Chilean Eco-Buildings Pioneering Construction Methods

By David South, Development Challenges, South-South Solutions

SOUTH-SOUTH CASE STUDY

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.

Resources

1) Series of photographs and architectural renderings of the Transoceanica headquarters. Website: http://www.plataformaarquitectura.cl/2010/10/28/edificio-transoceanica-arquitectos-2/

2) World Hands Project: An NGO specialising in simple building techniques for the poor. Website: www.worldhandsproject.org

3)  Builders Without Borders: Is an international network of ecological builders who advocate the use of straw, earth and other local, affordable materials in construction. Website: http://builderswithoutborders.org/

4) An inspiring collection of prefabrication buildings and the techniques used to make them. Website: http://inhabitat.com/architecture/prefab-housing/

5)  Tiny House Design Blog: The blog is full of ideas and plans for making small homes cheaply. Website: http://www.tinyhousedesign.com/

6)  Building and Social Housing Foundation: The Building and Social Housing Foundation (BSHF) is an independent research organisation that promotes sustainable development and innovation in housing through collaborative research and knowledge transfer. Website: http://www.bshf.org/

Creative Commons License

This work is licensed under a
Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License.

Leave a Reply

Please log in using one of these methods to post your comment:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

w

Connecting to %s