Natural (passive) ventilation

The supply and removal of air inside a building through natural means. There are two types of natural ventilation occurring in buildings: wind driven ventilation and stack ventilation.


A German-based environmental labelling system for building products. (

Night-time ventilation

Involves cooling the building structure overnight in order to provide a heat sink during the daytime when air temperatures peak. 

Nitrogen oxides (NOx)

Nitrogen Oxide and Nitrogen Dioxide are collectively know as Nitrogen Oxides. Nitrogen Oxides are primarily produced as a result of the combustion process, typically from motor vehicles and power stations. They are one of the precursors for photochemical ozone formation as well as being injurious to human health.

Non-potable water

Non-potable water is water that is not treated to drinking water standards and is not meant for human consumption.

Non-renewable resource

A natural resource that cannot be produced, re-grown, regenerated, or reused on a scale which can sustain its consumption rate.