It depends where you live in Perth Hills or beach. You need to catch the doctor from 11 am on in Summer, so high clerestory windows on SW that can be shaded for the afternoon heat. a northern heat stink is ideal for winter to warmth into the house. You can get from the BOM a Breeze map, then unlucky also need the CSIRO book on building a passive house. There are also charts of the sun obits in all season, solar installers work with them. To build a passive house one has to work with the known science to make the best use of a passive house. Then work with the building materials. I built a passive house in Brisbane, after living in Perth for 20 years. I have used sandwiched steel, and all the passive tricks. No ac, and totally liveable in high 30s and 80% humidity.
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Study at the top of the stairs
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