arch 213ecological issues in architecture

learning from vernacular architecture

La maison des Hommes by Le Corbusier

The techniques of passive solar building design were practiced for thousands of years, by necessity, before the advent of mechanical heating and cooling. It has remained a traditional part of vernacular architecture in many countries.

There is evidence that ancient cultures considered factors such as solar orientation, thermal mass and ventilation in the construction of residential dwellings.

Fully developed solar architecture and urban planning methods were first employed by the Greeks and Chinese who oriented their buildings toward the south to provide light and warmth.

Socrates, the Greek father of philosophy known for his interest in questioning, was also a careful observer of the sun’s movements.

The most often cited example of awareness of passive solar use is a concept house, the "Megaron House “ described by Socrates (469-397 B.C.). He expressed the following thoughts: "Doesn't the sun shine into houses facing south in winter, whereas in summer the sun wanders over us and the roof so that we have shade?

Because this is comfortable, then south-oriented rooms should be built higher in order not to shut out the sun, whereas the north rooms should be lower because of the cold north wind."

This was the logic for this funnel-shaped house concept, opening in plan and section to the south. A roofed porch admitted sunlight into the main room in winter but shaded it in summer. A room to the north served as both storage and as a buffer from the north exposure.

The ancient Greek playwright Aeschylus, who lived hundred years later than Socrates was even more harsh:“Only primitives & barbarians lack knowledge of houses turned to face the Winter sun.”

The ancient buildings of Greece have both thermal mass as well as southern facing orientations.

The Anasazi Native Americans built their homes in the side of the cliffs.These south-facing buildings were placed within the side of the cliff to avoid the sun in the summer, but make use of the sun during the winter.

This photo was taken in the Fall, on Sept. 12th, when the sun is no longer high in the sky.

Vernacular architecture in history, built by Egyptians, Greeks, Persians, Hindus, the Native Americans and many more nations considered the climate and locally available materials.

In the past, the architecture was utilized to make optimum exploitation of the sun and wind to lessen the extremes of the climate, but due to a lack of glass, they were unable to utilize the sun to the extent we can today.

Although most ancient civilizations lacked glass and other technology that we use today, they still made significant progress and provided understanding and a good foundation for future developments regarding the use of the sun and wind.

Wind towers of the Middle East for example -built in 10th century- utilized the power of the wind to provide ventilation in the hot and arid climate of the desert.

Wind towers to catch the breezes..

The function of this tower is to catch cooler breeze that prevail at a higher level above the ground and to direct it into the interior of the buildings. Wind catchers come in various designs, such as the uni-directional, bi-directional, and multi-directional. Examples of wind catchers can be found in traditional Persian influenced architecture throughout the Middle East , Pakistan and Afghanistan.

Central Iran has a very large day-night temperature difference, ranging from cool to extremely hot, and the air tends to be very dry all day long. Most buildings are constructed of very thick thermal mass with extremely high insulation values. Furthermore, towns centered on desert lands tend to be packed very closely together with high walls and ceilings relative to Western architecture, maximizing shade at ground level. The heat of direct sunlight is minimized with small windows that do not face the sun.

Wind towers to catch the breezes..

From above: mono-directional wind tower ; multidirectional wind scoop; combined wind tower.

Yazd, a city of wind towers or "badgirs" (wind catchers) lies quietly in the middle of a desert. The wind towers of Yazd are built with thick walls and tall arches

The famous Dowlat-abad windcatcher in Yazd, Iran

The burj al hawwaThe burj al hawwa, or wind tower was designed for use in dense urban situations where there was a need to draw air down into the compact, courtyard houses. Without the construction of such tall towers there would be no possibility to take advantage of the prevailing winds and breezes either from the shamal or from the on- and off-shore breezes associated with developments located by the sea.

In Qatar, as in the rest of the Gulf, the wind towers were constructed on a square plan and contained a cruciform device on the internal diagonals which allowed air to funnel down into a space at the bottom of the tower. This took place both through the direct impact of breezes striking the exposed face of the diagonals, as well as through the principle of convection on the other three faces when the structure was warmed by the sun and ambient air.

The burj al hawwa

A wind tower at the Madinat Jumeirah

Before the invention of air conditioners, inhabitants of the Middle East used wind towers to capture wind and cool their homes. This is a wind tower at the Madinat Jumeirah. The wooden cross bars were draped with wet cloths so the wind would cool as it blew into the homes in an early evaporative cooling scheme.

Wind towers in the Bastakiyya Quarter Heritage site in Bur Dubai

Wind towers atop Borujerdi ha House, built 1857, in Iran

The Global Ecology Center in Stanford, California, USA,

RARE Headquarters, Twycross, Leicestershire, UK

Wind towers at Headquarters of Ionica, Cambridge, UK

Wind scoops at Bluewater Shopping Centre, Kent, UK

Qatar University in Doha

Qatar University in Doha

Beginning in the 17th century, interest grew in regards to using the sun as an energy source, and though there was not a large amount of development within passive solar techniques, significant progress was made in active solar systems.

It was in the late 19th century that passive solar energy began appearing more often and in more noteworthy means. In 1880, theories surrounding solar houses began to appear, and it was in Salem, Massachusetts that the idea of a glazed, south-facing wall, as well as incorporating the requirements for air flow between the glazing and the wall first arose.

Not only that, but professor E.L. Morse was approved for a patent “for the combination of a dark colored massive wall, an air space, glazing…and adjustable dampers by which the flow of air could be controlled”.

A few years later, in 1896, the thermosyphon water heater was invented, the oldest and most widely used passive solar device in the world, which was utilized in World War I in Southern California to provide hot water to army camps.

Based on the work of Edward Morse in the 1880s, Frenchman Felix Trombe in 1960 developed a system where a glazed wall facing the sun absorbs the sun’s heat and releases it inside the building at night. The picture shows a modified Trombe wall that utilizes a glazing material to collect solar heat and vents to provide air flow and distribute the heat to the interior room.

Although earlier experimental solar houses were constructed using a mixture of active and passive solar techniques, some of the first European engineered passive solar houses of the modern era were built in Germany after World War I, when the Allies occupied the Ruhr area, including most of Germany's coal mines. Architect George F. Keck was a pioneering designer of passive solar houses in the 1930s and 40s.

He designed the all-glass ‘Crystal House’ and ‘House of Tommorrow’ for the 1933 Century of Progress Exposition. Following this he gradually started incorporating more south-facing windows into his designs for other clients, and in 1940 designed a passive solar home for real estate developer Howard Sloan in Glenview, Illinois.

CRYSTAL HOUSE

HOUSE FOR TOMORROW

The Sloan House was called a "solar house"by the Chicago Tribune, the first modern use of that term. Sloan then built a number of passive solar houses, and his efforts contributed to a significant "solar house" movement in the 1940s. In the United States as well as Europe, interest in passive solar building design was significantly stimulated by the 1973 oil crisis.

Sloan house