COP v3.0:roof-drainage; nzbc-clause-e1-surface-water

5.1 NZBC: Clause E1 — Surface Water 


Safeguard people from injury or illness, and property from damage, caused by surface water

Functional Requirement

Buildings and sitework shall be constructed in a way that protects people and other property from the adverse effect of Surface Water.


Surface water from an event that has 10% probability of occurring annually that is collected or concentrated by buildings, shall be disposed of in a way that avoids damage or nuisance to other property.

Surface water resulting from an event with a 2% probability of occurring annually shall not enter buildings.