Wooden venues

A look at several sports structures in Germany made of timber

Sports events with growing numbers of spectators have become mass events disseminated by all kinds of media, triggering a boom in the construction of new sports structures worldwide. These tasks are not, however, solely the domain of steel and concrete. They can also be implemented with a renewable material like wood. This is proven by some architecturally sophisticated examples from Germany.

"Expo roof" in Hannover

Wood has always had a very close relationship to sports – and not only in case of sports equipment and hall furniture. Wood is an elastic material that is pleasant to touch, it possesses high strength and yet it is light. Laminated structural engineering first appeared at the end of the 19th century in Europe with the development of new timber construction materials. It not only coped with the requirement of large spans in sports structures but also permitted the assembly of numerous public and private timber constructions of all kinds.

Over 30 years ago timber construction was able to prove its performance to millions of spectators during the Olympic Games 1972 in Munich. For these Olympics, a number of important sports structures were realised in timber. For example the velodrome had a timber construction supporting both the stands and the roof. The stand cover and the cycling track itself were also made from wood. Yet it is not a temporary structure and is still being used for competitions and leisure events today.

Timber construction in Germany has also produced milestones in connection with other events not directly relating to sports. An example is the "Multihalle", an unusual building, which was created in 1975 for a horticultural show in Mannheim. The planners broke new ground with a simple lattice construction of wooden laths and a skin of plastic film which covers a multi-purpose hall, a café and a restaurant in the form of a 20m-high hilly landscape without any columns. After 25 years of intensive use, this "master piece of civil engineering" was declared a cultural monument in 2000 and continues to be very popular with numerous visitors.

These two historic examples are not only an endorsement of wood’s technical or aesthetic qualities but also its long life. Germany possesses impressive examples of wooden houses aged 500 years and more. Current research results also certify that contemporary timber structures possess at least the same service life as other materials. And companies dealing with timber construction possess high innovation potential and often act as a motor for development. Architects and civil engineers keen on experimenting create extraordinary buildings winning recognition from specialists, increasing the popularity of the material in the general public.

Sporthalle Berlin

A special opportunity to spread the innovative spirit of German civil engineers dealing with timber construction came at the world fair Expo 2000 in Hannover. In the centre of the fair area the world's largest wooden roof was built and soon became the unofficial landmark of the Expo for visitors from all over the world. It covers an area of 16,000 sq m with several pavilions and consists of 10 single wooden umbrellas connected with each other at a height of 26m. As planned in advance, after the Expo closed, the roof now serves as the centrepiece of Germany’s largest exhibition area.

Today, more than ever, the enormous financial expenditure for the organisation of temporary events like the Olympic Games necessitates implementing concepts for the long-term use of buildings – embedding them into city planning. Investments concerning sports structures and peripheral facilities offer a good chance to create and to extend a modern infrastructure, which in the long run is a benefit to everyone on a national level.

Besides technical progress, ecological questions have helped timber construction to experience a boom in the past 30 years. This is because wood is the only regenerating material. In Germany, wood comes from forests with sustained yield economy. This means that in one period no more wood is cut than will grow again. In this way, future generations will permanently have this raw material available. Harvesting, processing and transport are achieved with a relatively small amount of energy. As a light material, timber is offered in a large variety of types and features as well as in most different material shapes on international markets.

Wood’s influence on architecture can been seen at an unusual building that was created in Berlin in 2002. Under a wave-shaped roof a large sports field and several training fields were accommodated. Spanning a distance of 7.5m, prominent frames of laminated timber cross several buildings. At one side, the roof is open towards the sky. Here javelin throwers have a weatherproof delivery point.

The multi-functional SAP Arena in Mannheim

Also in Berlin is a sports hall where the architect managed to accommodate two halls by positioning them one above the other. The upper floor houses a room the size of a handball field, which is covered by an extraordinary barrel-shell roof of diamond-shaped timber bars. Instead of the ventilation systems normally existing in gymnasiums, fine tendons of steel and suspension devices for the sports equipment convey a free and open atmosphere.

With regard to structural design, the performance of timber is comparable with steel and concrete. Particularly with spans, timber also offers the benefit of a considerably lower self-weight as compared with concrete girders, for example. This fact facilitates a prefabrication of complex compound units under the protected conditions of a timber construction operation and reduces the expenditure for transport and installation. Another advantage is the fact that bearing structures of timber can be loaded immediately after installation without any drying time.

For the most part, roofing over large areas in sports and leisure structures calls for column-free bearing structures for large spans. Arched bearing structures and truss girders meet these requirements without any problems. Often the wooden bearing structures of sports structures remain visible. The natural charm of the frequently untreated timber surfaces gives a friendly atmosphere upon rooms.

A current example of the bridging of a very big hall is the SAP Arena in Mannheim. This is a multi-functional hall that even includes an expanse of ice for the city’s successful ice-hockey team. Truss girders of laminated grey timber form an elliptically rounded roof and in the hall interior accommodate considerable additional loads for air-conditioning and media systems. In the hall’s centre, the girders are 8.5m-high, and with their free span of 88m, they are the largest of their kind in Germany. The clients initially wanted to have a steel construction. Once informed about the prices, however, they were easily convinced of the fact that curved structures can be realised in timber much more easily and thus more cost-effectively. This benefit of a competitive price has won some large projects for timber construction in recent years.

Another remarkable fact is that timber, unlike other building materials, is not subject to corrosion. This circumstance makes it ideal for use in swimming stadiums and ice sports halls – buildings with a relatively high atmospheric humidity inside. A good example is the sports pool in Minden, the roof construction of which consists of a timber frame with a 37m span. The large structural members, each weighing five tonnes, were installed in less than 30 days.

The high standard of timber constructions in Germany is based upon the quality of highly developed construction materials. Architecturally appealing and technically perfect buildings require dry, non-deformable materials possessing an excellent surface finish and a high durability - available in all conceivable dimensions and material qualities. And wood fits the bill perfectly.