Modern wood-based materials from Egger provide a structural basis for exhibition hall roofs

With an effective floor area of 12,500 m2 per hall, the entire complex occupies the equivalent of ten football fields. By far the greatest structural challenge had to be the construction of the unsupported hall roofs with a span of over 75 m. Wood-based products, glass and other materials were used to great effect in this design.
	In situations where solid wood is unable to fulfil requirements in terms of dimensions and load-bearing capacity, composites made from wood and other materials take its place.
This solution not only overcomes the problem of the “limited” size of trees, but it also offers significantly better material properties, since sources of weakness such as knots and other defects in natural wood are largely eliminated in wood-based products. As a consequence, as cross-sections grow slimmer and spans (as in Karlsruhe) grow larger, composites take centre stage. Nevertheless, as highly tensioned structures supporting heavy loads, combined wood and glass designs such as those used at the new exhibition hall in Karlsruhe do require appropriate connecting systems.