A parking garage made almost entirely of wood

Premiere in the Seeland: the first wooden parking garage is being built in Studen near Biel.

There have already been a number of projects for a wooden parking garage. But no one dared to implement until recently. In Studen near Biel, however, the first wooden parking garage in Switzerland is now being built.

The wooden parking garage in Studen, which is not quite finished yet, may not be an architectural marvel, but it is a constructive one, and it hides its wonders too. What the visitor sees does not appear to be very spectacular: three parking levels measuring 51 by 165 meters, supported by wooden pillars and girders, stacked one on top of the other. The construction radiates sober practicality in every detail. But one that has it all.

Because this design and cost minimalism is demanding in planning and construction. "It's a brutally simple construction," says Stephan Zaugg, who designed and built the pioneering building with his timber construction company, Zaugg AG Rohrbach. And brutally simple in this case means optimized for maximum performance with minimum effort.

The ceilings, for example, are made of ten-meter-long, very thick cross-laminated timber panels that are mounted directly on the main beams that follow every five meters. The additional beam layer that is usually used for such load-bearing distances is missing. That reduces with the number of connections the assembly expenditure and thus the costs markedly.

Sophisticated logistics

The assembly itself is also one of these invisible wonders. Indeed, the biggest challenge in building the parking garage was logistics, Zaugg says. In order to build it efficiently, the production of the components and their transport to the construction site had to follow a precise timetable.

One "flaw" in the first Swiss wooden parking lot is that both the components and a large part of the wood come from Austria. "Unfortunately, we don't have a semi-manufacturing industry in Switzerland with the necessary capacity," says Zaugg. A total of 1100 m3 of glulam, 3400 m3 of cross laminated timber panels and 30 m3 of beech wood were used for the parking garage.

However, with a pioneer building, it also needed a builder to take the risk of a first work. In this case, it was Cotra Autotransport Ltd. The company had the hitherto unsolvable problem of wanting to build a parking garage for 2,000 vehicles on an area with groundwater.

Because the groundwater allowed only a low soil load, the usual construction method with concrete was out of the question. The parking garage had to be light – for example, made of wood. A wooden construction also had the advantage of being cheaper and even faster to build if the construction method was optimized.

No sprinkler system

But what about fire safety? While the fire hazard still seems somewhat controllable in residential construction, wood and cars, and therefore gasoline, are a poor match at first glance.

However, fire protection was not a problem at all, says Zaugg. Here, the builder and designers have benefited from the 2015 relaxation of Swiss fire regulations, which until then had prevented timber construction. A few planning tricks were also helpful. The dimensions and design of the parking garage were planned precisely so that it did not have to meet any increased fire protection requirements for this purpose. Therefore, the wooden building does not need fire walls, sprinkler system and fire locks.

Unique in the world

On the other hand, some extra effort was made to make the construction weatherproof. In order not to expose any structural parts to rain and snow, the facade supports of the building were made of hot-dip galvanized steel. Also the access ramps. The access stairs are made of steel. The roof area, which is also used for parking, is protected by a layer of asphalt. The building is not quite finished, but it is already in use. Finally, the building is scheduled for acceptance at the end of March 2018. Switzerland will officially have its first wooden parking garage.