As part of thinking about building a house, I’ve given consideration to building a super insulated house. In different parts of the world this is called different things, often a passivhaus, named after the German standards.
Once you get reasonable insulation in your house, the main source of heat leakage is through air leakage – cold draughts in your house are a major source of energy loss. Air leakage is controlled through making the house air tight, which in turn relies on an air barrier. In most houses, this barrier is the dry wall / gyprock / gib board (depending on whether you’re American, Australian or kiwi). The trouble with this is that it’s really difficult to keep airtight – think of the opportunities for leakage:
technpol 