Improving the thermal performance of light weight timber construction: a review of approaches and impediments relevant to six test buildings

The BCA's increasing residential thermal performance requirements and their methods of assessment have sparked considerable investigation into the comparative performance of light weight timber framed and high mass concrete floors. This has overshadowed the potential to improve the thermal performance of other parts of conventionally built timber framed buildings. In developing the designs for the six test building in No Bills and Best Five Star Houses project at the University of Tasmania, considerable effort has gone into modifying the detailing and construction of the timber framing to improve their thermal performance, particularly by minimising air infiltration through the floor plate and any wrapping, and preserving the integrity of the insulation layer. This paper presents an overview of international recommendations on high thermal performance timber framed construction, their relevance to regulatory compliance in Australia, and discusses the options pursued in developing the details for a 5 Star and 8.5 Star timber-floored houses to be built and monitored in Hobart and three test cells recently built in Launceston. Conference theme: Building and energy