Passive design is one of the buzz words in home building at the moment but what does it mean and how do you go about designing or renovating a home that meets passive criteria?
Passive design is a design that takes advantage of the climate to maintain a comfortable temperature range in the home.
Done correctly, it can reduce or eliminate the need for auxiliary heating or cooling, which accounts for about 40 per cent (or much more in some climates) of energy use in the average Australian home.
The importance of passive design cannot be overstated, according to Australian Government website YourHome.
It says: “Paying attention to the principles of good passive design suitable for your climate effectively ‘locks in’ thermal comfort, low heating and cooling bills, and reduces greenhouse gas emissions for the life span of your home.”
TIPS FOR PASSIVE DESIGN
Design for climate: Good passive design ensures that the occupants remain thermally comfortable with minimal auxiliary heating or cooling in the climate where they are built. Each of the eight main climate zones in Australia has its own climatic characteristics. Identifying your own climate zone and gaining an understanding of the principles of thermal comfort helps you make informed design choices.
Orientation: This refers to the way you place your home on its site to take advantage of climatic features such as sun and cooling breezes. Good orientation reduces the need for auxiliary heating and cooling and improves solar access to panels for solar photovoltaics and hot water.
Shading: Shading of your house and outdoor spaces reduces summer temperatures, improves comfort and saves energy. Effective shading — which can include eaves, window awnings, shutters, pergolas and plantings — can block up to 90 percent of heat.
Passive solar heating: This is the least expensive way to heat your home, according to YourHome. Design for passive solar heating keeps out summer sun and lets in winter sun while ensuring that the building envelope keeps that heat inside in winter and allows any built up heat to escape in summer.
Passive cooling: This is the least expensive way to cool your home. To be effective, passive cooling techniques need to cool both the house and the people in it — with elements such as air movement, evaporative cooling and thermal mass.
Sealing your home: Air leakage accounts for 15–25 percent of winter heat loss in buildings and can contribute to significant loss of ‘coolth’ in climates where air conditioners are used. Sealing your home against air leaks is one of the simplest upgrades you can undertake.