In the first decade of the 21st century I was asked to do several surveys of existing houses to see how a retrofitting program of integrated systems could be applied, similar to what I have done with my Mawson house, either by the owner as a DIY project or, if a suitably educated builder could be found (virtually impossible) then a contract could be let if costs could be controlled.

So far (2016) this latter method has not been possible because builders generally do not seem to be interested or are not willing to take on fiddly projects, no matter how integrated and potentially effective.

I have not publicised this retrofitting potential as I am now too old (92) to start a new business and I wish to have time to myself to finish what I have already started – to leave a clean desk for somebody else, especially Maxine.

However, as I have always been saying, designing new efficient houses is all very well but they only represent about 5% of housing stock at any one time – 95% are already built and occupied and if a program could be established on a large scale then this may well be the quickest way to reduce atmospheric pollution.

There is a catch however, the integrated systems I have researched and prototyped at Mawson are based on the Canberra climate – Climatic Zone 7 – see page 2-7 in my book “Making your home sustainable” which are relevant to houses around and below latitude 36º S. In the warmer areas they would need some small modification to suit the micro conditions. Nevertheless, retrofitting would still be appropriate in the face of growing evidence of climate changes over the whole planet.