Living in a Material World
Government influence
The Government, through the Ministry of Agriculture and Forestry, has recently provided funding for the promotion of timber in buildings. University education in structural timber engineering is already making an impact.
As the owner of many major capital developments, the Government is in a unique position to influence material selection. It would be politically difficult for government to require that more timber be used in new buildings, but it would be easy to specify that a timber alternative be considered for all new government funded buildings. For a very small increase in design fees, architects and structural engineers would be enthusiastic about creating a timber design for comparison with more conventional materials in significant projects. There are several benefits to this approach:
- The comparative cost of timber and other materials would become apparent over a wide range of projects.
- The cost of the extra design time would be small compared with potential savings from more competitive design and construction practices.
- The results of such comparisons would establish the strengths and weaknesses of timber solutions, and areas for necessary research.
- Public money would not be wasted constructing timber buildings unless they have been shown to be cost effective.
- Designers would become familiar with working in timber, even if some of their timber designs are not built in the first instance.
Some building owners already engage designers to compare alternative structures in steel and concrete, for example, in multi-storey building developments, so this approach is already accepted in the building industry.
Such a government policy need not apply immediately to all buildings, but might initially apply to educational buildings,for example, then progressively to commercial, industrial and other buildings in the government portfolio. Industry organisations Opportunities for the use of timber in buildings are limited by the lack of a single, focussed organisation encouraging research into, and promotion and development of timber as a building material.
All sectors of the construction industry obtain confidence from research into building performance issues such as wind, fire and earthquake resistance, noise control, thermal behaviour and durability. If the construction industry is to embrace more use of timber, more research will be needed, as is the publication of design aids to provide confidence in timber's structural design potential, in areas such as durability, acoustics, sustainability, and thermal performance.
There is no New Zealand-wide organisation promoting the use of timber in new buildings, funding research into timber solutions, or providing the technical base which designers need. Scion (formerly Forest Research) plays a useful role in researching the quality of timber and wood products, supporting building code developments, and testing new assemblies and products. University researchers undertake similar activities. The Building Research Association of New Zealand is involved in assessing the strength and safety of houses and other timber buildings, but cannot promote timber as it maintains a material-neutral position. The Timber Industry Federation publishes the Timber Design Guide, a useful reference document. The New Zealand Timber Design Society is a group of enthusiasts who make a large impact for their small numbers and publish the New Zealand Timber Design Journal.
The combined efforts of all these groups, however, do not compare well with those of the organisations representing competing materials. Major structural materials such as steel and concrete have organisations that support research, technical advice and promotional activities. The effectiveness of new organisations including the Wood Processors Association and the Wood Council (WoodCo) will be followed with interest.
Summary
Three steps would encourage a significant increase in timber use in new buildings:
- Companies in the timber industry could ensure that timber is used for the design of all new buildings over which they have control.
- The Government could require that an alternative design in timber be executed for any new building it commissions.
- The timber industry could establish a new organisation to support research, technical advice and promotion of the use of structural timber.
The implementation of one or more of these initiatives could significantly increase the use of timber and other wood products in New Zealand buildings.
Professor Andy Buchanan FIPENZ is Chair of Timber Design at the Department of Civil Engineering, University of Canterbury.
