Photos of this house (extension designed by Christopher Megowan) can be found here, but it wasn’t until I saw the above diagram that I actually realised what they had done.  A bit like looking at those ‘spot the difference’ pictures and not noticing anything….  You might also like the aqueduct guttering – again, not immediately obvious.  Here is an animation of the roof being moved from one side to the other.

This house is in Melbourne – apparently the weather is fickle :-)