One of the most influential factors to consider when studying ecologically sustainable development, is the advantageous affect that passive cooling and heating can have on the efficiency of a home. This involves the careful selection of materials appropriate to the climate in which the building is situated, the thorough consideration of the orientation of the building to allow adequate ventilation and appropriate solar heat gain and various other factors. By considering all of these aspects the efficiency of the building can increase dramatically, whilst also drastically decreasing the cost of heating and cooling the building.

In the field of ESD, two terms which constantly appear are the U and R values of products, but what do these mean? Whether referring to insulation or glazing each product on the market has a specific either U or R value. These values refer to the thermal performance of specific products and materials and how they assist in maintaining thermal control in a building or structure. These values are an integral part of the BASIX, NatHERS and Section J process in the NCC, which require specific values to be either entered into the glazing calculator for Section J reports or specific glazing types with predetermined U and SHGC values for BASIX and NatHERS along with specific R values for insulation and building materiality.

The NCC sets a minimum acceptable thermal performance for residential dwellings by specifying a minimum 6 star rating for all new projects in Australia with the exception of NSW who are under the BASIX programme.