The Institute of Wood Science (IWSc) might sound like a venerable academic organisation – which of course it is – but that doesn’t mean it’s above mixing a little fun with its daily toil.
Its annual conference, held this year in Liverpool, was a prime example of how the IWSc successfully turns the dissemination of information into an enjoyable – and useful – experience. Its theme this year was innovation in both design and manufacture, with the speakers representing key areas of interest from construction and sawmilling to furniture and e-learning.
The conference teed off with Hugh Mackay, executive chairman of Stewart Milne Timber Systems (SMTS), a company which is riding the crest of the timber frame wave. Mr Mackay’s presentation, ‘Timber frame – a sustainable revolution’ was wholly positive, predicting that timber frame was here to stay – and moving relentlessly south.
Last year’s turnover from the Scottish operation represented around 6,000 timber frame structures per year – or one kit every 30 minutes of the working day. And SMTS’s 2001 turnover of £36m is set to double over a two-year period with the opening of its new automated production facility in Oxford next year.
The company is ‘bucking the trend by setting up manufacturing in England where manufacturing is generally in decline,’ said Mr Mackay. However, he added, as 10 times more houses are built in England than in Scotland, which is a mature market for timber frame, England must be considered a growth market, particularly since the timber frame percentage of new housing here is currently only 6%. ‘It is strongly predicted that the percentage will move to 40% over the next two decades,’ he said. ‘The time is right for investment in purpose-designed factories following the principles of production line techniques adopted many years ago by car plants.’
CAD/CAM was vital to the whole operation, said Mr Mackay, a theme which was taken up by Stephen Wright, director of George Barnsdale & Sons Ltd, a joinery company which, despite its relatively small size (it has 24 employees), has undertaken research into the development of window corner designs and has patented a new system.
Learning from history
However, while extolling the virtues of computer aided design, Mr Wright also maintained that important lessons could be learned from history. ‘If timber remains dry it will have an indefinite life,’ he said, ‘therefore the only problem to long life is keeping it dry.’ Prior to the mid-20th century he said, timber windows were less exposed to the elements because they had brick or stone cills and were installed at the back of the front face of the brickwork. They also had simple throatings to stop water ingress and joints were mortice and tenon, rather than glued and pinned.
George Barnsdale’s research into a corner joint that does not expose the end grain had produced promising results, Mr Wright said, but ‘there needs to be a change in the attitude of people like us designing and manufacturing external joinery’.
Nigel Braden, founder of architectural and construction consultancy Nigel Braden Timber (NBT), has also been involved in research, this time into the use of British hardwoods – specifically sweet chestnut – in construction. Structural testing of sweet chestnut has been carried out and it is to be included in the forthcoming revision of BS 5268 Part 2, he reported.
Modern technology
Modern processing technologies have allowed small dimension timber to be used commercially and NBT and construction manager In Wood Developments Ltd, in partnership with Woodland Enterprises Ltd, have pioneered these advances and demonstrated them in the construction of the new Woodland Enterprise Centre in Flimwell, East Sussex.
The gridshell structure uses primarily locally sourced timber. Chestnut from local coppices provided a high yield of straight grained timber with minimal knots, and stave lengths of between 450-2000mm were finger-jointed and green glued. ‘The roof required approximately 2km of gridshell staves,’ said Mr Braden. ‘All were visually graded and finger-jointed with around 2,500 joints – only two timber failures occurred during installation.’
The application of timber technology to the Woodland Enterprise Centre project had demonstrated the suitability of chestnut for construction, said Mr Braden, adding that he would like to see investment in a hardwood glue laminating plant in the UK.
Archie McConnel, founder of sawmill McConnel Wood Products, reinforced the message that timber can be sold not just as a construction material, but also as a design material. He bemoaned the fact that timber is usually seen as a commodity ‘that is virtually always sold on price’.
‘Timber is not sold as a material to design with,’ he said. ‘We’re not up there with the market leaders because we don’t compete on the cusp of invention. But there’s no reason why timber can’t be “intelligent” the way other materials can be.’
We should broaden our outlook when considering wood as a design material, he said, illustrating his point with examples of avant garde timber construction throughout the world. Many of these examples were built in the 19th and early 20th centuries, leading him to advocate ‘using the past to design the future’.
Thinking outside the box
‘You don’t always have to think that far out the box to come up with something innovative’: that was the message from Dr Peter Beele, head of research and testing at the Furniture Industry Research Association (FIRA). He is also chairman of the 2020 Vision working group which has been responsible for preparing a UK furniture industry research and innovation strategy for presentation to government.
He reminded delegates that, while emphasis is currently on construction, the furniture industry is by far the main user of timber – 56% of the e150bn EU wood production market and with UK sales exceeding £7bn per year. And innovation is of paramount importance if there is to be competitive growth. ‘Innovation to the benefit of the furniture industry equals growth and development of the timber industry.
‘To the timber industry’s credit, innovation is something with which it is becoming increasingly comfortable,’ he said. ‘Companies… have taken major research and innovation steps to protect and develop their furniture based markets. These cover a diverse range of work including powdercoating of wood and MDF, modifying MDF to improve the uptake of powders, utilisation of small woodlands, artificially darkening timber using ultra violet light [negating the use of volatile organic compounds to speed the drying process of stains and tinted finishes] and composting of wood dust.’
While Dr Beele was representing a huge market sector, Martyn Spence, director of HLD Ltd spoke on behalf of what he called ‘almost a cottage industry’.
HLD spends 60-70% of its time designing and building bridges and is one of only a few bridge building companies in the UK.
Like other speakers before him, Mr Spence harked back to the past: ‘Timber was the first bridge building material and its use pre-dates any other material by many thousands of years.’
The past 10 years had seen a welcome renaissance in timber bridge building (thanks largely to a rash of new golf courses and the booming garden market), he said and, whereas naturally durable hardwoods would have been the automatic material of choice, ‘preservative treated softwood is now well established as an alternative material, combining good performance with lower material cost and offering a greater degree of sustainability’.
Fit for purpose
The key to HLD’s success, he said, was that its bridges were fit for purpose. ‘We design timber bridges, not bridges that happen to be subsequently made from timber. The bridge is designed with the material in mind and with its properties clearly defined, understood and utilised in the structure.’
Success in the future when access to CCA treatment may become restricted, he said, would depend on the ability to design structures differently, devising systems and details which minimise the risk of decay. Such designs were already employed in Europe, he said, and included protecting vulnerable timbers from wetting by the use of coatings and waterproofing measures and modifying joint details to eliminate water traps and improve air circulation.
Many of the speakers held up the automotive industry as a shining example of innovative manufacturing processes, so it was appropriate that Jaguar Cars Ltd, which was one of the conference sponsors, should also field a speaker.
Terry Williams is principal engineer of Jaguar’s veneer manufacturing centre, the largest purchaser and user of burr walnut in the country and which employs 415 people – making it ‘one of the biggest players in the UK’.
He explained how Jaguar had used Ital Presse technology to form, with tooling, complex shapes in wood. ‘The developments in this process have moved light years from our first simple offerings,’ he said.
Mr Williams predicted that consumers would want the same sort of changes in their cars as they currently enjoy in their homes. ‘So do not be surprised to see laminate floor parts in cars of the future,’ he said.
Other possibilities over the next five years include the use of ‘blond’ woods such as ash and beech, dark, linear veneers, laminate seat backs and even bamboo. ‘The future is here now,’ concluded Mr Williams. ‘We have to develop or die’.
