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Jun242015

Chilean Eco-Buildings Pioneering Construction Methods

Wednesday, June 24, 2015 at 11:59AM

Across the global South, the search is on for new ways to build without extracting a high price from local environments.

More and more people are recognizing the advantages of energy-saving methods like prefabrication. Prefab building techniques involve assembling a structure from pre-assembled parts or modules made in a factory, or transporting a completed, factory-made structure to a site (http://en.wikipedia.org/wiki/Prefabricated_building). Pre-fabrication has many advantages, especially now that information technologies bring precision to the building process. Prefabrication means the construction process can be tightly controlled, helping to avoid waste, time delays, weather problems, or any of the other idiosyncrasies of a building site. It can also allow large numbers of dwellings to be built quickly by maximizing skills and efficiencies in an assembly-line model of production.

In South America, a Chilean architecture company has pioneered innovative methods to build and deploy accommodation for tourists in an ecologically fragile area. The prefabricated wood cabins also use many emerging saving technologies and clever design tweaks to protect privacy when located close together.

Easter Island (Rapa Nui) (http://en.wikipedia.org/wiki/Easter_Island) sits 3,500 kilometers off the Chilean coast and is well known for its iconic, giant head ancient stone statues, or moai (http://en.wikipedia.org/wiki/Moai). Around 3,791 people live on the island – one of the most isolated inhabited islands in the world – which is both a UNESCO World Heritage Site and a popular tourist destination.

Tourism is vital to the local economy and many people make their living from it. Enterprises making money from tourists range from dive shops and craft stores to restaurants and hotels.

The island has had a good connection between tourism and improvements in living conditions, with tangible improvements made since the increase in tourism in the 1960s. Clean water and electricity were provided and a hospital and a school built.

In the past few years, more flights from Peru and Chile have increased opportunities to visit the island and lowered flight times. The island’s only airport is being expanded to further increase the capacity of flights, a project due to be completed by 2015.

But tourist numbers in 2010 declined from 2009 and this has been attributed to ongoing conflicts between Chilean authorities and the indigenous Rapa Nui people over ancestral lands.

Here as elsewhere, the challenge is to balance tourism with the fragile local environment. Any further expansion of tourism will need to sit lightly on the land and respect the rights of the Rapa Nui people.

The brief for the Morerava eco cabins (http://www.morerava.com/) was to provide environmentally sensitive accommodation that uses few local resources. Built by Santiago-based Chilean architects AATA Associate Architects (http://aata.cl/), the cabins were prefabricated in a factory and shipped to the island during 2010.

The architects specialize in industrial, commercial, educational and institutional, residential and interior design. They pay attention to environmental conditions and the use of resources.

The cabins are arranged around an elliptical courtyard reflecting the shape of the island’s flag design. They have an open-plan set-up and are long and skinny, with rooms arranged in a line from end to end. Nine cabins accommodate six people each. Cleverly, they are designed to retain privacy while being close together. Privacy is maintained through a strategic use of window placement. On one side of the cabin, the windows are high, while they are low at foot level on the opposite side. This prevents there being a direct sight line into the next cabin, while allowing plenty of light to stream in.

Having the cabins built on the Chilean mainland avoided using up local vegetation and resources. Easter Island once was covered with a palm forest. But over the centuries of human habitation, the forests were cut down and the island became almost barren.

Propped up on stilts, the cabins hover over the moist grass floor to avoid damage from rot. The roof is sturdy and made from zinc steel.

They use little water and energy to function. Cross-ventilation airs the cabins and avoids mechanical systems like energy-gobbling air conditioners. Electricity on the island is generated from expensive petrol, so any means to avoid using it means a big savings.

With a mild climate, the cabins do not need insulation.

Water is captured from rainfall on the roof and is then drained into a storage tank below the cabins (http://en.wikipedia.org/wiki/Rainwater_harvesting), and hot water is provided by solar heaters placed on the rooftops. This system circulates the hot water without electricity by using a technology called thermosiphon (http://en.wikipedia.org/wiki/Thermosiphon) which exploits the natural phenomenon of heated water being less dense and rising while cooler water flows downward through the force of gravity.

At the other end of the construction spectrum, one of the most notoriously energy-wasting of structures – an office building – has been given a green makeover. Another Chilean pioneer in green architecture is the Santiago headquarters of Empresas Transoceanica (http://www.transoceanica.cl/), a private investment company in real estate, hotels and tourism, agro-industry and logistics. Its new campus HQ – part park, part office building – maximizes light through the building’s long and bulbous shape.

Designed to reduce energy demand while improving work spaces, it favours natural light while avoiding excess heat build up through wooden slats outside the building.

Geothermal energy comes from a well 75 metres below ground. This provides water cooled at 12 degrees Celsius, to cool the building. The building has been built following the strict environmental guidelines laid down in the LEED guidelines (Leadership in Energy & Environmental Design (LEED) – an internationally recognized green building certification system (http://en.wikipedia.org/wiki/Leadership_in_Energy_and_Environmental_Design).

Extensive planning and design work went into making sure the building’s structure, orientation, lighting, insulation and landscaping reduced energy use and need for energy-intensive mechanical solutions. Skylights bring natural light into the building’s public spaces. There are three stories above ground and two stories below providing underground parking.

The landscaped park around the building is actually the roof for the underground parking garage. The whole edifice creates a seamless connection between the building and the greenery and water features surrounding it.

By David South, Development Challenges, South-South Solutions

Published: February 2011

Development Challenges, South-South Solutions was launched as an e-newsletter in 2006 by UNDP's South-South Cooperation Unit (now the United Nations Office for South-South Cooperation) based in New York, USA. It led on profiling the rise of the global South as an economic powerhouse and was one of the first regular publications to champion the global South's innovators, entrepreneurs, and pioneers. It tracked the key trends that are now so profoundly reshaping how development is seen and done. This includes the rapid take-up of mobile phones and information technology in the global South (as profiled in the first issue of magazine Southern Innovator), the move to becoming a majority urban world, a growing global innovator culture, and the plethora of solutions being developed in the global South to tackle its problems and improve living conditions and boost human development. The success of the e-newsletter led to the launch of the magazine Southern Innovator.

Cited in Chile in Transition: Prospects and Challenges for Latin America's Forerunner of Development by Roland Benedikter and Katja Siepmann (Springer, 2015)

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Southern Innovator Issue 1: https://books.google.co.uk/books?id=Q1O54YSE2BgC&dq=southern+innovator&source=gbs_navlinks_s

Southern Innovator Issue 2: https://books.google.co.uk/books?id=Ty0N969dcssC&dq=southern+innovator&source=gbs_navlinks_s

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Southern Innovator Issue 5: https://books.google.co.uk/books?id=6ILdAgAAQBAJ&dq=southern+innovator&source=gbs_navlinks_s

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Making Bamboo Houses Easier to Build

Friday, June 19, 2015 at 8:43AM

More than 1 billion people around the world lack decent shelter. Of these, the majority live in urban areas, usually in slums and informal settlements (UN-HABITAT). Latin America has a serious shortage of adequate housing: in Colombia, 43 percent of the population needs decent housing; in Brazil, 45 percent; Peru, 53 percent.

The challenge is to provide good quality homes without significantly harming the environment – and with constrained budgets. Bamboo – cheap, strong, quickly renewable and beautiful to look at (http://en.wikipedia.org/wiki/Bamboo) – is an ideal solution to replace traditional wood lumber. In Bolivia, pioneering work is underway to improve the quality of homes and buildings made with bamboo.

Bamboo is the fastest growing woody plant in the world, sometimes growing over 1 metre a day. Bolivia (http://en.wikipedia.org/wiki/Bolivia) has about 17 identified bamboo species, of which five have a significant economic value. Around the world, there are 1,000 species of bamboo. They grow in a wide variety of climates, from cold mountains to hot tropical regions.

Once called the “poor man’s timber” – a temporary building material to replace once there is more money – bamboo is now getting the respect it deserves. Bamboo for housing has a long history in Latin America, stretching back 4,500 years to ancient civilizations. In Asia, it has long been a traditional construction material. But most of the existing bamboo dwellings in Latin America are 50 to 100 years old.

The most popular species of bamboo used in South America is Guadua, which is known for being large, straight and attractive.

“In Bolivia, there is no other building material more competitive in costs,” said Jose Luis Reque Campero, coordinator of the Bolbambu Programme of the Architectural Research Institute, Universidad Mayor de San Simon, Bolivia (http://www.umss.edu.bo/).

“Bamboo is the material that requires less energy, followed by wood and concrete, with steel in last place, needing energy necessary for its production 50 times greater than that required by bamboo.”

Campero also says bamboo is much less expensive than traditional building materials.

“But the biggest advantage is certainly the possibility of planting bamboo, and then reaping houses,” he said.

Campero has focused his efforts on a key component of bamboo housing: the joints that bind the bamboo poles together. Driven by the desire to find ways to improve the ease of building bamboo homes and their strength, Campero came up with the Bamboo Bolivia Space Structures, Structural System: EVO (BBSS-EVO) (named after Bolivia’s president, Evo Morales – http://en.wikipedia.org/wiki/Evo_Morales).

Traditional joints took a long time to make and required power tools and complex instruction manuals. Simplifying the building techniques necessary for bamboo construction was important because, while bamboo was cheap, the labour costs were high.

The joint looks like a giant two-headed Q-Tip. Each end is made of four pieces of bamboo, connected by a long screw with bolts on each end taken from old cars. The joint is inserted inside the bamboo poles and snaps shut, joining poles tightly together and, as each piece is assembled, looking like a child’s building toy as the structure of the bamboo home takes shape.

The new joint was easier to assemble and was quickly adopted by local builders. It also allows for a vast range of structures and shapes to be built, limited only by imagination and physics.

Devising joints made from bamboo has the advantage of avoiding the weight and cost of bringing in concrete, especially to remote areas.

“The manufacturing process is fully in the workshop and indoors,” said Campero, “which in addition to allowing a degree of quality control in production, improves working conditions for staff and protects the material.”

The whole building process adheres to “the principles of the famous phrase: ‘do-it-yourself’.”

The Evo joint allows for flexibility and easy assembly and disassembly, enabling the builder to move around parts of the structure and not be wedded to the original structural plan. This has the advantage of customizing the building to its physical location.

Working in the tropical forests of Cochabamba (http://en.wikipedia.org/wiki/Cochabamba), Campero has been testing his designs with the local people, who were looking to improve the tourist infrastructure in the resort town of Cristal Mayu.

Costa Rica in Central America – ironically a country without indigenous bamboo plants – has used its National Bamboo Project of Costa Rica (http://www.unesco.org/most/centram1.htm) to prove it is possible to both cultivate bamboo and use it to provide housing for the poor, confirming the wisdom of millions of people: bamboo is economical, convenient, safe and looks great.

Campero has received a great deal of interest in his innovations and is looking for funding partners in 2009 to take his work further.

He has this advice for other builders and designers: “Stick to developing local technologies, use what you have and innovate, use native materials and the local environment for the development of elements, components and construction systems. Don’t rely on advanced technology tools for manufacture, and stay in harmony with the human need for creativity.”