What are the Performance Requirements for timber studs and rafters?

For residential dwellings, NCC Vol 2.0 does impose any requirements for timber studs and rafters. While timber studs and rafters do contribute to thermal bridging to some extent, the NCC considers this impact as negligible.

For non-residential buildings, NCC Vol 1.0 requires assessors to calculate the negative impact of thermal bridging and determine the effective Total R-value for timber-framed walls and ceilings. The calculated effective Total R-value must meet or exceed the required R-value by the NCC.