Six Storey Timber Framed Building’s Movement and Moisture Content

The aim of this project was to obtain real data on the temperature, relative humidity, moisture content of timber and vertical displacement of a real, six-storey timber-framed building, during its construction and initial occupation.

Fourteen months of data was obtained over the construction, handover and the early occupation of the building. Twelve months of data were obtained, representing the period the building was enclosed, representing the annual seasonal weather variations.   

The building experienced extreme temperatures variation from minus 0.9 to 47oC, also experienced a very wet period, receiving 87 mm of rain, following six months of very dry conditions. Surprisingly with this variation of weather conditions, the movement recorded within the building was much less than the expected 6.0 mm per storey.

Much of this reduced movement can be attributed to the use of engineered wood floors – Cross-laminated timber and Laminated Veneer Lumber load-bearing studs. The use of these materials reduced movement from crushing and deflection. 

Although beneficial information was found from this research, Western Sydney represents only one climate zone in Australia. It is recommended that further monitoring of timber buildings occur in regions such as Melbourne and Brisbane is undertaken. Furthermore, the data on moisture content is representative of subsurface conditions and not the average of the entire timber element. Explanation or advice is needed to convert subsurface moisture content reading, as recorded in the above research, to the average moisture content of the timber element. This advice is particularly relevant to thick timber elements such as CLT. 


Project Report PRA449-1718