Draped like a curtain

Architect Wouter Hermanns of Amsterdam-based architecture firm Studioninedots describes the development of the facade of the Wisselspoor Utrecht car park as ‘an exceptional process, a joint search for the best solution’. The architects’ idea to clad the parking tower with a wavy curtain of  MD Expanded Metal turned out to be an exploration of the limits of the capricious material.

Studioninedots drew up the masterplan for the Wisselspoor area development in Utrecht together with Delva Landscape. Within this masterplan, the former railroad workshop Werkplaats Wisselspoor remained as a monument to the area's original function. Wouter Hermanns, architect at Studioninedots: ‘Buildings like the former workshop define the character of the area. You want to preserve that.’

Transformation of the industrial building did not prove easy. Wouter: ‘It is a very large building that needed a function and meaning within a context with small houses. The volume was too big for the public programme on that particular part of the site – a place for cultural activities in the neighbourhood. But the building was just too beautiful to demolish.’ The architects found a purpose for the building within the urban masterplan. ‘A parking garage in the middle of the area is a very logical intervention to minimise the number of cars on the street.’

Changing contrasts

‘We wanted to give the car park a special appearance, something alienating within this new living area - like a beacon in the neighbourhood,’ says the architect. ‘We drew a “curtain” around the parking tower in the heart of the building, which created a contrast in the overall image: an enrichment of the existing building with a new addition in a new language.’

The architects looked for a material to make that curtain and to achieve the desired effect and decided on expanded metal. ‘We looked at texture, at transparency and patterns. We studied variations where the curtain was tight at the top and flared at the bottom. That scenario turned out to be a bit too ambitious for a car park budget. In the end, we drew an irregularly waved curtain made of expanded metal. The next step was finding companies that could make it.’

Concave waves

The architectural firm came into contact with Metadecor through the contractor. ‘The design process was complicated: drawing details, finding the right curvature of the panels, experimenting with bending and folding expanded metal’, Wouter recalls. A total of three mock-ups were made to find the right curves for the panels.  ‘When you look at the facade now, you see concave shapes with three different diameters. We had another, smaller element. But the curvature was too angular – did not look great – so we decided against it,’ explains the architect.

Crucial to the flowing appearance was the detail of the connection between the elements. ‘The credits for this detail go to Metadecor. We experimented with folding and setting. The chosen solution, an extruded profile with a rounded strip to which the expanded metal connects, gives the right subtlety.’ For the detail-lovers in our audience: at the entrance to the car park, this detail is visible in cross-section.

Rich colours and shades

The curtain of MD Expanded Metals extrudes sturdily out of the monumental industrial building. The aluminium was anodised, providing an intense experience of the metal. ‘The material has a rich hue in full sunlight; due to the reflections, you can see different colours and patterns in the metal surface at every position of the sun,’ Wouter explains enthusiastically.

Combined with the colourful new residential buildings around it, the Werkplaats Wisselspoor and its metal clad parking garage gives the site an atmosphere that is pleasant for the pioneers of this new residential area.