The Passive House People

Germany's "passive houses" are attracting interest across the Atlantic, as Kevin Drum notes:

The concept of the passive house, pioneered in this city of 140,000 outside Frankfurt, approaches the challenge from a different angle. Using ultrathick insulation and complex doors and windows, the architect engineers a home encased in an airtight shell, so that barely any heat escapes and barely any cold seeps in. That means a passive house can be warmed not only by the sun, but also by the heat from appliances and even from occupants’ bodies.

....Decades ago, attempts at creating sealed solar-heated homes failed, because of stagnant air and mold. But new passive houses use an ingenious central ventilation system. The warm air going out passes side by side with clean, cold air coming in, exchanging heat with 90 percent efficiency.

....In Germany the added construction costs of passive houses are modest and, because of their growing popularity and an ever larger array of attractive off-the-shelf components, are shrinking.

But be warned: no McMansion for you!

Most passive houses allow about 500 square feet per person, a comfortable though not expansive living space. Mr. Hasper said people who wanted thousands of square feet per person should look for another design.

“Anyone who feels they need that much space to live,” he said, “well, that’s a different discussion.”

I've seen a few documentaries on passive houses, and they're really engineering marvels. I still really don't understand how a heat exchanger works, but apparently it does.

The only problem is that some of the passive house's acceptance can be chalked up to the way Northern Europeans (here, Germans) think:

1. Most Germans grew up in apartments or modest houses and are used to living in small spaces. Most have probably never had much more than 500 square feet of living space to themselves. Eng und wohl (snug and comfy) is the watchword here.
2. You often encounter Germans who have an amusing paranoia about drafts and a surprisingly high tolerance for (what I would call) stale, recycled air. To these people, hermetically sealed house = paradise.
3. The kind of Germans who could afford passive houses are the kind of Germans who care -- and want to be seen to care -- about the environment. For these people, a passive house is a status symbol.
4. I'd be willing to bet passive houses probably don't get quite as warm as houses with traditional heating. But Germans love nature, and don't like to mess too much with what it dishes out (witness the aversion to genetically-modified food). This helps explain the scarcity of air-conditioning in Germany, even in places which could easily afford it and where it might be pretty handy for 2 months of the year.

When summer comes around, Germans just sweat! In fact, they seem to kind of like sweating. They vacation in really hot parts of the earth, and frequently visit saunas, places in which you actually pay to sweat. This attitude is inexplicable to people who come from hot, moist parts of the world in which you have no choice but to sweat like a French whore, day-in and day-out, for 9 months of the year.

Comments

[curtis johnson realty]

This is a new technology in terms of housing. There is a great benefit having this kind of houses. This is more advisable during the winter or in cold places. Thanks a lot for the latest innovations in making houses. More power.

[tampa web hosting]

It has become a tradition for them same as the russians.

[chestnut uggs]

I recently visited friends who live in a passive house. It might not have been the extremely efficient variety,

[MonuMental]

I really can't agree with the notion that Germans like stale air. To me, it's just the opposite. When you go to school in Germany, the windows actually open, and ARE actually opened inbetween classes, to let in fresh air. Same at work, windows can be and are opened. In the states, you are lucky if you even have a window, and most of the time, it doesn't open. Instead, you get fake air out of the a/c system.
Anyway, those houses seem like an interesting concept, but I agree, they are probably mostly for people looking to show off how environmentally friendly they are...

[MonuMental]

I really can't agree with the notion that Germans like stale air. To me, it's just the opposite. When you go to school in Germany, the windows actually open, and ARE actually opened inbetween classes, to let in fresh air. Same at work, windows can be and are opened. In the states, you are lucky if you even have a window, and most of the time, it doesn't open. Instead, you get fake air out of the a/c system.
Anyway, those houses seem like an interesting concept, but I agree, they are probably mostly for people looking to show off how environmentally friendly they are...

[Johannes]

My heating bill is higher than 55/month for a small (but Altbau, badly insulated) flat... But it may be misleading a little, because as far as I know costs of building a house are very high in Germany anyway, compared to other countries. Of course, mostly you get something very solidly constructed for your money, but you must be able to shoulder the mortgage. And even if these houses don't look like UFOs nowadays, they may still be not to everyones taste. And there's the problem with the site, south-facing etc. But it's certainly worthwhile to build as many of these as possible. I'd rather not bet that these guys in CERN will be discovering a miraculous source of cheap unlimited energy, so Passivhäuser or at least Niedrigenergiehäuser are our best bet.

Johannes

[nanne]

The NYT report states that the added price for a home is around 5%. Say you have a mortgage of 1100 euros a month, then that would be 55 euros a month. For that money, you have zero heating costs.

What's your heating bill?

Energy passive houses, when constructed right, will also keep you cooler in the summer. Isolation can work two ways and theoretically, the heat exchanger can, too.

In the future having a heat exchanger as well as a solar heating/cooling system for showers and temperature regulation will become standard for all new houses and a lot of old ones.

[Visitor]

It is not that Germans like to sweat.
One problem with air conditioning is that whenever you enter a building just for a short time, say you want to buy a sweat shirt, and leave again, lots of people get a cold. I went to L.A. in summer. I rented a car (air conditioned), I visited some shopping malls, and I got sick! It is the same in winter in Germany: Most rooms are overheated. Older People seem to enjoy this. But it is easier to open your jacket and I do it without a thought these days.

[Alphager]

Point 4 is wrong: passive houses get mighty warm.
When visiting a friend, he had to open a window to cool the house down to 23°C because my added body-heat and the sun combined were to warm.

[Johannes]

I recently visited friends who live in a passive house. It might not have been the extremely efficient variety, though, because I think they had some central heating. And they were using a humidifying device or something like that in winter, because otherwise the air gets to dry.
But it was neither cold nor stale (certainly not compared to the drafty Altbau flat I live in now). It also was reasonably spacious for two adults and two (7 and 9 yo) kids. They aren't particularly green either (both parents have economics degrees and their cars didn't seem green to me...)
Sorry I can't contribute more details, I'll ask them the next time around.

A heat exchanger should just be something like two tubes (with many turns) inside each other. While the hot air streams along one tube and the cold air along the other one, they exchange heat. (It's technically probably quite difficult to realize with air, but the principle should be the same as with liquids.)

Johannes