Also, passive houses do have proper ventilation:
http://en.wikipedia.org/wiki/Passive_house#Airtightness
> most of the air exchange with exterior is done by controlled ventilation through an heat-exchanger in order to minimize heat loss (or gain, depending on climate)
Without tricks like that, you'll have a hard time getting below 15 kWh/m² per year.
No, you don't. Heating the structure is far more efficient, allows for proper ventilation, and is far more comfortable for the inhabitants.
>Also, passive houses do have proper ventilation:
Yes, but this is not a passive house, that's the point. This is just an airtight box of insulation. They have the least amount of ventilation allowed by code. The air quality in such houses is terrible, and they are very uncomfortable to live in.
>Without tricks like that, you'll have a hard time getting below 15 kWh/m² per year.
You can very easily get to 0 without "tricks" like that. South facing windows + thermal mass.