Principle 2: Catch and store energy
When I went to check out the second-hand water tank that I was looking to buy I came across a large window on the site. It was made from Western Red Cedar, a soft timber that is naturally resistant to decay. The panes and doors were in good condion, but the supporting frame was not, as it had been stacked straight on the ground and left out in the weather for years. The glass was single glazed (probably laminated) and it had a double sliding doors. I thought that it might be useful as the northern window and asked a friend what I should offer for it. I offered A$300 and paid A$400. I thought it was a good deal - and it came with two sliding fly screen doors (Principle 3). It would cost about A$5000 or more new.
Second-hand windows I purchased for A$400
It took four guys to lift the thing and load it onto the tri-axle trailer. When we got it to the site we decided to separate the panels and make up a new frame. It was als…