We have to rebuild our cities to use less energy and house more people, and Passivhaus design is a useful tool for both problems.
Starting on Friday, the leaders of the Passive House movement around the world are meeting in Munich for the International Passive House conference. Passive House, or Passivhaus, is probably the toughest energy efficiency standard anywhere; houses that meet the standard have super insulation, minimal thermal bridging, high quality windows and controlled ventilation. They are comfortable to live in and cost almost nothing to heat and cool.
I am a huge fan of Passive House, and am attending the conference in Munich, but I am increasingly convinced that it simply isn't enough anymore. Because what is really driving our energy consumption these days is transportation, where we are going backwards. It's sprawl, and it's the form of our housing. It is how we get between our houses and where we work or shop. Passivhaus can be applied to any kind of building, but expensive single family designs out in the country are not going to move the needle on our problems.When I spoke at last year's Passivhaus conference in Austria, I suggested that as well as exporting the idea of Passivhaus, we had to export the idea of Vienna- where almost everyone lives in lovely apartments in mid-rise buildings, where there is wonderful transit and bicycle infrastructure just about everywhere.
Because when you build multifamily housing, it doesn't cost nearly as much to make it Passivhaus efficient; instead of having four walls, a roof and a floor to insulate to such high levels, most units have one, maybe two exposures.
When you live in multifamily housing, you often don't need to own a big SUV to go to Walmart for your weekly shopping; there is enough density to support a decent number of stores within walking or biking distance. Since transportation now consumes more energy than housing, that's important. In a city of a reasonable density, those electric bikes I have been talking about can really do the job, carry what you need, and take up a lot less space.
In multifamily housing it is much easier to age in place, since the units often have to be designed to universal standards, are usually on one level with elevator access, and there is a larger support network nearby. You tend to be closer to doctors and other services that you need.
Finally, when you build multifamily housing, it uses far fewer resources. As Paul Simon put it so well, one man's ceiling is another man's floor. The homes are often smaller because the community provides many of the the functions that suburban houses have built in, there are theatres instead of media rooms. It just uses so much less material, so much less embodied energy. And that is not even talking about the externalities, the roads, the schools and fire trucks that are needed to cover so much more area.
I often cringe at what Elon Musk calls the Future We Want, with big suburban houses full of solar roofs and Powerwalls and two Teslas in every garage; it doesn't scale. It won't even serve the one percent, let alone everyone else.
I do not believe that one can build Alan Berger and Joel Kotkin's Infinite Suburbia, “a different kind of suburban development that is smart, efficient and sustainable.” It is a fantasy.
We also have a massive housing crisis in successful cities like New York or Seattle in the States or Toronto and Vancouver in Canada where young people cannot afford to live, because new mid-rise housing is almost impossible to build thanks to NIMBY zoning. We have to build a lot more mid-rise multifamily to accommodate them.
I have become convinced that the only way we should be building these days is mid-rise out of wood, in communities connected by foot, bike and transit. I am not sure we can seriously reduce our carbon footprint any other way.
I will be covering the conference in Munich and moderating a panel discussion on deep urban retrofits, on fixing our cities. I might well write about a few lovely houses. But our problems today are much bigger than that, and I will be concentrating on that mid-rise housing that I call the Goldilocks Density, preferably in Passive.