Sustainable fun with façades

Alongside sustainable building, one of the most pressing concerns among architects is creating affordable housing. One potential solution is to rely on prefabricated components and develop new housing concepts in combination with the use of environmentally compatible products. All three factors come together on a former mining site close to Bochum’s Ruhr-Universität, where ACMS Architekten have succeeded in designing a student residence on the basis of modules an using a hybrid building method: the result is accommodation for 258 people in the “passivhaus” standard. In addition to this, they also designed three L-shaped buildings shielded from the adjoining four-lane road with the skillful incorporation of internal courtyards. The design is based on the “Variowohnen” flexible housing concept, which provides for individual rooms complete with kitchenettes and bathrooms with WC. Thus, up to four people can be accommodated in each unit.

In order to save time and costs, the architects developed the building as a system of largely prefabricated elements – from the outer shell through to the bathrooms. In this way, construction time could be cut by around ten months. The full cladding of the façade was also made ready by the manufacturer: The material chosen was Rieder’s “öko skin”, a type of façade cladding made of fiberglass-reinforced concrete supplied in the form of slatted wall panels, which are produced using very little primary energy from fossil fuels. What’s more, the cladding is also low-maintenance, since fiberglass-reinforced concrete does not need to be polished or painted. Thanks to its thermic values, “öko skin” also guarantees absolute safety and fire-resistance. The individual slats are available in widths from 70 to 302 millimeters and in lengths from 700 to 2,500 millimeters, providing ample scope for individual preferences. Rieder offers not less than four different color schemes, covering grey, beige, red and brown tones oriented towards the varied colors present in nature. Customers can choose between “ferro”, “ferro light” and “matt” for the surface design of the slats, and combining these different surfaces produces a lively interplay of colors on the outer shell of the student residence.

Use of the “anthracite” tone results in a façade that contributes to the building’s dynamic expression and impacts on the surrounding space in various ways. Meanwhile, the interplay of color shades and cloud effects on the surface prevents any kind of uniform appearance and provides for differing perceptions of the building depending on the incidence of light and the angle of viewing. In this way, the arrangement of the “öko skin” offers ample scope for creativity: In Bochum, the vertically positioned slats are staggered for each floor, which lends the façade a sense of depth. The differing grey tones form a contrast here with the light window frames, which likewise form a sculptural element that breaks up the shell of the building.

In order to meet its own requirements for sustainability, Rieder is continually researching and advancing its products and production processes by way of an active contribution to the energy transition. What this means more specifically is limiting wastage through recycling or salvaging of chippings, or avoiding this completely through substitution of the raw materials. Hence, for example, the company uses special tools to reduce waste. What’s more, offcuts from production can be used as a filler material for noise insulation walls or in substructures. In addition, for a long time now all the company’s products have been free of crystalline silicon dioxide and other ingredients harmful to health. Last but not least, the sustainability ideal is also reflected in the longevity of the products which, with their lifespan of more than 50 years, will ensure a lasting yet vibrant image in Bochum and beyond.