Clements-Croome Designing Buildings for People

Sustainable liveable architecture
1. Auflage 2020
ISBN: 978-1-78500-710-1
Verlag: Crowood
Format: EPUB
Kopierschutz: 6 - ePub Watermark

E-Book, Englisch, 208 Seiten

Our built environments can affect us in many subtle ways. Simply sensing fresh air and natural light or seeing greenery and open space can uplift our mood and improve our wellbeing. But these healthy environments are increasingly difficult to achieve in practice. The vital collaboration between the many people involved in designing and producing buildings is often not achieved. Then there is the pressing need to reduce waste and pollution. Managing these demands is a challenge, especially in a traditional climate of short-term thinking. Designing Buildings for People explores how we can learn from buildings of the past, vernacular architecture and the natural world around us, while still harnessing the opportunities presented by technology, to think creatively, work collaboratively and exercise a transdisciplinary approach. The book features over 200 images, exhibiting the acclaimed work of internationally recognized and research-led designers from the fields of architecture, engineering and management. It is a prime reference work for professionals and students who want to build the sustainable buildings of the future.

Derek Clements-Croome began his career in industry before entering academic life. He has carried out research and teaching in departments covering architecture, engineering, human sciences and management. Presently he is Professor Emeritus at the University of Reading and a Visiting Professor at Queen Mary University London, besides collaborating closely with the British Council for Offices.

Autoren/Hrsg.

Clements-Croome, Derek

Leseproben

Chapter Two

Vernacular architecture

If we look at all the major concerns of humanists and environmentalists today: balanced ecosystems, recycling of waste products, people’s participation, appropriate life-styles, indigenous technology, etc. we find the people of Asia already have it all… The old architecture – especially the vernacular – has much to teach us as it always develops a typology of fundamental common sense.

Charles Correa

MANY LESSONS CAN BE LEARNED by studying vernacular architecture (Oliver, 2003)1. The term ‘vernacular’ has been used since the 1850s by architectural historians to refer to the native architectural language of a region. Vernacular architecture has evolved from early humans living in caves or trees, to nomadic peoples using wood, wool and plant materials to make portable tents or yurts. And there are animals who make their homes in a myriad of ways to suit their needs, however hostile the environment. Vernacular architecture blends buildings into their specific settings, so that there is a natural harmony between the climate, architecture, and people. It features natural ventilation and controls air quality with the careful design and placement of indoor pollutant sources like stoves and commodes. Three examples of effective vernacular architecture are described in this chapter: wind towers, courtyards and igloos – each integrating the conditioning power of natural ventilation to give unique responses to local climate.

Some new buildings imitate the best of mature buildings; they increase in sophistication while retaining the simplicity that is a hallmark of vernacular architecture. Lim Jee Yuan describes in his book (1987) how it creates a nearly perfect solution for the control of climate, with a multi-functional use of space, flexibility in design and a sophisticated prefabricated system which can extend the house with the growing needs of the family. There are many examples worldwide of how humans have ingeniously designed buildings to respond to climate; the principles upon which they were conceived are still relevant today.

Fig. 2.1 A traditional Malay house. (a) Natural ventilation and stack effect diagram of Selangor traditional Malay house (Ramli, 2012, available via licence: CC BY-NCSA 4.0); (b) Malaysian traditional architecture. (Photo: http://davidvso.blogspot.com/2012/09/east-coast-trip_20.html); (c) Fenestration design of the Selangor traditional Malay house. (Ramli, 2012, Available via licence: CC BY-NC-SA 4.0)

People in countries throughout the world have shown that there are many ways of creating buildings that not only provide an enduring practical utility but also an aesthetic; Islamic architecture is one example that is renowned. Currently there is a danger that as the economy of nations becomes more reliant on the rapidly advancing technologies, lessons enshrined in the heritage of world architecture will be neglected and a solely modern technological approach adopted. The basis of this chapter is to argue that human and sustainable development are the main priorities. Buildings should enrich the lives of people and for this they need to be in harmony with the climate, the purposes for which they are built, and the culture that has evolved in their region.

One strength of vernacular architecture is that it blends buildings into various settings, so that there is a natural harmony between climate, architecture and people. In countries such as Iran, Iraq and Egypt, buildings have evolved which not only demonstrate this harmony and unity between people and their environment but also combine engineering and architecture with functional and aesthetic qualities.

Over the ages people have used their ingenuity to make habitats safe, warm and weather protected: the troglodytic architecture sculpted out of the hillside landscapes of Morocco; the igloos of the Inuit people; African courtyard houses; the Malaysian tree-dwellings; the English thatched cottage – and many more – are designed such that the inhabitants can withstand the hot or cold, the dry or humid rigours of the regional climate. Besides their orientation, the mass, built form and materials chosen for these habitats play an important role in vernacular architecture and characterize its style to suit the culture and local climate with an economic use of resources.

Buildings in cold climates must offer protection against wind, cold and snow; curved igloo shapes present the minimum surface area for the largest volume and use few openings at right angles to the wind direction. At lower latitudes the climate moderates and summer heat as well as rain becomes significant. Thus windows are designed to admit the winter sunshine whilst excluding it in the summer using overhangs or various shading arrangements; insulation is used to minimize heat loss, and ventilation helps to counteract heat gain. Heavy mass buildings with shaded courtyards are common in hot, dry tropical regions which usually have a large diurnal temperature range; advantage is taken of evaporative cooling from pools and even the soothing sound qualities of running water in fountains; sand and dust are further factors requiring consideration. Hot humid tropical areas are most demanding on the human system because evaporation from the body by sweating tires the body; every opportunity has to be taken to allow cross-ventilation currents to flow through the roof space and through preferably high rooms. In Malaysia, timber homes on stilts, with many openings to collect every breeze, are common; this relieves the effects of the high levels of relative humidity.

Iranian (or historically Persian) architecture displays a lot of evidence showing how ingenuity can combine planning, building shape, materials and systems design to produce simple but effective solutions to environmental control problems (beautifully illustrated in edited by George Michell (1978)). Although the control is coarse there is an inherent flexibility which allows the buildings to be in rhythm with the natural cycles of temperature and sunshine. Buildings were closely clustered, partly to aid defence but also to reduce the impact of solar radiation and dust. Tall walls and narrow streets provided shade for pedestrians. Curved roofs were incorporated into buildings as early as 3,000 BC. The curvature accelerates the rate of airflow over the surface so that the consequent decrease in pressure induces any hot air which is stratified on the underside of the roof to flow out through air vents. Thick adobe walls retain the heat and release it to the interior and to the night sky as the cooler evening descends. Landscaping has always played a role in shielding walls from solar heat and courtyards are used to entrap cool night air for several hours.

Air-conditioning is often thought of as having emerged in the nineteenth century, but there are many examples of what one might term air-conditioning in the truest sense of the word in much earlier times in Egypt and India. Wind scoops are prominent features of the Lower Sind District in West Pakistan. The air-conditioners of Hyderabad are in reality the (wind catchers) that channel the wind breezes into each building. They are installed on the roofs, so that temperatures of 50°C which are experienced in summer are lowered by the breeze to what is felt to be a pleasant 35°C.

WIND TOWERS AND WIND CATCHERS

Wind towers (in Arabic called and also ) are often referred to as wind catchers ( means ‘wind’ and means ‘catcher’) or wind scoops, and they harness summer breezes. Examples of wind towers can be found throughout the Middle East, Pakistan, and Afghanistan and now are sometimes incorporated into Western architecture.

They are an ideal example of a natural ventilation system which relies on a combination of features: the mass of the thick adobe walls; flexible openings at the top of the tower; doors and windows in the living spaces; and the wind pressure differentials on each side of the tower.

Wind flowing around a building causes a separation of flows which creates a positive pressure on the windward side and a negative pressure on the leeward side of the building. Due to its height, the wind catcher enhances the positive pressure on the windward side; it is then directed through the tower into the building. Airflow follows the pressure gradients within the structure and exits through purposely designed openings and through the leeward side of the tower. The size and location of openings (e.g., windows, doors, etc.) and distribution of internal party walls have a great impact on encouraging cross flow and mixing of the indoor air.

Fig. 2.2 (a) Wind catcher operation; (b) a wind catcher and used for cooling (Yang Chen, FINC Architects); (c) paintings of chimneys acting like wind towers in Santa Luzia, Portugal (painting: Maxine Relton).

In addition to the pressure-induced flows, the principal factor in wind towers is buoyancy: in the day solar heat absorbed by the walls of the tower warms the air which then rises but at night there are often clear skies and the temperature drops significantly, cooling the tower walls; hence the air inside is cooler, so moves downwards. Doors and windows can be opened to assist any upward air movement on warmer nights; if there is a breeze at night the flow is downwards and the air warms slightly...