Although there is no overall consensus on what constitutes green architecture, we can say that most experts agree that it is a form of construction that respects the environment and looks to use natural resources in a sustainable way.
Chicago City Hall, USA
In 2001, the rooftop of Chicago City Hall was transformed into a garden allowing temperature control and maintenance, improved water resistance and reduced energy costs. Its 6,187 m2 of plants and vegetation are designed to simply improve the building and visits to the garden are not permitted. It is calculated that the garden helps save US$5,000 a year in energy costs, in addition to improving air quality and rainwater catchment. Many other buildings in the city have followed the city hall’s example since the scheme was launched.
California Academy of Sciences, USA
The complex that houses the California Academy of Sciences is not only an extravagant display of technology, art and entertainment, but its buildings are designed to blend in with nature and maximise their surroundings. The most interesting aspect is its green roof that uses earth and plants as insulation, while at the same time 60,000 solar panels produce 10% of the energy it needs to function. Rainwater catchment and its large windows allow the building to make the best use of light and also improve air quality.
Earth Houses, Switzerland
Architect Peter Vetsch is the man behind one of the most famous green constructions. These nine houses are located on a 4,000 m2 site in Dietikon, Switzerland. Their construction has minimal visual impact as they are designed to blend in with the landscape. The earth and vegetation covered rooftops mean it is easier and more cost efficient to regulate temperature. The sturdiness of the structures mean that the building materials last longer and dust and other allergy causing particles are kept away from the tenants.
Frankfurt International Airport, Germany
One of the most famous green buildings in Germany is Frankfurt International Airport. Green roofs have been developed on many of the airport’s buildings, providing a total of 40,000 m2 of vegetation. Similar to the buildings already mentioned, the roof allows temperature to be regulated, air quality to be improved and use to be made of rainwater. Its aerodrome is the one that occupies less space in the world in respect to the amount of air traffic that passes through. Other green aspects include efficient use of water in its toilets and use of natural light. In total, such features make this airport the greenest in Europe.
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Salt Lake City Convention Centre, USA
The auditorium belongs to The Church of Jesus Christ of Latter-day Saints. Although it's not eye-catching building, it has ample vegetation on its roof and its construction blends in with its surroundings. It is considered as one of the largest religious buildings ever built. Its waterfall, terraces, gardens and walkways add to a total site size of about 304,000 m2.
Imperial Hotel, Tokyo, Japan
This was originally the site of a work by important American architect Frank Lloyd Wright but the building was demolished in 1968 to make way for an imposing and modern five-star hotel. The current building has a rooftop garden that helps minimise climate effects within the hotel and a series solar panels to help illuminate the building. It is not the greenest building in the world, but the fame of its lake and the design of its roof make it a reference point for architects.
School of Art, Design and Media, Nanyang, Singapore
This impressive building is part of a larger complex situated in Singapore. Its design really stands out and its use of natural light and gardens make it one of the greenest buildings in the world. The vegetation on its roof helps maintain a pleasant temperature inside the building and helps collect rainwater to water other areas of the campus. The School of Art, Design and Media also allows students and professors to hold meetings in spaces dedicated to contact with nature.
Thermal spa-hotel, Bad Blumau, Austria
A perfect blend of art, architecture, painting and ecology, this building is the work of one of the most versatile artists the world has ever seen. Designed by Friedensreich Hundertwasser, construction of this spa-hotel began in 1993 and was completed four years later. He succeeded in not only creating an imposing and striking structure based within art but also one the buildings most attuned to nature. Its system of roofs, terraces and walkways together with its use of the elements make this an excellent example of green architecture. Hunderwasser’s obsession with nature even led him to embed trees and plants in the rooms, as if they were other guests and not just for decoration.
Art and Exhibition Hall, Bonn, Germany
With its garden of 8,000 m2 located on the roof, this construction in Bonn is one of the greenest in Europe. In contrast to the majority of the buildings we have already seen in this list, the main use of this garden is as a space in which to exhibit sculptures. Nevertheless, the impact of the vegetation on air quality and temperature control is a benefit that helps place this building in our ranking.
ACROS building, Fukuoka, Japan
The vegetation-covered terraces on one side of this 15-floor building make it stand out among neighbouring buildings as its design means much of its steel and concrete is covered. Built by Emilio Ambasz in 1995, the building is one of the few green areas in the city of Fukuoka. If the terraces are added to the adjacent park, then this complex adds up to 100,000 m2 of green space. Like other buildings in this list, the ACROS utilises efficient and responsible use of light and water to create a natural environment inside.