It’s sunny and 85 degrees outside (30 degrees C), and even the ducks are listless and miserable. My Texan friends might laugh, but stop to think about this first: Germany has almost no air conditioning! Everywhere you go right now, from stores to restaurants, you’re unlikely to find that chilly blast of refreshing A/C we Texans take for granted.
The first time Joe and I moved to Germany, it was already September, and summertime heat was the last thing on our minds. When we picked our first house, we didn’t think to ask about the prevailing breezes, and we weren’t sorry the house didn’t have a basement. Passive solar? Sure, we’d heard the phrase–but we hadn’t ever had to live it.
We spent some desperately uncomfortable days and nights in that house.
The truth is that the average house in our part of Germany doesn’t need air conditioning. It has features that, if properly used, can help keep its residents cool. The walls are cinderblock, with stucco on top of that. They’re at least a foot thick. Windows in most well-made houses are equipped with Rollladens (yes, all three of those Ls belong there). Rollladens are special shutters that roll down outside the window glass. They can be rolled down in such a way that they let in some light, like these Rollladens in my dining room:
Or they can be closed entirely, like the Rollladen over this window in my library:
Rollladens help immensely to keep a German house cool. By keeping sunlight off the window glass, they stop that “hot car” greenhouse effect. They also trap dead air and insulate the window area from heat. In effect, they turn my windows into more of that lovely, thick German wall.
Every window downstairs is shut tight against the higher temperature outside. But heat rises, so upstairs, I’m letting the breezes blow through to keep any warm air from getting trapped. This house’s second story has large patio-door-style windows at each gable end, and they stand open day and night. The house also has four large windows in the roof, and they’re open as far as possible to let the rising hot air escape.
My house would seem to be doomed to be an oven because an entire south-facing room is glass without proper Rollladens:
And a large part of the roof is glass, too. (Thank God, it has polarized window film on it.)
Because I take advantage of the other features of the house, however, even the room right next to all this glass is cooler than the outside air. The thermometer on the desk in the library tells me it’s 78 degrees (26 Celsius) right now, seven degrees cooler than the temperature in my sunny garden outside.
But, on an ordinary day, I wouldn’t be in this room at all. I would be taking advantage of the best passive solar feature this house has to offer: a full basement apartment.
The first time we house-hunted, we didn’t give basements a second thought. By the time we got to this, our third house, we walked into the basement and said, “Great! This is where the guest beds go and where the writing workstation goes. This is where we’ll escape in the summer.” Right now, all the Rollladens are closed on the half-height basement windows downstairs, and Joe is lounging on one of those guest beds in the twilight, surfing the web on his tablet. The room feels almost too cold. That’s because the temperature down there is 73 degrees.
That’s right: it’s five o’clock in the afternoon on a clear summer day, and a whole section of this un-air-conditioned house is twelve degrees colder than the outside air!
In the winter, that basement apartment is also the warmest place in the house. Its living room is a big, clean, plain room without pictures or distractions, and that’s where I do my writing:
The big cinderblock walls of my German house are heating up right now, but tonight the temperature is scheduled to drop down to 59 degrees (15 Celsius), and I’ll keep the second story windows open all night to let today’s heat radiate out of here. If the heat wave continues for several days, even the basement will slowly lose its cool, but that’s unusual in Germany. Tomorrow is forecast to reach a high of only 71 degrees (22 Celsius). I’ll open all the windows in the house to let as much of that chilly air as possible reach both sides of my German walls, getting them ready to battle the next heat wave… whenever it comes along.
To read my latest blog posts, please click on the “Green and Pleasant Land” logo at the top of this page. All photos taken in 2013 and 2014 in Rodenbach, Germany, except for the duck, which was photographed in June, 2014, in Lindau am Bodensee, Germany. Photos and text copyright 2014 by Clare B. Dunkle.