The Haus am Weinberg in Stuttgart by UNStudio is the latest in a species of private houses by the practice including the Möbius House in Het Gooi in the Netherlands (1998) and VilLA NM in upstate New York (2007). In its bespoke experimentalism, it also relates to their pavilion architecture for the Chicago Millenium Park and the Venice Biennale of 2008. With a constant focus on experimentation throughout the 50 buildings completed to date, UNStudio’s work effortlessly combines a number of gestures that create flexible spaces. “Architecture is so stiff, so difficult to adjust”, says co-founder Ben van Berkel, but with productive, double-curved surfaces, he feels it can appear “far more reductive, and let complexity in”. That contradiction in terms relates architecture to nature through the exploration of the discipline’s deeper science. On the outskirts of Stuttgart, the context of the latest villa is both attractively rural and suburban, with views of the stepped terraces of a hillside vineyard on one side and views of the city on the other. “The location was perfect”, says van Berkel. He picked up a lot of ideas about landscape that can be seen in the structure of the house as you move through it, “like looking up the hill as you ascend the staircase”. The villa is certainly a bit surreal, plays with the owners’ ambitions for their domestic space, is part of the landscape and a form of sculpture. Its geometries deliberately include some “painful qualities”, justified because, like all UNStudio’s buildings, it is a virtually column-free space and contains many of van Berkel’s other creative preoccupations. A central twisting structural element supports the main staircase, organising the main spatial flows through the two storey house and structuring views out to the surrounding landscape. “The building’s load bearing concrete structure is reduced to the minimum”, says van Berkel, “underlining the idea of a built sculpture”. It was challenging for them. The roof and slabs are supported by four elements, the elevator shaft, two pillars and one inner column. Long span cantilevers internally cause very high horizontal forces in the lateral system, ones that could be expected for a 15 storey, rather than a 3 storey building. As a result, sophisticated 3d analysis of the load path combined with carefully reinforcement layout was mandatory. Besides this main system, a slender hanging steel structure supports the two storey façade of the dining room, allowing for a glazed, column free corner which can slide open. This structure gives the appearance of walls rising across its south facing glass curtain windows, joining a lifted up roof facing the hill, with the north-west side like a winking eye. Entering at the south side, where the guest suite, wine cellar and garage are located, the visitor crosses the entrance hall and ascends a diagonal staircase to the first floor where the first view from the twist is angled towards the north west and vineyard hill. Sliding panes open up, dissolving further the boundaries between inside and outside. The second view is from the living room, extended via a glazed corner, and then the staircase twists up to a gallery space on the second floor, with a small library. Two further views planned here from the twist open up from the master bedroom and wellness areas, of the north-east, south-east and whole east side of the house, a zone with a fully glazed corridor between the two spaces. The gallery appears to float above the double height kitchen/dining room. A white kitchen table extends out on to the garden terrace. Adding to the flowing spatiality, the natural limestone floors and fireplace, white clay stucco walls with reflective mica create a huge sense of lightness. This area of the villa, is spatially mixed in atmosphere and quality, and includes a room where one of the owners has his grand piano and hunting trophies, fitted with semi-relief acoustic wooden paneled walls. “Their patterns extend the drama and dreaminess of his character”, says van Berkel. The volume and roofline of the villa respond to the sloping landscape of the site: on the lower south side, the roof relates to the geometry of a traditional pitched roof, while on the north side, it follows the line of the vineyard hill. The villa achieves a “stereovisual spatial effect” - an almost virtual replacement of the surrounding views of the vineyard landscape can be experienced as you move through and up in the house. “It becomes a kind of telescope but also echoes the landscape”, says van Berkel. “Sometimes I’m into material colour, but here I was interested in a traditional modernist colour”, says van Berkel. “I don’t like to emphasise the architecture itself, but what it wants to be. It likes to disappear, becoming a background to people and landscape”. VilLA NM is more related to the colour of the landscape, while in the Haus am Weinberg, “it was a deliberate choice to have one colour to emphasise the spatial quality of the design”. Van Berkel is very interested in “how rhythmic elements could create a certain complex calmness, by movements and repetition, which could be similar to music”. The operativity of the double curved surface - whether used for orientation, infrastructure distribution (at the Central Hall of the Arnhem transport hub or the Music Theatre, Graz, 2008) or helping parallax effects - “it’s important to bring in a discipline in angles of surfaces. A linear box can create a serenity”, but he is concerned with “rhythmic qualities while you move”.

Lucy Bullivant