Sustainable Tip 6 – what’s good insulation?

Timber floors are cool in summer, warm in winter and more sustainable than cement or tiles

Timber floors are cool in summer, warm in winter and more sustainable than cement or tiles

Good insulation is a material and design which works well in winter and summer and uses least materials.

For a wall:

The outside material is waterproof eg colorbond + next layer is a 50 mm air gap + next layer is Polyair Performa insulation which also acts as a water barrier + rammed earth from the site…

There’s a useful drawing of a wall in Sustainable House p25


For a roof and ceiling:

To conserve materials and achieve high ceilings the ceiling and the roof will be combined eg Ritek which has colorbond and insulation integrated in the one sheet.


For a floor: 

Australian timber with Polyair under it -  never use overseas timber, especially from Malaysia and Indonesia – it is being logged in a massive crime against the rainforests, local people and ecology of those countries – information is in my book, Sustainable Food and in other blogs on my site,….au


Unless the climate freezes there is no need for thick insulation; pink batts are a waste of time and money in most of Australia – a sheet of Polyair works well in winter and summer and has long term efficiency whilst batts decline in efficiency.


For a bathroom floor:

Slatted timber floor with tray below acting as floor waste for whole space will be warm in winter and cool in summer – just hose it down to clean; don’t use tiles as they consume large amounts of energy to make and lay and cause significant building site waste; examples of sustainable bathrooms are on my site: the photo above is from there, too:…


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One Response to “Sustainable Tip 6 – what’s good insulation?”
  1. What a lovely home Mike,

    That is an interesting and practical application of the insulated roofing panel, it certainly saves cost having to install a bulk form or loose insulation between any ceiling cavity. I bet this style of construction also saved a heap a time. Lovely home.

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  • Michael Mobbs

    Michael is a former Environmental Lawyer who is uniquely placed to consult in four main areas:

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