More From Less: The Principle
Here’s some outdoor space. Judging by the colour of the brick, the teapot, and the underused barbeque in the corner, it looks like we’re in England. The peripheral plants are doing their evapotranspiration thing but those benefits won’t be needed much when the average summer temperature is 22°C (71.6 °F).
This outdoor space is enclosed by masonry on two sides and (almost certainly) timber on a third so any uncomfortable wind is probably blocked – along with any welcome breeze. We can’t tell the orientation from this image but, on evenings either side of summer, the thermal mass of the walls and paving will most likely make it possible to remain in this space for longer before someone suggests it’s maybe time you all went inside. But being outdoors is nice. There are many things we like to do outdoors whenever we can. The outdoor space in this next image seems to be in a climate that gets quite warm and, judging by the bamboo and the banana tree to the right, possibly quite humid as well.
Here, we can sit, eat and cook in this space, and even have a nap if we want. There are no walls and the floor is timber so there’ll be no heat retention due to thermal mass. The outdoor fireplace is probably something to look at whether functioning or not but it may help keep insects away. The absence of walls will allow any cooling effect a breeze brings. In this next image, one is protected from the wind and outdoor ambient temperature in this space which is external to the main building aesthetically, constructionally, and conceptually – so let’s have a barbeque then!
This space can be used when it’s not desirable to be outdoors, even if standing next to a source of heat. Basically, we’re still inside. It’s the barbeque that looks out of place. Indoors and outdoors remain very separate, but at least we have a better view of the outdoors.
A whole industry of conservatories and big glass doors and windows has developed to allow people to have a better view of whatever outdoor space they have even if it has to be appreciated next to a fireplace. Nice window!
Moreover, a whole universe of architectural endeavour has arisen to give the impression the outside of a building is really an extension of the inside, even if (or perhaps especially because) it can’t be used for most of the year.
The outdoor space in the image above benefits from wind protection and the high-mass surfaces will re-radiate absorbed heat in the evenings to extend the period of comfort further into the evening or autumn.
This next image is a photo of a Japanese house – actually it’s no ordinary house, it’s Katsura Palace doing the inside-outside thing that so impressed FLW and many other pre-21st and last-21st century architects such as John Pawson, designer of the space in the photo above.
As far as the internal environment is concerned, its a bit like this next space – a room without walls. Let’s play “Spot the Viking!” Both rooms are most certainly lovely to be in when the weather’s nice but, when it’s not, you really don’t want to be there. In passing, these two images show how thermal comfort is blind to notions of visual beauty. I’ll have more to say on this later but, perhaps one day there will be such a thing as tactile aesthetics – the beauty to be found in a physiologically comfortable internal environment.
But other than providing an alternative place to be when weather permits, what’s in all this for the indoor space? Nothing. We need to make a distinction between outdoor space that is no more than outdoor space the other side of a door or window, and outdoor space that also modifies the environment on the inside. Consider this balcony. It provides the benefit of additional space and the effect of adding value to the apartment but it will also provide the summer benefit of shading the glazing and modifying the thermal environment of the space that opens onto it – especially if the balcony faces south.
The thing about More From Less is that space that’s not fully enclosed and conditioned can substitute for indoor space some of the time and because it’s not enclosed to the same degree as internal space, can also provide climatic benefits for that internal space. In other words, space that isn’t constructed or detailed for 100% climatic adjustment can still passively benefit the internal environment.
Not all balconies, courtyards or rooftops have a positive passive effect. The courtyard of Ando’s Sumiyoshi House in Osaka will be hot in summer and cold in winter. Please visit this post on contraHABIT for a internal environment analysis of this house in terms of thermally active surfaces and flows, thermal comfort, natural ventilation, cross ventilation, stack effect and high mass cooling. (Nice work Taylor and good luck for the future!)
If not much in the way of climate control, Ando’s Sumiyoshi/Azuma House is a reminder of how the Japanese manage to aesthetically, if not always physically, appreciate a certain poetry in ambient temperatures lower than many of the rest of us might. When it gets too cold for their houses to do the inside-outside thing, you’ll find Japanese in warm clothes huddled around a source of heat before getting quickly beneath a stack of futons in a shiveringly cold rooms at night.
In this plan of a traditional farmhouse, Room 3 has an irori (see below) as a source of heat and most winter activity would take place in that room. Room 3 has no external walls. The remainder of the house is being used as a thermal buffer.
The vernacular housing of many countries will have similar examples of people retreating into the parts of the castle, mansion, or house that can be heated the most economically and efficiently. This sounds familiar. There might be something we can learn from this in terms of seasonally differentiated construction. Why should all of a house have to be used in the same way all the time and all through the year? After all, we all enjoy balconies but don’t expect to use them all year round. You’ve seen this plan before in It’s Not Rocket Science #7: Evapotranspiration. It’s the plan of an Egyptian courtyard house from around 3,000BC.
That post mentioned how cool air is trapped in the courtyard overnight to keep the spaces opening onto the courtyard cooler and cooler for longer into the day. It mentioned how this effect is reinforced by planting a tree in the courtyard to shade it. This works well in places with a large diurnal temperature difference.
This climatic benefit only arises because the central space is not fully enclosed. So if you’re going to read a book, or have a drink and a chat or possibly a nap, do it in the courtyard! Not everything needs to be done indoors all the time. The lesson here seems to be have two types of space. Climate permitting, the light structure can be dispensed with altogether.
The cave dwellings of northern China are another extreme example of this type of construction.
With these, there’s a heavy structure and huge thermal mass behind the building but this research shows that in front of the building it is still better to have a courtyard than nothing at all.
This reminds me of Villa Vals (46°37’15.49″N, 9°10’51.36″E) which, it seems, is now a rental villa. Its famous courtyard faces WNW – and another mountain. In this photo, we’re looking south, down the valley.
I don’t know if the courtyard at Villa Vals has a sufficient degree of closure to be a courtyard with any climatic benefits, but the principle is to have an outdoor area with a fair degree of enclosure fronting a structure with a higher thermal mass. The actual materials depend upon what’s available and the relative amounts of structures depend upon the climate. Temperate climates are easier to handle.
The rear half of the Lacaton & Vassal’s Latapie House is not a courtyard, but nor is it a covered porch added onto a house. And nor is it merely a covered part of the garden. Whatever it is, it is an inexpensive structure with the beneficial effect of extending the range of usable temperatures of what could have been conventional garden, further into the evenings and colder months. It ameliorates wind and temperature extremes and modifies the environment on a seasonal as well as a daily basis. It is not a courtyard but an inexpensive addition that produces climatic advantages not unlike those producedby courtyards in hot, arid climates – except that the object is to trap warmth, not coolth.
As is obvious from the plan, the house is not large, but this inexpensive addition permits a luxury of space and use that would not have been possible with more conventional materials and construction. The occupants have more options in terms of when and where to do what they do. Environmentally, the building has not used a wealth of resources. It is trapping heat to make its own volume more habitable and, even when it is unused, this effect carries over to thermally benefit the “main” building.
An earlier post mentioned how Lacaton & Vassal used this same principle in this project for an extension to a high-rise building.
This is a link to a paper titled “Building Performance Evaluation of Newly Built Greenhouse Residences in Terms of Heating Energy and Thermal Comfort”. These are some of its conclusions:
- A greenhouse saves about 25% on annual heating energy demand compared to a residence without greenhouse
- It is possible to optimise a GHR in such a manner that the greenhouse zone is usable for up to 750 hours a year, during 10 months
- The largest increase in usable time of the greenhouse zone compared to the outdoor climate occurs during the summer period
- A properly designed GHR does not exceed thermal comfort limits i.e. weighted overheating hours.
- The most sensitive parameters are related to heat gains/losses and insulation.In conclusion, we can say that a GHR has benefits in terms of annual heating energy demand and usable hours of the garden zone; nonetheless, highly insulating is more effective as it saves more heating energy. If a GHR is properly designed it is possible to reduce the annual heating energy demand with an acceptable thermal comfort and usable outdoor hours. It needs to be addressed that a GHR has the benefit of the outdoor space, in comparison to other building concepts.
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It’s a field of study that promises to pay off, particularly for buildings in temperate climates. In the past, people would enclose porches with lightweight structures in order to make more usable space. Well, in the future, more of what is called architecture just might have to include these lightweight structures that people will have to make the best use of whenever they can. And during extremes when that’s no longer possible, they can retreat into the core of the dwelling while the external structure serves to ameliorate that internal environment somewhat. Lacaton & Vassal are pioneers in that respect. It’s more useful than Sanaa elevating the communal circulation space to the status of architecture.
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So what about this then? What’s going on here?
Seoul Light DMC Tower Digital Media City in Seoul, Korea combines technology and sustainability strategies to create a new model of super tall building design.
A large central atrium spans vertically through hotel, residential and observation deck program areas to allow for penetration of natural light and air throughout the building.
Air rises through the atrium in a natural “stack effect” and drives wind turbines at the crown of the building. Interior gardens at perimeter atriums act as “lungs” for the tower, providing air circulation and filtration for the varied functions.
At 2,100 feet tall (133 stories), the mixed-use tower hosts a collection of green technologies, including solar panels, wind turbines, enhanced daylighting, and living walls. SOM anticipates that these strategies will reduce overall building energy use by 66 percent. “Original constraints on super-tall buildings were vertical transportation and structural requirements,” explains SOM design partner Mustafa Abadan. “Today, those requirements have become easier to solve with technological advancements, but sustainability needs to be addressed. We’ve shifted our priorities to environmental issues.”
Or how about this?
About halfway up the building at the hotel lobby, the more-traditional core is replaced by a 1,000-foot-tall vertical void. Roughly 60 feet wide by 100 feet long, the void is based on the principles of a solar updraft tower. Using the stack effect, air will be drawn into a collection area, where it will be heated naturally by the sun before it rises up through the tower to drive six horizontal-axis wind turbines, each 3 meters (about 10 feet) in diameter. SOM predicts that this “solar engine” will provide 3 to 5 percent of the building’s overall energy.
You can read more here, but I can’t help but wonder if this isn’t a lot of trouble to go to for a 3%–5% energy gain?
Enclosing space is expensive. “More From Less” is about inexpensive ways that space can be enclosed for limited amenity and limited climatic/energy benefit. Using less materials or construction or whatever BECAUSE it is better to do so. It’s quite simple really. This building of SOM’s does not feature lightweight steel framing and polycarbonate sheeting on the outside and which might have worked just as well. Instead, what we have is a large central void almost fully enclosed by some rather serious (and seriously contorted) structure. If the object is to create a column of air that can be heated, then this is over-construction. Why put a column of air in the middle of a building and then try to heat it from the outside? What were SOM thinking? I can’t believe an externally-mounted lightweight structure would not heat the air better and channel the hot air upwards just as effectively. Does it really take some swishy glass curves to make hot air go up? I find this building retrogressive in its use of maximum means to achieve not very much. The fact it won a a 2010 Chicago Athenaeum Green Good Design Award and a 2010 Eco-Structure Evergreen Award is deeply disturbing.
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This is a design study for a building that I did, way back in 1995, exploring the poetics of energy-saving technologies. The point was to make PV panels look all sexy by using technological grandstanding to make allusions to Nature. In other words, the point was to make a big show of representing renewable energy rather than concentrating on actually generating it.
Two huge triangular PV arrays are each mounted on three hydraulically-extendable columns that extend and retract to enable the orientation and inclination of the arrays to track the sun to a greater extent than would otherwise be possible. The array planes are always parallel except at around midday and just after sunset, when hydraulic manoeuvring has to rearrange them so the one at the back is now at the front, not unlike a butterfly refolding its wings.
The entire point of this study was to give poetic representation to renewable energy devices without regard for the initial cost, the amount of embedded energy or the amount of energy actually produced. It’s bullshit really – using devices of virtue for an architecture of decadence. It’s not unlike the eating of songbirds or the eyes of peacocks, but it’s where we’re still at.