2.3 Energy

• Minimise all east and west glazing • Use adjustable shading • Use double glazing and heavy drapes with sealed pelmets to insulate windows • Minimise external wall areas • Use cross-ventilation and passive cooling in summer • Use convective ventilation and heat circulation • Site new buildings for solar access, exposure to cooling breezes and protection from cold winds • Draught seal thoroughly and use entry airlocks • No auxiliary heating or cooling is required in these climates with good design • Use reflective insulation to keep out summer heat • Use bulk insulation to walls, ceilings, and exposed floors.

Climatic Zone 2 is classified as a temperate interior according to the SANS 204. The summer is very hot, with moderate humidity. The winters are cold with low humidity. Summer and winter can exceed the human comfort range.

Some of the best design responses to Climatic Zone 2 are using passive solar principles, high thermal mass solutions, adjustable shading, double glazing, heavy drapes, crossventilations, passive cooling, convective ventilation, and heat circulation. According to these principles, no auxiliary heating or cooling is required if a good design is present.

2.3 Energy

Energy efficiency implies using energy wisely and performing tasks using the least amount of energy possible. Energy efficiency in the built environment can result in energy savings and reduced reliance on coal-powered electricity, positively impacting South Africa's residential sector and natural environment.

Table 4 illustrates the positive environmental implications by saving only one kilowatt-hour of electricity.