Should we be building like Grandma's house or like Passive House?
For many years I have been promoting simple, non-electric ways of keeping cool without air conditioning. Most of the techniques were based on how our grandparents kept cool by living in houses that were designed to be as comfortable as possible without air conditioning, because they had no choice; air conditioning did not exist. So they designed their houses with all the features that I have been promoting for years, neatly summarized in a post on the Solar City blog, including large double-hung windows, high ceilings, porches, thick masonry walls and tuning windows for maximum air flow.
These are all wonderful ideas. And they work, if you have a nice single family house with land and breezes and trees. But only a small proportion of the population can afford that anymore, and there are other issues with single family housing. We need enough density to promote cycling, support transit and local retail. You can’t do that easily on a suburban single family model.
© 20 Niagara Street Toronto
It's not like I haven't tried. I applied these ideas to multiple family housing in a project in Toronto almost twenty years ago, a little condo building with high ceilings and no corridors so that everyone had windows front and back for cross ventilation. It has not been copied as a model for good reasons: it is expensive and it doesn’t scale.
For many years I have also preached that in winter, one should turn down the thermostat and listen to Jimmy Carter, who told us to put on a sweater. Essentially, I have advised people to suffer a bit. Get used to being colder in winter and hotter in summer. Discomfort was in fact a big part of the green movement: no flying, no meat, no air conditioning, freeze in winter, have staycations. Wear a hairshirt and mittens. No wonder Jimmy Carter lost and the green movement has been going nowhere. Because people want to be comfortable. People don’t want to freeze in winter and cook in summer. People want to live in Atlanta instead of Buffalo no matter what I suggest.
Seattle conference/CC BY 2.0
The real epiphany for me came after I was asked to be a speaker at a Passive House conference in Seattle in June, and did a riff on my “in praise of the dumb home” thesis. In preparing my presentation I got to understand Passive House a lot better, and began to see it as another option beyond either living like grandma or living in a typical new house that needs to be air conditioned all the time- that architects and engineers had figured out how to build a house that doesn’t use much energy to either heat or cool, and that is comfortable. I got to tour a few of them, houses where occupants don’t have to freeze in winter and cook in summer but can still feel properly self-righteous because they are sipping heat and AC. I began to consider that maybe, if done right, air conditioning was not so horribly evil.
Aymar Embury II/Public Domain
Now, when I look back at Grandma's house that was designed to keep relatively cool in summer, I find that those features actually make it harder to heat in winter; the big windows, transoms, high ceilings, stack effect from basement to second floor all conspire to make corners colder, the whole house leakier and increase stratification between floors. That my beloved tuneable double hung windows are just about impossible to seal properly.
Also, when I ask myself what we have to do to build affordable housing in cities that can support transit and where you can get around by bike, I realize that we have to look for models that can scale. But it’s really hard to design apartments with cross-ventilation and even if you do, outside air quality is not so terrific either in many cities.
Then we have to acknowledge that the weather is getting hotter and stranger. In North America there is a temperate zone where the old techniques worked in most of the summer, but there are now long stretches where it is just too damn hot. As for the tricks that people used to do in Florida, the high ceilings and verandas, they never worked all that well, which is why very few people spent the summer there before air conditioning.
All of those techniques for keeping cool without air conditioning will ameliorate the situation but lets be honest and admit that that they don’t work all the time in all places.
© Saskatchewan conservation house then
Which brings me back to Passivhaus, the super-insulated house or even the Pretty Good House. The concept has been pitched as a way of saving energy, but the result is a comfortable environment. You get stable temperatures inside in both hot and cold climates because you are surrounded in a blanket of insulation and really good quality windows. The amount of heat or coolth needed is tiny, and heat pump technology has evolved so that the same equipment can provide both. So that technically, there is no reason not to be comfortable. It also scales, working in both houses and apartment buildings.
For years, I have railed against the green gizmo high tech approach to green, smart thermostats and net zero. Keep it simple and dumb. However there is really nothing simpler or dumber than a really thick blanket of insulation, decent windows, a tight envelope, and a ventilation system to deliver fresh air instead of getting it through the leaky walls and windows.
If we are going to get people out of their cars, build cities that are walkable, cycleable and desirable for families, there has to be housing that is comfortable, healthy and quiet. These days it also has to be resilient in the face of climate change and infrastructure breakdown. The way they built in Grandma’s day isn't going to cut it anymore.
Lloyd Alter/CC BY 2.0
I have been doing all this writing about living like Grandma from my own detached house shaded by a giant maple that I bought for less than the price of a studio condo today. Or from my cabin on the shore of a lake that I can jump into anytime I got hot, that I was able to buy for the price of a condo parking spot today. I got lucky. But I have two millennial kids who will never have that opportunity. So let’s get real and figure out solutions that can work for the majority of people, not the lucky boomers like me. Grandma might not like it, but my kids will.