It's not all about numbers, really there's more.
I have probably quoted Kiwi architect Elrond Burrell more than any other living architect; his blog on Passivhaus (or PassiveHouse) is invaluable.(See related links at bottom for my posts that reference him). I even named a new green building standard after him. One of the things I really looked forward to at the 22nd International Passivhaus Conference in Munich was actually meeting him in person and hearing him speak as one of the keynotes.
Elrond, like myself, spends a lot of time trying to explain the benefits of Passivhaus that go beyond just saving energy and reducing carbon emissions, although that should be enough on its own. But it's not, particularly in an era of cheap fuel prices. So Elrond explained why he loves PassiveHouse so much:
Architectural design is typically carried out with little or no environmental consideration during the design process. Once the design has reached a certain stage, it is assessed so that "environmental features" can be added.
Elrond suggests that PassiveHouse is different, and that design is baked into it from day one, that "design is central to Passive House." I am not sure that I agree here; I have seen some really ugly PassiveHouse buildings and houses. But Elrond's basic point is valid; PassiveHouse design avoids what Philadelphia builder Nic Darling called "Polishing the turd", building the same thing that they always did but just tacking stuff on.
So, they polish the turd. Rather than redesign the house that has been successful for them in the past, they add solar panels, geothermal systems, high end interior fixtures, extra insulation and other green features. The house gets greener. It gets certified, but it also increases significantly in cost. Since the features are add-ons and extras, the price rises as each one is tacked on.
PassiveHouse avoids that by keeping it simple.
Building standards are often confusing and aspirational, failing to deliver what they claim. There is integrity in the clarity and simplicity of the Passive House Standard performance requirements.
Integrity perhaps; I have never heard anyone describe achieving it as simple. Just look at that spreadsheet! But the concept has always been clear: you can burn so much energy per unit area, and have just so many air changes. Everything else is commentary.
Architecture is often described as a combination of art and science. Art is subjective; however, buildings have no choice but to obey the laws of science.
Alas, this is why many architects avoid doing PassiveHouse; it's hard to turn them into art. You need real talent to get rid of jogs and bump outs and big windows, to make it, as Bronwyn Barry calls it, Boxy But Beautiful. But these days more and more architects are figuring it out and doing beautiful buildings that just happen to be PassiveHouse certified. And finally, Elrond talks about:
The construction industry often feels fragmented and adversarial. Passive House is different... There is a very strong global Passive House community.
At the conference in Munich it certainly felt like there was a community. Alas, in North America the community is still a bit fragmented and adversarial.
I found Elrond's talk to be inspiring, accessible and refreshing, but it appeared that the other energy nerds in the room were not as seduced by its charms as I was; they would rather look at data. This is a shame; there are many ways to save energy or go Net Zero that don't deliver these benefits. Integrity, comfort, community and design, all those subjective attributes of PassiveHouse, are ultimately what people really care about. They should listen and learn.