The many ways of airing out the room

October 2, 2020 8:11 AM

German has distinct verb combinations for airing out flats and recommendations are getting more and more precise.

"Impact ventilation, or Stosslüften, which needs explanation for most people unfamiliar with Germany except for experts in air hygiene, involves widely opening a window in the morning and evening for at least five minutes to allow the air to circulate. Even more efficient is Querlüften, or cross ventilation, whereby all the windows in a house or apartment are opened letting stale air flow out and fresh air come in."

There is als Durchlüften, Auslüften, Kipplüftung and Dauerlüftung. There might be more. We just really like opening our windows in many ways.

posted by katta (45 comments total)

I'm glad the article specifically mentioned German window hardware, which is awesome.
posted by Slothrup at 8:21 AM on October 2, 2020 [9 favorites]

Agreed! German tilt/turn windows are amazing things, I can see why they want to mess with them all day long.
posted by JoeZydeco at 8:22 AM on October 2, 2020 [15 favorites]

I live in Germany and this has been the bane of my life. In Norway my windows would go in any direction so you could have air going in or out and houses generally had small airing vents you could open for a less aggressive air exchange. In Germany all the windows I’ve come across only tilt inward and open fully inward. So to exchange the air you have to have more than one window open on different sides of the house (I think?) otherwise you just get fresh air in But nothing out and once you close the window whatever smell was bothering you is still there. If you have windows cracked inward and someone is smoking outside then all the smoke gets sucked right in your house. I miss being able to crack a window a little bit all day long. I miss being able to put things on my window sill. When we moved into this house we received a very long several page booklet of instructions about how to exchange the air and we had to promise to do it twice a day for ten minutes- all the windows open fully in the whole house, even in the depths of winter. I can totally see how this is good but it’s not so easy and I wish I had more ventilation options.
posted by pairofshades at 8:38 AM on October 2, 2020 [5 favorites]

otherwise you just get fresh air in But nothing out

If air is coming in, it must also be going out right? Unless your house is inflating.
posted by EndsOfInvention at 8:46 AM on October 2, 2020 [14 favorites]

I just find it’s really tough to air a room out unless you do the full routine. So when my kids were babies and had a smelly diaper and I tilted the window for five minutes... as soon as I shut the window it still smelled like a dirty diaper. In those cases I would very much prefer to crack a regular window for a longer period of time... or make use of a fan or something but you just don’t have those options. There is no such thing as gentle airflow. German windows are just really intense.
posted by pairofshades at 8:56 AM on October 2, 2020

for at least five minutes to allow the air to circulate

Coming from an open-window culture, I'm always amazed by ideas like this. 5 minutes does so little. Stale air smells so bad. Even if I'm keeping windows closed most of the day for temperature control, I'll still try to keep things open for the largest possible intervals even if it means being a bit uncomfortable for a while. Might not be possible in really extreme climates, but I don't think Germany is there.
posted by trig at 9:12 AM on October 2, 2020 [4 favorites]

If air is coming in, it must also be going out right? Unless your house is inflating.

Incidentally, the German term for “inflatable house” is ein aufblasbares Haus.
posted by ricochet biscuit at 9:15 AM on October 2, 2020 [6 favorites]

This thread went from airing out the house to airing out the grievances faster than I would have expected.
posted by mhoye at 9:18 AM on October 2, 2020 [23 favorites]

If air is coming in, it must also be going out right? Unless your house is inflating.

The term you're looking for is make-up air (my brother is an an HVAC engineer so I've gotten this lecture a whole bunch of times).
posted by mandolin conspiracy at 9:30 AM on October 2, 2020 [4 favorites]

This thread went from airing out the house to airing out the grievances faster than I would have expected.

You should probably recalibrate your expectations for threads involving Germans.
posted by Ryvar at 9:33 AM on October 2, 2020 [9 favorites]

What's old is new again. In response the Spanish Flu epidemic, new heating systems in most NYC buildings were deliberately overengineered so residents would be forced to open the windows during the winter months. Lots of older apartments (build < 1930ish) still have absolutely bananas big radiators.
posted by voiceofreason at 9:34 AM on October 2, 2020 [11 favorites]

There were also "tuberculosis windows" in New York tenement buildings that were more sanitation theatre than effective measure:

Landlords figured it was cheaper to install an interior window rather than design an apartment building with real windows in every room that actually allowed for decent air flow.

You can see one in the scenes of Vito and Carmela Corleone's tenement apartment in Godfather II.
posted by mandolin conspiracy at 9:38 AM on October 2, 2020 [5 favorites]

Warning: the article does not provide a 12-syllable German word for disinfecting a room by vigorously opening the windows. Not sure if there's any other reason to read it.
posted by morspin at 10:16 AM on October 2, 2020 [6 favorites]

That's the joy of German! You can glue any set of words together to make your own.

RegierungempfohlenstoßLuftmaßnahme: "Government recommended push air action"
posted by JoeZydeco at 10:30 AM on October 2, 2020 [8 favorites]

A typical scenario in Germany is someone opening the window in an office or on a train, say, then the next person comes in and complains it’s draughty – that’s another German obsession – and insists on closing it.

As the thread has shown already - in Germany, air moving around in rooms is the source of no small amount of emotion.
posted by From Bklyn at 11:01 AM on October 2, 2020 [3 favorites]

I still remember being horrified and impressed when the German family I stayed with the Black Forest flung the bedroom windows open in the morning when it was -25C outside. Because it's *healthy*. My host mother would sleep with the windows open in winter. Crazy.
posted by i_am_joe's_spleen at 11:44 AM on October 2, 2020 [5 favorites]

I was surprised to learn about this, since previously I have read that many Germans feel that drafts are unhealthy in situations where I (an American) would cheerfully open a window. Like if you're stuck in a car without AC in traffic in the summer.

But it is true that CO2 levels can be surprisingly high in an office, house, or school with modern insulation and no other source of ventilation. I try to crack a window for at least 10-15 minutes a day, especially if I'm feeling drowsy.

These days I live in the Pacific Northwest where you can reliably air out the house a bit even in the middle of winter. Different story when I was a kid growing up in Alaska. We had that shrink wrap cellophane stuff over the windows all winter long to keep the heat in. Plus my mom smoked a pack a day. She had a hilariously inadequate air filter unit about the size of a loaf of bread. Just one, for the whole house. I remember walking through a haze of cigarette smoke that built up in layers to the ceiling. Ahh, the 80s!

Oof I just placeboed myself into feeling stuffy, I'm going to go open all the windows in the house now!
posted by ErikaB at 11:47 AM on October 2, 2020 [9 favorites]

Get a house to air out with windows is still close to magic in my opinion, at least on the first floor. The wind has to be blasting and the room has to be surprisingly narrow, or the air flow will be close to nothing and doing an air exchange will take hours. Compared to a central A/C that changes air 6-9 times per hour while running, if I can get one air change per hour through windows, I'm generally surprised.

This article says an average air exchange rate with open windows is close to 2 per hour (I think, not 100% expert at science writing).
Nature.com air exchange test
posted by The_Vegetables at 12:04 PM on October 2, 2020 [2 favorites]

I am a room-airer by upbringing and temperament, and I like the place I live because it was built to make that easy - doublehung windows, the only large clothes closet has a little openable window, for instance. But it’s also more than a hundred years old and whenever I hear of engineering improvements to airing I’m happy.

I got crossways with a bunch of U.K. people a while ago because they were sure air drying clothes indoors put no additional load on their heating systems. (Physically impossible - evaporation is energy intensive.) Turned out they all had energy recovery or heat recovery ventilators, mostly retrofitted, so indoors line drying was a small enough total energy cost they could not notice it. Also that conversation made clear how crazy energy-gulping the standard US dryer is. And then! During the Smoke, with our windows shut and the heat off, the house was getting damp and I didn’t want to line dry in the smoke or use our standard dryer and pull air into the house.

I want a MERV.
posted by clew at 12:37 PM on October 2, 2020 [2 favorites]

MERV is a rating for air filters. You mean ERV, right?

I want one too
posted by JoeZydeco at 1:06 PM on October 2, 2020

This is so funny. The article reads as completely straightforward to the point of redundancy to me. Like, doesn't every language have words for querlüften and stoßlüften?
Are there offices where people don't wage regular winter wars about lüften vs. Zug?
posted by Omnomnom at 1:19 PM on October 2, 2020 [1 favorite]

I do! Anyway, one of the elegant countercurrent heat exchangers that does whatever the appropriate thing is with humidity. Whatever they’re called where I am.
posted by clew at 1:19 PM on October 2, 2020 [1 favorite]

Omnomnom, I would guess that the modal US office has no user-openable windows.
posted by clew at 1:20 PM on October 2, 2020 [4 favorites]

Not only are the windows sealed but the thermostats are fake.
posted by JoeZydeco at 1:26 PM on October 2, 2020 [7 favorites]

Handelsblatt explains the German fear of Durchzug
posted by Omnomnom at 1:28 PM on October 2, 2020 [3 favorites]

The_Vegetables, as I read it that paper says opening windows replaced indoors air twice as fast as running the attic fan and much faster than the HVAC fan did. I notice it’s a tall townhouse - maybe it gets a chimney effect going.

I was surprised that they found well-mixed indoors air. I’d figured any corner that hatches dust bunnies is a corner with slow air movement.
posted by clew at 2:07 PM on October 2, 2020

I live in the Pacific Northwest where you can reliably air out the house a bit even in the middle of winter

But not in August, not anymore, cough cough...
posted by justsomebodythatyouusedtoknow at 4:38 PM on October 2, 2020 [3 favorites]

We have an old house with a whole house fan that is freaking scarey. It’s in a long hallway to the bedrooms and if you turn it on with only one of the doors open, that door will slam shut fast and loud , so you need to make sure plenty of doors and windows are open. There is a lower fan speed you can use but that’s not my style. The entire house can be aired out in a few minutes. Not sure why these things went to the wayside.
posted by waving at 8:09 PM on October 2, 2020 [3 favorites]

My dad’s house had a whole house fan too. It’s like an airplane propeller in the ceiling, loud as hell, and you better believe it’ll blast the hot air out of the house in short order. I’ve wondered how easily we might retrofit one in our place.
posted by schoolgirl report at 9:27 PM on October 2, 2020

Whole house fans are still around and are great in the right climate. I too don't know why they aren't more widely used.
posted by medusa at 3:57 AM on October 3, 2020

I live in Germany, and while I kind of understand the obsession of airing out buildings, I cannot understand why fans in summer are uncommon. Air conditioning anywhere is rare and I get that people are against it for energy/environmental reasons. But pedestal and table fans are nearly non-existant. It's only the past couple years of sweltering summers that people are starting to adopt them (including my office, which reached 34 degrees Celsius indoors this summer).

So, blasting a current of winter air through the building twice a day = absolutely. Creating a slight breeze with a fan in the heat of summer... slowly catching on but held with suspicion.

Anyways, I have become the crazy opening windows lady with this whole corona thing. It's this damn virus that FINALLY has me integrating :D
posted by exquisite_deluxe at 3:59 AM on October 3, 2020 [3 favorites]

From the Handelsblatt article linked above:

Jörg Kachelmann, a Swiss meteorologist and journalist, recently railed against the myth of Durchzug, which he believes German immigrants imported to his country. .... “When you encounter Germans who cry Durchzug, discuss deportation with them, as this superstition threatens the health of many people in our country,” he wrote.

Didn't really expect that sudden xenophobic/racist connection at the end of an article about drafts.... !
posted by thefool at 6:03 AM on October 3, 2020

Whoa, I completely misread that bit for some reason. Sorry to subject you guys to that. The immigrant connection is ridiculous.
posted by Omnomnom at 6:18 AM on October 3, 2020

"I still remember being horrified and impressed when the German family I stayed with the Black Forest flung the bedroom windows open in the morning when it was -25C outside. Because it's *healthy*. My host mother would sleep with the windows open in winter. Crazy."

It me! I grew up not too far from the Black Forest and I hate sleeping in heated rooms and/or with closed windows. Give me a warm blanket and an open window even if my breath turns into icicles!!! I also open every window wide in the morning for some nice durchlüften. I have come to appreciate ACs now that I live in LA and even more so with WFH but it's not like they're bringing in fresh air.
posted by Hairy Lobster at 11:29 AM on October 3, 2020 [2 favorites]

The immigration connection is because it's a very Slavic superstition to avoid drafts (you still open windows, just one at a time), possibly because we used to be damper/more swampy, so there was a good chance you're sitting indoors still wet from the outdoors. Read: anyone who fears drafts is a dirty Pole and should be extradited if not for the pesky Schengen area thing. Yay intra-European discrimination.
posted by I claim sanctuary at 11:47 AM on October 3, 2020 [1 favorite]

Whole house fans are still around and are great in the right climate. I too don't know why they aren't more widely used.

AIUI: National building codes that aren’t always adapted for regional conditions, also stuff built with national economies of scale is cheaper. Plus so many people move between regions and want what they’re familiar with. Plus a taste for systems that maintain constant indoors conditions with no user attention - I think this is an aesthetic choice as much as an efficiency one, but an architect has told me that it’s the assumed perfect building. IIRC "thermal delight" is a phrase from the counter-movement.
posted by clew at 12:37 PM on October 3, 2020 [1 favorite]

You write

I cannot understand why fans in summer are uncommon

and

It's only the past couple years of sweltering summers that people are starting to adopt them

You've answered your own question. Summers are hotter in Germany than before. People didn't need air conditioning before. I'm excited to see how people will adapt. Maybe siestas will become popular :)
posted by starfishprime at 9:25 PM on October 3, 2020

thermal delight
posted by away for regrooving at 10:46 PM on October 3, 2020 [1 favorite]

Didn't really expect that sudden xenophobic/racist connection at the end of an article about drafts.... !

Read: anyone who fears drafts is a dirty Pole and should be extradited if not for the pesky Schengen area thing.

My reading of the quote is that the Swiss doctor doesn't like that the Germans have brought this thinking into his country (where I guess according to him, this is not normal). I thought it was a good natured neighborly ribbing, not actual xenophobia?

Anyways...
Opening the windows here I totally get. If there is no forced air heating/cooling, there's no way for fresh air to enter your house. Even I, someone who wears a sweater if it less than 90 outside, will keep my windows open for at least a little bit every day.

Germans in general have quite interesting ideas of what affects your health: winds (specifically the ones from Italy that are dry after going over the alps), air conditioning is bad for you, sitting on a cold surface can give you a UTI (whether its true or not, I never heard this in the US ever), sudden changes in weather (i.e. big temp drop) will cause all kind of issues for people. I feel like its alot of those old wives tales that never really went away, and doctors here actually follow them as well.
posted by LizBoBiz at 2:00 AM on October 5, 2020 [2 favorites]

Even more efficient is Querlüften, or cross ventilation, whereby all the windows in a house or apartment are opened letting stale air flow out and fresh air come in."

In Swedish it's korsdrag, literally "cross draft". Opening more than one window in more than one place in a home to air it out, isn't that a common thing in most parts of the world that aren't damp?

I love the tilt-turn windows, such flexibility! I wish they'd open outwards, but maybe that's a design constraint? They weigh quite a bit with all that proper insulation and might damage the window frame in high windows if they opened outwards.

I can't find any source that they originated in Germany other than "this right here is some fine German engineering" marketing speech. Anyone know if they're indeed German originally?
posted by Dee Grim at 7:00 AM on October 5, 2020

I wish they'd open outwards, but maybe that's a design constraint?

They'd interfere with the rolladen, the other wonderful component of a German home.
posted by JoeZydeco at 7:16 AM on October 5, 2020 [3 favorites]

Whoa! Is the rolladen just for darkness? Is it also a storm shutter? Do they ice shut? I’ve seen similar things as fire shutters, but I don’t think of that as a major German concern?
posted by clew at 3:02 PM on October 5, 2020 [1 favorite]

Oh man, we also have tilt-turn windows in The Netherlands and it drives me mad that they're not common in the UK. Maybe to fit in with the generally bad condition of the housing stock.
posted by atrazine at 6:44 AM on October 6, 2020

Whoa! Is the rolladen just for darkness? Is it also a storm shutter? Do they ice shut? I’ve seen similar things as fire shutters, but I don’t think of that as a major German concern?

The part about Rolladen I miss the most here in LA is that they block heat outside the window, not trap it inside like the blinds we got here
posted by Hairy Lobster at 1:46 PM on October 6, 2020 [3 favorites]

> sitting on a cold surface can give you a UTI (whether its true or not, I never heard this in the US ever)

Ooh, I was told this by teachers when I was a kid in Finland and we'd sit on the stone steps at recess.
posted by The corpse in the library at 6:17 PM on October 6, 2020