan Behnisch

SunStyle: What led you to choose a SunStyle roof for Haus B?

Behnisch: We wanted a photovoltaic (PV) roof. Normally, PV panels are an added element. I don’t like this. I consider it a waste of resources and architecturally unpleasant. I wanted a roof where the water protecting layer is the PV with no added layer. And at that time (2016), Sunstyle was the only good solar roof system on the market. It can be more economical if you use the PV as roof covering and don’t double up the elements.

SunStyle: What do you think of the SunStyle roof today?

Behnisch: It’s perfect, we are using [SunStyle] in other projects, as well. Right now, we are finishing a school building for the Steiner School in Stuttgart with SunStyle shingles. This is our preferred solution for roofs.

SunStyle: What recommendations would you share with someone considering a solar roof?

Behnisch: Go for it, it’s a no-brainer. And make sure you don’t build a roof and on top of it another PV layer. It’s a waste of materials, money and embedded energy. I would also make sure the battery is large enough or even better, have a small one and a bidirectional electric car as overflow storage.

Editor’s Note: The interview has been edited for length and clarity. Photos courtesy of Brigida Gonzàlez.