After monitoring the movement and moisture content of a timber-framed, mid-rise building, researches have collected data to help build confidence and acceptance of wood amongst the construction industry.
During the past 18 months a research team led by Andrew Dunn, CEO of the Timber Development Association of NSW, collected data relating to the performance and extent of movement observed in a recently completed building in Sydney.
Movement in buildings can be attributed to closure of timber joints, compression and shrinkage of vertical and horizontal elements, timber deformation, and the deflection of the support structure, amongst other things.
Mr Dunn said the team was prompted to undertake the research by a lack of existing data relating to the performance of mid-rise, timber-framed buildings in Australia.
“Various assumptions have been made around the long-term performance of timber-framed, mid-rise buildings in other parts of the world, but ultimately, they were found not to apply to the Australian climate,” Dunn said.
With timber use in mid-rise construction still a relatively recent development in Australia, researchers recognised the importance of being able to provide proven data. The hope for this data was that it would position timber as a viable, safe, robust and long-lasting option for mid-rise construction. The ultimate goal of the research project was increased confidence, acceptance and use of timber systems in the building trade.
“The best way to understand the performance of a building is to measure a real-life example,” said Dunn.
In mid-2019 the team identified a six-storey, timber-framed building in Sydney that had recently been completed and was yet to be occupied. Having already made a number of theoretical assumptions — published in WoodSolutions guide no. 50, mid-rise timber building structural engineering — the team was keen to test these in practice.
“We were pleased to note that in measuring the likes of vertical displacement, temperature, relative humidity and moisture content, our initial assumptions were validated through the course of the project,” said Dunn.
Analysis confirmed any compression, shrinkage, deformation or moisture levels associated with the timber frame would be minimal and of no concern to the building’s integrity. In fact, the issues were found to be no more concerning than similar issues associated with alternative construction materials.
Despite the strength of the results, monitoring continues, with data to be collected up until the end of this year. At that stage, the research team will have statistics covering a full year of occupation, and the varying climates of all four seasons.
This FWPA-supported project, titled Monitoring Mid-Rise Timber-Framed Building for Movement and Moisture Content, is an example of an investment in real-world construction field research, for the benefit of timber systems.
