As the Olympics loom and London steps up a gear, TRADA engineer Hugh Mansfield-Williams explains why timber and sports structures are the ideal match

Large sports arenas are culturally significant structures. Their sponsors have aspirations not only to sporting success, but also to promote a particular set of values.

The greater the exposure of the structure to the public gaze, the greater the emphasis on the message that it is intended to convey.

Nowadays the message is always mixed: the building should be iconic, without being triumphialist; it should be of high quality, but a wise use of public money; it should be ideal for its purpose, but suitable for multiple uses.

The funding body and planning authorities will also have specific concerns that will affect the overall outcome. They may require that its design meets certain environmental criteria or that it is useful to the local community.

If the arena is built for a specific event, then it must have a clear continued purpose, which is part of the legacy of the event.

As an example of the demands that a sports arena has to satisfy, the Olympic Movement has a stated aim to “further encourage and facilitate strong environmental actions, technology and product development in a city, country and beyond, through the educational value of good example”.

Architects must demonstrate that their proposals are the best way of meeting such criteria. Timber has a number of particular advantages for those seeking to satisfy conflicting constraints for large sports arenas. To begin with, timber has a unique aesthetic appeal.

People feel that it is a warm material, imparting an intimacy that partly offsets the vast size of the enclosed space in some sports arenas. The relationship between the forest and timber structures is appreciated by communities in well-forested areas, who often specify timber for their public and private buildings.

Timber has specific structural advantages. The most common timber product for wide span structures is glued laminated timber, or glulam, which is manufactured off-site. A wide range of species can be used including locally sourced timber, which reduces transport distances.

Glulam can be straight with a constant cross-section, or curved, or with a varying cross-section. Transport restrictions usually limit the length to around 20m, but individual lengths can be fastened with steel connectors to large girders or frameworks.

This article is an extract from IRISH CONSTRUCTION INDUSTRY MAGAZINE - CLICK HERE TO SUBSCRIBE TODAY!