As far as I can tell, it's a standard which just means that the building needs very little energy for heating or cooling. It mostly comes down to making the bui

As far as I can tell, it's a standard which just means that the building needs very little energy for heating or cooling. It mostly comes down to making the building very insulated (as far as I can tell--not saying that's the complete story, but that's a big factor). https://en.wikipedia.org/wiki/Passive_house https://en.wikipedia.org/wiki/Passive_house