Designing with Mother Earth in Mind

Sustainable Homes Series

When you build a home for you and your family to live in what do you look for? Functionable kitchen, good sized bedrooms, storage, Lighting and power outlets and most importantly heating and cooling options. Did you know that an average Australian household uses 40% of its energy to heat or cool the dwelling. Wouldn’t it be awesome if you didn’t have to turn on your heater during winter or your air-conditioning during summer? Imagine saving that money that you pay on your energy bills.

Understanding Humans

An individuals level of comfort depends on a variety of conditions. The environmental condition, our level of activity, type of clothing we wear. Our bodies need a stable temperature of about 37 degrees Celsius. Every individual will have a slightly variable comfort level, for example someone who lives in a warmer climate will be more sensitive to cooler temperatures than a person who lives in a cooler climate. Despite these variations we need to assume a middle ground.


Climatic conditions also cannot be only measured through air temperature as the effect of standing either in the sun or the shade will result in different levels of comfort due to radiant heat. There are also other factors involved such as the humidity in the air and the wind, all this affects our comfort levels.


Most people will feel comfortable in a range between 20 – 27 degrees Celsius during summer and a range of 18 – 24 degrees during winter.

Australian Climate

There are different climatic conditions as mentioned above. In Australia we have about 6 major climatic conditions. In Perth our condition is usually very hot summers (hot and dry) to mild to cold winters. In summer during the day we need to keep the sun and the heat out and, in the evenings, let the cool summer ocean air flow through the residence to cool it down. In winter conditions we need to let the heat and the sun in and keep all the cold air out.


Hence the design principles (Solar Passive Principles) for a comfortable home are very simple.

Principle 1 – Storing heat during Winter

Principle 2 – Excluding heat during Summer


Orientation of the residence is a key factor when designing your home. If the orientation is wrong then the above principles would not work.

click here to read our previous article, which started this sustainable home series.  

We can all save on our energy bills by building a Sustainable Home. To find out how we can design and build an ‘Energy Saving’ sustainable home contact us at [email protected], or alternatively call us on 0401 510 595.