Swiss practice Conen Sigl creates humane apartment building in Dübendorf

Approaching the new Westhof apartment building in Hochbord, a short tram ride from the centre of Zürich, its dog-like head turns towards the path as if nodding a welcome. It’s a characteristically friendly gesture in an 87-home scheme whose design is sensitive both to the needs of residents and its setting in a district where large-scale industrial and agricultural buildings are rapidly giving way to high-density housing.

It was developed by a not-for-profit cooperative in collaboration with the landowner, a retired piano teacher who grew up in a plant nursery on the site. Zurich practice Conen Sigl – led by Maria Conen and Raoul Sigl – won the project through a competition; the win attributed to the level of care the architects demonstrated in their approach to the existing site. The design is based on meticulous observation of its character, history and ecology and Conen and Sigl’s belief that any new building must be of outstanding quality to justify the necessary demolition.

They are young and energetic and speak with optimism about how an intelligent and humane approach to housing design can make the city a better place. Their building shows a level of care and ambition that is all too rarely seen in the UK.

The continuous linear building is wrapped around a courtyard and comprises three parts: a four-storey ‘head’; a large nine-storey main block; and a three-storey wing that adjusts to the site’s irregular geometry and protects the courtyard from the noise of passing trains. The long courtyard is open at the southern end where a delicate galvanised steel staircase completes a circular rooftop route across a series of terraces.

On the roof of the lower wing, gardens are set under a galvanised steel pergola reminiscent of commercial greenhouses. Bird boxes are integrated into the ventilation towers that punctuate the structure. The route is enriched by sculptures by Swiss artists Andres Lutz and Anders Guggisberg, who carefully documented the found conditions of the existing site in a film that forms part of an installation in one of several communal rooms within the building.

At ground level there are seven commercial spaces and workshops strategically located around the courtyard, close to entrances and on corners. The three-storey wing contains a series of large apartments designed for sharers, with four or five self-contained bedrooms around a generous shared living room and kitchen.

The tallest part of the building steps back from the courtyard at the fourth floor to complete the terrace that forms part of the rooftop landscape. From this terrace it is possible to call down to children or friends playing or passing the time in the courtyard, ensuring that the large building remains connected to life at the centre of the scheme.

The nine-storey block has a clear spatial idea underlying its plan. The eastern side is divided into small cellular rooms for sleeping and washing while the western half – overlooking the courtyard – contains the larger living rooms and kitchens. Four vertical cores provide access to two apartments on each floor. In the upper part, where the plan is narrower, the cores are expressed externally on the courtyard side – a series of slender ‘towers’ sitting on a wide base where the letterboxes and entrances are sheltered beneath a generous canopy. Together with other simple formal adjustments and a palette of ordinary low-cost materials, it’s one of the sophisticated and nuanced ways in which Conen Sigl has introduced rhythm, repetition, texture and depth to the architecture.

The building is clad in overlapping profiled fibre cement boards in two colours, arranged vertically so that grey-green panels form distinct figures against a background of light grey, contributing to the impression of an assemblage of elements and preventing the envelope from appearing as a continuous profiled skin. Balconies spanning the expressed cores are clad in a horizontal strip of the same profiled material, paired with galvanised steel handrails and vertical elements that support projecting awnings for summer shading.

The rhythms and realities of everyday life are also handled with sincerity and incorporated into the fabric of the project, in spatial and material details executed with a sense of lightness and obvious care for the inhabitants. Inside the entrances, the walls and soffits are applied with blocks of black, white and blue paint, galvanised steel, mirror and wood-wool. These elements, composed with a confident, graphic sensibility alongside black doors and handrails, timber benches and linear white light fittings, add a sense of generosity and decorum to shared spaces of arrival and departure.

The spaces feel slightly unfinished, anticipating the marks and traces of domestic life and social activity. Other public parts of the building were also left incomplete with a portion of the budget held in reserve to fund a series of resident-led projects to finish it. These include a productive garden, play facilities and adaptations of the communal rooms which occupy strategic positions in relation to the courtyard, roof terraces and circulation.

Looking back at Conen Sigl’s earliest competition material, it’s interesting to see that all of these distinctive characteristics of the project were present from the outset, captured in a series of precise handmade perspectives and physical models. The clarity with which the building was conceived and communicated has been carefully translated into a notably civilised, pleasurable place to live. The building offers evidence of a society engaged in a lively and sophisticated architectural discussion about how we live together, balancing issues of privacy against those of urbanity, exploring architectural forms for collective life, emphasising spaces of encounter, and embracing an incompleteness that anticipates the informed agency of future residents.

Alex Gore is co-founder of Pricegore whose recent work includes the renovation of a building for arts organisation Primary and the reworking of a modernist house in Chelsea.