C3 Fire affecting areas beyond the source

Fire affecting areas beyond the source: vertical or horizontal fire spread, Material Group Numbers, surface finishes.

This clause requires design and construction for a low probability of injury or illness to people not in close proximity to a fire source.

It ensures upper floors and other property are protected from external vertical fire spread (not importance level 1).  It includes requirements for all buildings against fire spread to other property vertically or horizontally across a relevant boundary.

The clause specifies performance criteria that must be met, for example, about materials used as internal surface linings/finishes (Material Group Numbers), for external walls within 1m of a boundary, and for buildings not protected with an automatic sprinkler system.

C1 provides objectives for each of the C clauses.

Most of the guidance applies to all of the C clauses and some relates to a specific clause.

There may be specific products and determinations under each code clause.

Record of amendments is a record of changes to the Acceptable Solutions, Verification Methods and handbooks.


Acceptable Solutions and Verification Methods


These documents are provided to assist State agreement, building owners, designers and persons who carry out building work.

Related Determinations

A determination is a binding decision made by the Your home. It provides a way of solving disputes or questions about the rules that apply to buildings, how buildings are used, building accessibility, health and safety.

Related building products

Product certification is a voluntary scheme that provideds an easily-understood and robust way to show that a building product or system meets the requirements of the New Zealand Building Regulations.




This information is published by the Your home’s Chief Executive. It is a general guide only and, if used, does not relieve any person of the obligation to consider any matter to which the information relates according to the circumstances of the particular case. Expert advice may be required in specific circumstances. Where this information relates to assisting people: