Heliotropic buildings, skyscrapers with vibration absorbers, walls with integrated phase selectors, dancing facades, moving walls, and buildings that are bigger inside than out – 21st-century architecture is interactive. And very much alive.
We like to take for granted the enormous variety of specific architectural solutions for the places where we live and breathe and work: from the igloo to the tent in the desert, the bunker to the space station. But we still have a stereotypical image in our minds when we hear the word "building": static, passive and universal. However, buildings intended to cope with today's lifestyles are (we hope!) changeable and adapted to specific circumstances, or even customisable in themselves. And they need to be, as they do not all face the same demands in every location.
Whether it be the climate, potential (natural) risks, the setting for the buildings (surrounding landscape, architecture or culture), their purpose and function, symbolic expression and aesthetic requirements, energy aspects, mobility needs, the space they need, building regulations – there are a host of challenges. This is especially true whenever buildings are expected to respond interactively to the life they accommodate even after they have been "completed".
… because throughout the history of architecture, problems and priorities may have changed but the same structural solution can still work for different starting points. Take a specific example: buildings on stilts. Although the main reason for their existence has long been to protect their inhabitants from wild animals, enemies and flood waters, you will still find today in city centres – far removed from such dangers – buildings standing on pillars. Now they are meant to create an open space below a building to meet and interact with others. This is a way for buildings to react to the restricted space available in today’s cities and meet the needs of their residents.
There are also places where the problems are the same as they have ever been, but where the solutions vary from the traditional to the modern. When Nias Island near Sumatra was hit by major earthquakes in 2005, nearly all of the buildings collapsed – except those that had followed tradition when they were built. Their locations on hilltops and their construction on three levels (substructure, coherently constructed living space and a very high light roof) were ideally adapted to the local danger of earthquakes.
These days earthquake-prone areas make successful use of flexible foundations and building materials that can bend under high pressure. Vibration absorbers are used in skyscrapers. That is why a huge ball weighing 660 tons hangs from steel cords on the top floors of the 508-metre high Taipei 101 Tower in Taiwan, acting as a pendulum by swinging in the opposite direction to movements caused by earth tremors. This counters dangerous vibrations and prevents the building from falling down.
It really starts to get exciting when architecture deals with constantly changing surroundings: this is when buildings suddenly start to respond to specific data provided by sensors on measurable and, above all, changing conditions in the environment, the weather, etc. – and then transform themselves accordingly. Obviously to the benefit of those inside.
Let us look at a relatively simple example, such as heat insulation. One well-proven material for this purpose is clay, as it has a high capacity for storing heat and evens out the temperature: during the day it absorbs heat, which it then releases overnight. This keeps rooms cool in the summer and creates a pleasant indoor climate. The insulation features of clay can be further improved by adding straw to it. In southern climates, clay (adobe) buildings may be found everywhere – not least because clay is easily available.
Massive concrete or masonry walls also have a high thermal storage capacity and a corresponding cushioning effect. However, since buildings are increasingly of light construction (wood, steel or glass instead of concrete or stone) and have large areas covered by windows, there is insufficient thermal mass to prevent them from overheating. Of course, they can be cooled with air conditioning but that consumes a lot of energy.
The latest solution is called PCM (Phase Change Material). Microencapsulated PCMs (such as types of paraffin) are integrated into conventional building materials like plaster and spread onto the surfaces of walls and ceilings. The trick with PCMs? When a particular temperature is reached (say, 26°C), the material changes from solid to liquid while maintaining its own temperature. It takes the necessary energy from the surrounding heat and thus stabilises the temperature in the room. In this phase of the conversion, large amounts of heat are taken in and stored (latent heat). When the surrounding temperature cools down at night, the PCM returns to its solid state, releases its stored heat and is ready to be "recharged".
There are other ways that buildings can change, such as at the Centre for Molecular Medicine at the University of Cologne or Kiefer technic’s showroom in Bad Gleichenberg. Their facades are covered with horizontal metal boxes that offer protection from light and sunshine. When all the windows are closed, the building looks like a warehouse without any kind of window. When they are open, the character of the building changes completely, welcoming all and sundry. This not only allows them to adapt to the sun’s rays but also provides the desired aesthetic effect. At Kiefer technic, the aluminium boxes can each be switched up or down gradually and changes in movement can be programmed, with the effect that the façade appears to be dancing.
Equally aesthetic and at the same time energy efficient are photovoltaic systems integrated into buildings. A moveable solar shield is planned for the Burj Al Taqa Energy Tower in Dubai, although it has not (yet) been installed owing to the financial crisis: it will simultaneously provide shade and generate electricity as it revolves with the sun around the 322-metre skyscraper.
Not only individual elements can adjust with the sun’s movement: whole buildings can do this and have been doing so since the first half of the 20th century. This was a time when solar therapy was growing in importance and so hospitals and homes were built that let in direct sunlight throughout the day. Belgium’s François Massau built his second revolving house so that his sick wife could enjoy warmth and sunshine all the time. The rotations did not automatically follow the sun but could be controlled by a machine.
A more recent example that is considered as the hallmark of solar architecture today is the Heliotrop, a revolving solar building in Freiburg. This is a cylindrical building standing on a single pillar. It is covered in glass on one side and solid, as well as insulated, on the other. The rotations ensure that the glazed side is always facing the sun.
Even skyscrapers can revolve on their own axis. The Suite Vollard, which opened in 2001 in Curitiba, Brazil, was the first. This is not primarily a question of facing the sun but of the view that the apartment residents wish to look at. Eleven of the fifteen storeys can be moved independently in either direction.
Revolving towers are also being planned in Dubai of which at least a number of floors can be adapted to the views desired by the residents. These include the Rotating or Dynamic Tower. The gigantic building concept – what else would you expect in Dubai? – by David Fisher already received numerous awards in 2008, although the construction keeps being postponed.
Also moveable but in a different way is the Whangapoua Prefab Hut, an elegant multi-storey beach cottage on the New Zealand peninsula of Coromandel. Two runners enable the building to be "re-parked" – not just for fun but as a necessary adjustment to the constantly changing landscape in an area noted for its coastal erosion. The hut is also adapted to wind and weather with its big opening/closing front and windows.
The Swedish architects Jägnefält Milton designed an even more unusual and exciting concept for the Norwegian town of Åndalsnes: the "Rolling Masterplan" – buildings on rails. The widespread rail network, previously used for industrial purposes, provides the infrastructure for these mobile buildings. Depending on the season and situation, the buildings can be rolled through the town and its surroundings, which are impressive not just to tourists. They are mostly built as small, boxlike houses or rooms, yet a moving hotel is conceivable, as is a public swimming pool and a concert hall. This is a concept that is tailor-made for the existing circumstances and the architects say it can easily be implemented.
In some cases you might think there is simply too little room to construct a building. Not if you are Centrala’s architect Jakub Szczęsny. He has squeezed the narrowest house in the world into a gap ranging from 72-133 cm between two existing Warsaw buildings. A hallway, a compact kitchen, a little bathroom and a bedroom with a desk can be reached via steps and a ladder. The ceiling and walls are made of polycarbonate plates that are thin and transparent – essential for the "somewhat" tight location between the two neighbouring buildings. The building has 14m² of floor space but is not intended to be a complete flat: it was in fact designed as a studio for the Israeli author Etgar Keret, who occupied it in 2012.
There are lots of places where restricted space is an issue – all of the necessary rooms will simply not fit. This is because, apart from the functional units such as bathtub, bed or kitchen units, everyone needs a bit of free space to avoid feeling that they are packed in like sardines. The celebrity designer Luigi Colani has come up with one solution with his Hanse-Colani-Rotorhaus, which is on show in Oberleichtersbach near Fulda: there is a space in one corner containing a bath, bed and kitchen, which can be rotated depending on what the user wants at any one time. The remaining free space is shared by all the "rooms", thus making 75m² of living space out of a total area of 36m².
Architect Gary Chang makes do with even less space in his 32m² Hong Kong apartment. It only has one room but it can be transformed into 24 different ones. This is because the interior walls can be moved across tracks in the ceiling. The functions of the various rooms are integrated into the walls and can either be accessed immediately after moving the walls, by folding down an element or through similar easy movements. The room thus changes to meet one’s needs: a thoroughly flexible solution for the usually tiny apartments in the overpopulated city of Hong Kong.
In another design by Gary Chang – the Suitcase House – it is not (just) the walls but also the floor that reveal unsuspected opportunities. By lifting various panels in the floor, you can find a kitchenette, a shower tray, a bed or plenty of other "rooms" buried in hollow spaces a few steps under the floor. So it is very simple to adapt the interior to one’s individual needs.