Engineered wood products or EWPs take a wide range of forms and represent a fast expanding market sector that is enjoying growth in areas traditionally held by solid timber. EWP’s were developed to provide the market with timber construction and manufacturing components that offered guaranteed, uniform strength and performance characteristics. Naturally these come at a price. However, the housebuilder, for one, now recognises that, while the initial material costs may be higher, this is offset against labour charges and the cost of remedial work. They want to be able to build faster and more reliably with a product that meets its purpose.
Of significant advantage to the EWP market is that it is being driven by companies that understand the products’ end application. Historically, the sawmills supplying timber have not always known how their products will be applied. Conversely, the EWP producers are manufacturing items aimed at particular markets and have tailored them to embody the characteristics required. These companies have done research on what the market wants and have the infrastructure to deal with technical enquiries, marketing and customer service.
Glulam
Glulam set the trend for what was to follow within the category and is still a key element used in the structural arena for beams, columns and other heavy-duty applications. The last decade has seen the construction of large glulam factories in central and eastern Europe, dealing mainly with a Continental demand for the product. Consequently, the capacity is such that prices have almost halved in the past five years. It is now cheap enough to be employed almost as a utility material but, due to its historically high cost, it is still widely regarded as an aesthetic product for prestigious jobs in the UK.
Developed to compete with glulam, laminated veneer lumber (LVL) has seen wide acceptance in the UK, partly because it has been cheaper but also for the simple reason that it suits the on-site construction styles that are popular here. LVL is ideal in medium duty structural applications and is frequently the product of choice for both I-beam manufacturers and metal web joist manufacturers; it finds favour in timber framed housing and is used for trimming joists around stairwells in floors. Confirming its place as a mainstream product alongside glulam and solid timber, LVL has recently been awarded its own European standard.
In recent years, timber has been losing market share to I-joists and metal web beams which are fast establishing themselves as the flooring product of choice for housebuilders. I-joists, together with metal web beams, probably have a 40-50% market share and it is predicted that this will rise to 80% or even 90% within three years. This prediction is given extra weight by the fact that competition between the major manufacturers is keeping prices down and service levels up.
Use of technology
Technology is also playing its part. For example, finger-jointing is now accepted as standard in sawmills and production shops as a result of considerable developments in adhesives. Meanwhile, across Europe, machinery is readily available and manufacturing capabilities have expanded. Subsequently, it is relatively easy to get approvals on the products that are being made; the key challenge is to ensure that specifiers really know about these new opportunities.
The future of EWP as a credible and principal means of creating timber floors is signalled by the fact that the NHBC now has specific standards for the use of I-joists and metal web beams as intermediate floors and issues its building warranties accordingly. In addition, the manufacturers have come together to form the Engineered Wood Products Committee of the UK Timber Frame Association. I-joists also have the advantage of now being recognised as Robust Standard Details under Part E of the Building Regulations.
In line with the opportunities for innovation presented by EWP, the companies involved are continually pursuing new concepts.
