In Zurich, the Facade of an Eco-Friendly Home Extension Looks Like an Eyeball

Houses We Love: Every day we feature a remarkable space submitted by our community of architects, designers, builders, and homeowners. Have one to share? Post it here.

Project Details:

Location: Zurich, Switzerland

Architect: Studio Anna Jach GmbH 

Footprint: 1,668 square feet

Builder: Holzbau Oberholzer GmbH

Structural Engineer: Ibeg

Landscape Design: Boesch Gartenbau

Cabinetry Design: Schreinerarbeiten und Mehr

Photographer: Alexandre Kapellos / @alexandrekapellos

From the Architect: "The project involves an extension of the entry area, the addition of a new guest bathroom, a two-story library designed to accommodate 500 books, featuring a swing for the youngest child, a yoga and meditation room, a child's bedroom, and a rooftop terrace. 

"The site is located on a very narrow and highly frequented street, presenting challenges such as limited parking availability for contractors. Additionally, the client required a swift construction process in order to move back into the property as soon as possible. 

"Sustainability was a central consideration in the construction process. A significant reduction in the carbon footprint was achieved through the use of locally sourced wood and insulation materials, specifically blown-in cellulose. The selection of local contractors and materials minimized transportation distances. Excavated earth was repurposed to create a rammed-earth sitting bench in the garden. The installation of solar panels on the rooftop, along with a heat pump, ensures the provision of electrical energy and hot water. The building's insulation reduced heating costs by 50 percent. Internally, wooden panels were left untreated with additional renders, serving as the final finishing surface. This approach promotes natural humidity exchange, creates a pleasant indoor climate, and retains the natural scent of fresh pine wood. No artificial chemical treatments were used for internal wall protection; instead, the surfaces were treated with natural flax oil combined with five percent white mineral paint to prevent yellowing over time.

"The construction method involved the use of prefabricated, sandwich-like insulated pine wood panels, which were assembled on-site by a team of four using a mobile crane within five hours. The exterior was finished and protected with vertical wood planks. Groove and tongue connections were utilized, reducing the need for screws and bolts. The prefabrication of the walls was carried out using modern CNC-cut technology in an assembly hall located 23 miles from the construction site.

"The building’s facade features a programmed 3D shadow relief created by the artists Drzach & Suchy. CNC wave-cut vertical facade planks cast a shadow of a closed eye in the morning, which gradually opens throughout the day, imparting a "living" effect to the exterior skin of the building and fostering interaction with the surroundings. Additionally, a blown-up steel canopy was designed by the artist and product designer Oskar Zieta."