Glue laminated timber (glulam) is manufactured from strips of timber glued together under high pressure to create a timber beam. This process can be used to create straight or curved beams up to 50m in length. Therefore a roof with a free span in excess of 100m is achievable with glulam. Cross laminated timber (crosslam) is manufatured from sheets of timber glued together under pressure to create a solid timber wall.
A 305mm x 165mm steel 'I' beam has the equivalent strength and performance of a 550mm x 135mm glulam beam but requires approximately 6 times the energy cost to produce. A comparable 400mm x 250mm reinforced concrete beam takes approximately 5 times as much energy to produce and is 600% heavier than an equivalent glulam beam. It is well known that wood has excellent insulation properties whereas steel is a heat conductor. Timberís low thermal mass helps reduce fuel bills by absorbing little space heating energy.
Timber construction is very beneficial for the environment when compared to construction methods using traditional building materials. Firstly, the cycle of tree felling and planting is beneficial to the atmosphere. During the growth stages, a tree absorbs CO≤ and gives off oxygen. Once a tree is mature this process greatly decreases.