Innovation must continue to play a lead role if wood is to continue its fight-back against competing materials and if the ‘mindset away from timber’ is to be altered, the chairman of Scottish Forest Industries Cluster (SFIC) leadership group Stefan Kay told the ‘Innovation in Wood Products and Processes’ workshop at the Pentlands Science Park near Edinburgh last week.

Timber is an ‘ancient’ material but, as presentations throughout the day demonstrated, it can be treated in different ways and combined with other materials to result in products that are eminently fit for purpose, he said. ‘We need to come up with products that customers want and can’t get,’ he said.

The workshop was one of two hosted at the end of last month by the SFIC and the National Council for Forest Research and Development (COFORD); the other was staged in Dublin the day before the Edinburgh event. Their purpose was to showcase successful projects and programmes, as well as government funding mechanisms for innovative projects such as Regional Selective Assistance and the SMART, SPUR and TCS schemes.

Timber fight-back

Among those presentations highlighting the timber ‘fight-back’ against alternative and competing materials, British Woodworking Federation (BWF) director Kevin Cubbage produced statistics to back his claim that there had been nothing short of ‘a revolution’ in the timber windows sector since the mid-1990s.

In the past, the timber window industry had invested little in R&D and had generally sold ‘a hole with eight pieces of wood around it’, he said. But through his experience with the BWF‘s Timber Window Accreditation Scheme (TWAS), Mr Cubbage was able to confirm that many British companies were now producing top-quality products and that, just as importantly, ‘there is money to be made from quality timber windows’.

Increasing turnover

From total sales of £180m in 1997, BWF calculated that UK timber window turnover had grown to £255m last year, of which fully-finished and glazed accounted for around £95m. Total sales are expected to hit £290m this year, £350m in 2003 and more than £400m in 2004. And the federation predicts sales of fully-finished and glazed units will top £125m, £180m and £245m in those same three years respectively.

Mr Cubbage emphasised that the battle against competing window materials was ongoing.

Dr Peter Bonfield, director of the Centre for Timber Technology and Construction, BRE, praised the clear value-adding boost provided by the BWF scheme and insisted such innovation was key to future timber industry success. Ongoing product innovation was required to save costs and control quality, while systems innovation was needed to protect/grow markets and to add value.

It was also vital, said Dr Bonfield, for the industry to improve its understanding of clients’ needs and to use materials that were at once ‘consistent’ and ‘tailored’, even if this meant working in harmony with other building materials.

New products

Varied examples of innovation were presented by other workshop speakers, including Professor Robin Mackenzie of Napier University‘s School of the Built Environment. Noting that several surveys had underlined the importance to householders of good sound insulation, he reported on links with the A Proctor group to develop a series of wood and foam-based products that have been shown to deliver excellent sound characteristics. These include a softwood timber batten with an open-cell polymer laminate, as well as chipboard and MDF panels with polymer laminates.

Traditional closed-cell integral foam battens provide as little as 1dB additional sound insulation compared with ordinary timber battens, whereas open-cell foam – whether used in strip form or distributed layer – will provide ‘excellent long-term isolation of impact sound up to 9dB quieter than that obtained using traditional closed-cell battens’, researchers found.

Christopher Mettem, TRADA Technology’s chief research engineer, outlined how even a relatively low-cost project of less than £100,000 had produced new flitch beams incorporating timber and stock steel items as well as fasteners that penetrate both the steel and timber without pre-drilling.

According to Mr Mettem, architects have already begun to recognise the significant potential of these beams owing to their ‘excellent aesthetics, minimisation of shrinkage effects, elimination of unwanted eccentricities and high connection resistance in fire safety engineering’.

Tuula Vartiainen, managing director of Finnish firm Lunawood, spoke of her company’s move into the manufacture of heat-treated wood and wood products some two years ago. Timber felled by subsidiary Lunatimber is subjected to a six-chamber process involving pre-heating, super steam drying, chemical-free heat treatment and cooling/stabilisation.

The process takes between 50-70 hours depending on dimensions and, according to Ms Vartiainen, the result is a 10-15% reduction in equilibrium moisture content, up to a 30% improvement in thermal resistance and reduced water absorption. The final product represented a good alternative to the use of tropical timbers, she suggested.

Lunawood can produce up to 50,000m3 of heat modified timber per year, with main species including Nordic spruce, pine, ash and birch. Leading applications include the furniture industry and floors, panels, doors, windows and fencing for the construction sector.

Jim McBride, chairman of the Irish Timber Frame Manufacturers Association and technical director of Century Homes, shed further light on the innovative TF2000 project with which his company has been involved. Noting that test results from TF2000 had inspired updates of parts 2 to 6 of BS 5268 as well as EC5 and CEN standards where appropriate, Mr McBride spoke of ‘strong indications that three- to four-storey timber frame buildings are becoming more accepted’, but also of slow take-up of the five- and six-storey timber frame option – a fact he attributed in part to lack of awareness of this capability.

Changing standards

Earlier, Jeff Carter of the Scottish Executive‘s Building Standards Division noted that the results from the TF2000 project had enabled changes to be made in the standards for flats up to 18m high so that combustible materials – for example, timber – could be used in separating floors and walls, as well as in external walls in close proximity to the boundary. However, Mr Carter also explained that difficulties in specifying and ensuring repeatability in timber stairs prevented their inclusion, while escape stairs must still be non-combustible.

Turning to timber treatment, Neil Ryan of Arch Timber Systems explained that EU proposals threatened to restrict the use of CCA-treated timber to around 3% of its current applications in the UK. He went on to note the initially muted response to water-based, metal-free alternatives to solvent-based treatments, such as Vacsol Aqua which was launched in the mid-1990s. Since then, there has been a 95% market conversion away from solvents.

Mr Ryan underlined the point that standards and specifications often failed to keep pace with innovation.