ER53 Measuring the extent of thermal bridging in external timber-framed walls in New Zealand (2020)

This report shares the results and findings of a project to investigate the extent of thermal bridging in external timber-framed walls of new builds. The project took a case study approach to investigate the percentage of framing in 47 newly constructed dwellings from Auckland, Christchurch, Wellington and Hamilton.

The results show that the average percentage of timber framing compared to the area of the wall is above 34%. This is much higher than the 14-18% framing content generally assumed by both regulators and the industry. The results strongly indicate that the content of timber framing in external walls in residential new builds is at such high levels that the increased thermal bridging compromises the performance of walls and may mean that designed R-values are not being achieved.

See the BRANZ Research Now for a short and accessible summary of this report