Description

BRANZ reviewed the current building regulations for managing fire spread from roofs to adjacent taller buildings and compared them with the regulations in five other countries. New Zealand has the most stringent requirements for fire protection in this specific context, but general wall and roof requirements in other countries can provide a similar or greater level of protection. New Zealand regulations require fire protection across 9 m height in adjacent external walls or 5 m width in lower roofs. BRANZ investigated the origin of this requirement and found this approach most likely came from international code NFPA 80A Recommended practice for protection of buildings from fire exposure.

The increasing demand for housing is driving higher-density development in urban areas in New Zealand. This increases the risk of fire spreading between buildings, including from roofs that are lower than the walls of nearby adjacent buildings.

Scope

In this research:

• Comparing New Zealand and overseas regulations
  • Performance-based requirements
  • Specific prescriptive requirements for fire spread from lower roofs
  • General roof and external wall requirements
• Origin of New Zealand prescriptive requirements
• Recommendations