Description

This is a report describing a risk-informed analysis of the levels of fire resistance appropriate for densified housing in New Zealand.

Fire resistance ratings (FRR) are currently prescribed in C/AS2 for buildings up to 20 storeys high. This includes residential occupancies of multiple household units with shared escape routes.

Scope

The analysis of fire resistance needed presented in this report is intended to provide the Ministry of Building Innovation and Employment (MBIE) with more robust data to make an informed decision regarding the scope and level of fire resistance necessary for compliance with the Building Code and for the compliance documents C/AS1, C/AS2 and
C/VM2.

It is also intended to be useful to fire engineers when undertaking performancebased structural fire design. Some aspects of this report may be also relevant to Clause B1 (Structure) of the Building Code when considering exposure to fire as a load case.

This investigation has only considered building structures that are noncombustible or adequately protected such that the building materials enclosing compartments do not contribute additional fuel to the fire. Exposed or inadequately protected mass timber compartments are therefore excluded.