Passive design is design that does not require mechanical heating or cooling. Homes that are passively designed take advantage of natural energy flows to maintain thermal comfort.

Incorporating the principles of passive design in your home:

• Significantly improves comfort
• Reduces or eliminates heating and cooling bills
• Reduces greenhouse gas emissions from heating, cooling, mechanical ventilation and lighting. 

Building envelope is a term used to describe the roof, walls, windows, floors and internal walls of a home. The envelope controls heat gain in summer and heat loss in winter. Its performance in modifying or filtering climatic extremes is greatly improved by passive design. Well designed envelopes maximise cooling air movement and exclude sun in summer. 

In winter, they trap and store heat from the sun and minimise heat loss to the external environment. The fundamental principles of passive design, explained above are relatively simple but they must be applied to a vast range of climates, house types and construction systems in Australia.

On average, 39% of energy consumed in Australian homes is space heating & cooling. Using passive solar design dramatically reduces this figure. 

WHAT IS PASSIVE SOLAR HEATING?

Passive solar heating is the least expensive way to heat your home. It is also:

• Free when designed into a new home or addition.
• Appropriate for all climates where winter heating is required (generally latitudes south of 27.50S).
• Achievable when building or renovating on any site with solar access - often with little effort.
• Achievable when buying a project home, with correct orientation and slight floor plan changes.
• Achievable when choosing an existing house, villa or unit. Look for good orientation and shading.
• Achievable using all types of Australian construction systems.

Put simply, design for passive solar heating is about 
keeping summer sun out and letting winter sun in.

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