2009 Open Architecture Challenge: Green School Classroom 3

Partner School

Green School, Bali-Indonesia
Jl. Raya Sibang Kaja, Br. Saren, Abiansemal
Badung, Bali 80352, Indonesia
Phone: +62 361 469 875
www.greenschool.org

Green School and Sustainability

Located in central Bali, Sibang Kaja, Green School’s campus spans nearly ten hectares on either side of the Ayung River. Green School serves as a model to local and international communities not only in how to educate students about sustainability, but in how profoundly environmental concerns are integrated into our learning, philosophy, and daily lives.

Responsible Building

Every aspect of the site and buildings are living examples of sustainability, the School’s many buildings are cooled and powered by sustainable energy solutions including micro-hydro power, solar power, bio-diesel and predominantly natural air-conditioning.

Indonesian bamboo, local alang-alang grass, traditional mud walls, and mud brick are used to construct classrooms, athletic facilities and other school buildings to minimize the use of non-sustainable materials such as concretes and plastics. The goal is to use between 99 and 100 percent natural materials in all construction projects, to recycle as many materials as possible, and to manage waste responsibly.

Renewable Energy Solutions

Green school strives to be as energy independent as possible. To that end, the school is implementing an experiment in micro-hydro power generation, the nine-meter vortex generator. In addition, the school produces methane from cow manure for fueling stoves, solar panels for electricity, and is developing a gasification unit that will use rice husks and other organic materials to produce electricity.

Sustaining Needs and Appetites

The campus is blanketed by an organic permaculture system designed by international and local experts. The School’s gardens grow rice, fruits, vegetables, palm sugar and cacao, produces coconut oil, harvests honey and breeds fish.

These abundant natural resources provides self sufficient farming and connect students directly with the land forming the basis of the experiential learning component fundamental to Green School curriculum.

Bridging Communities

Linking the Campus from east to west, an elegant Bamboo Bridge is suspended across the Ayung River. In addition to the students and staff who use the bridge to move through campus, hundreds of Balinese cross the bridge to attend temple, travel to their rice fields, and head to work or school.

Thus this beautiful span serves as an apt metaphor for what Green School believes to be true about sustainability: “no program will make a real impact unless it is able to bridge cultures and embrace the weave of communities that surround and are integral to the campus. “

Green Schools commitment to the local community extends to a twenty percent intake of Balinese children who attend Green School through a scholarship program. Additionally the Green School has developed a program for educating local children about waste management and local schools are taking on projects to grow and maintain bamboo. The interaction and sensitivity towards the local and global community further enhances the unique international community focus.

DESIGN PRINCIPALS

Site and Context

Green school classrooms are located on the western ridge of the campus sited around a central ‘edible’ courtyard garden. Student circulation through the courtyard promotes interaction of all year levels whilst plant varieties are named for children learn about botany, biology and cultivation.

Blending traditional Balinese building techniques with contemporary organic building forms the Green School classrooms connect learning with creativity, environmental responsibility with scientific knowledge, and respect for the indigenous Balinese culture surrounding the campus.

By adopting traditional building techniques and materials, the classrooms are not only visually sympathetic to the immediate surrounds but extend to respond climatically to seasonal variation for student comfort through passive means of ventilation and shelter. All materials are sourced in the immediate vicinity of the campus, both minimizing the carbon footprint of transportation and production and supporting local industry.

Spatial Planning

The classroom is designed around 3 interchangeable and flexible spatial conditions; formal, informal and intimate.

The classroom adopts a triangular plan, a large floating roof, open walls and minimal structural columns. The classroom is planned for maximum open space, facilitating flexible spatial arrangements to accommodate different teaching styles. Within the triangular plan are located 3 interchangeable yet distinct spatial conditions;

1. Formal classroom with desks facing teacher and black board
2. Informal meeting space with circular couches ideal for brain storming and creative thinking.
3. Communal desk and work bench for art and group exercises

Adjoining to the main triangular class room is a smaller circular structure. This secondary structure adopts the form of a Mongolian ‘yurt’. The yurt offers a forth spatial condition; a more controlled and focused alternative to the large open plan class room. The yurt is devoid of furniture and windows, the students sit on the ground, around the perimeter wall. Seated on pillows opposite each one an other the yurt facilitates group exercises and peer to peer learning.

All furniture is made entirely of bamboo; light weight and movable for different teaching requirements. School desks interlock in different spatial arrangements, they can also be separated for individual learning or adjoined in pairs and groups. Storage units act as both screening devices and storage, all inherently organic and playful. Additional freestanding units take the form of a pineapple, celebrating the creative and the practical.

Technology

Green school strives to be as energy independent as possible. Experimentation with sustainable renewable energy solutions extends to ; micro-hydro power generation, methane from cow manure for fueling stoves, solar panels and a gasification unit that uses rice husks and other organic materials to produce electricity.

Through the use of skylights and passive ventilation and cooling, energy intensive artificial lighting and climate control systems are virtually redundant. Each student is issued with a laptop computer, powered by renewable energy, further illustrating Green schools commitment to 21st century education beneath an environmental umbrella.

Materials and constructions

All materials incorporated are locally available materials and simple construction techniques that address prevailing climatic conditions.

Petung bamboo, Dendrocalamus asper, is adopted as the primary structure forming 3 interlocking trusses dissecting the triangular plan. The structural loading of the trusses are transferred to foundation though a traditional structural column type known as dupit.

The primary structure is anchored to the foundations by an innovative method of lacing river rocks and bamboo with reinforced steel connected to the concrete foundations. The bamboo connection to ground plane is tapped and filled with cement creating a solid structural connection for wind loading.

The secondary structure and rafter elements are lighter weight Bamboo Tali, Gigantochloa Apus. The rafters are installed at 300 mm centres fixed to the primary bamboo Petung with bamboo pins.

Alang-alang or Balinese grass strip tiles are overlapped and individually tied to form the roofing surface adding additional bracing and strength to the structural components. The a 3 interlocking trusses form breaks in the roof plane which are covered by canvas forming skylights.

The secondary yurt structure is constructed from black bamboo tali in a diagonal lattice forming the circular wall. The walls are covered in canvas allowing diffused light to penetrate the interior The roof structure is again constructed from black bamboo tali linked to a circular glass skylight.

All bamboo is extensively treated using the organic compound Borax. The bamboo is first cleaned and then submerged in a Borax bath for a period of 4-6 weeks ensuring resistance to pests.

Using three dimensional computer modelling and virtual simulation, the structures are engineered by the University in Yogyakarta. The simulation tests wind and structural loading, allowing detailed analysis to be fed back into the working models and drawings ensuring structural integrity and certification of proposed buildings.

The finished floor surface is a cement and mud mix, minimising the use of cement and colouring the floor a desirable earthy tone.

All products incorporated for protective finishing have been audited for sustainable practice with a preference for 100% organic products such as tongue oil replacing toxic polyurethane coatings.

Traditional Balinese construction techniques are fundamental to the structure, yet the form and building geometry has been derived from non-linear geometry. With the exception of 6 key nut and bolts, all fixings and joins are bamboo pins, allowing for organic shift with in the material without cracking.

Lighting, Ventilation and Acoustics

Along the double arched structure of the roof is located a canvas skylight running the length of the building. The open perimeter walls and central skylight allows ample natural and diffused daylight to enter the building, allowing efficient lighting for teaching needs and eliminating the need for artificial lighting during day light hours. Additional low energy lighting is incorporated for after hour needs, powered by renewable energy such as solar panels.

The combination of open walls and semi detached skylight also allows passive cross ventilation and natural upward draft to vent and cool the building. For the hottest days the central ‘bubble’ is fed by a huge fan cooling the students through the peak mid day sun.

The thermal mass of the Alang-alang grass roof protects the students from direct thermal gain as well as acting as sound absorption for acoustic comfort. The black board and storage units act as partitions and screens adding additional acoustic protection from and to adjacent classrooms.

Why Bamboo?

A single bamboo clump can produce up to 15 kilometers of usable pole in its lifetime.
Certain timber bamboos have better tensile strengths that iron or steel on strength per weight ratio.
Over one billion people in the world live in bamboo houses, and the world’s recognized 1,100 to 1,500 species range in geographical distribution from the tropics to temperate climates, from 46 N to 47 S, and in altitudes up to 4,000 meters.
The world trade in bamboo and rattan is currently estimated at US$ 14 billion per year, and bamboo’s commercial consumption is expected to reach US$ 20 billion per year by the 2015.
Bamboo is the most diverse and primitive group of plants in the grass family, and has one of the highest rate of photosynthesis of any plant species in the world.
Bamboo is extremely resilient; in fact a species of bamboo was the first plant to return to life after the atomic bombings of Japan in 1945.
Bamboo can grow at an incredibly rapid rate, up 1.2 meters in 24 hours!
Certain bamboo root clumps can live for hundreds of years, providing a dependable and steady supply of materials; in fact, a mature 100’ by 100’ patch of clumping timber bamboo can produce enough material to produce a house every year!

Did you know?
Bamboo is naturally hypo-allergenic and anti-bacterial, preventing odor, allergies and skin irritations.
Bamboo has for centuries been used in Ayurveda and Chinese acupuncture.
Bamboo has double the absorbency of cotton.
Bamboo is an essential structural material in earthquake architecture.
Bamboo is the most sustainable textile material available on the market.
Bamboo is considered as a mystical plant throughout Asia. It is a symbol of strength, flexibility, tenacity, endurance and compromise.
Due to its high nitrogen consumption, bamboo helps mitigate water pollution, making it a solution for excess nutrient uptake of wastewater from manufacturing,
livestock farming and sewage treatment.

Uses of Bamboo:

Wind protection
Bamboo leaves added to compost create a natural fertilizer
Bamboo added to rice compost creates natural fungi protection
Soil erosion control
Road embankment stabilization
Irrigation pipes
A source of food and fodder
Storage containers
Musical instruments like flutes and xylophones

Overview of Bamboo

The grass – bamboo – is believed to be the fastest-growing plant on the planet. It is considered to be one of our most sustainable resources, and its stands release 35% more oxygen than equivalent stands of trees. Some bamboo even sequester up to 12 tons of carbon dioxide from the air per hectare. Bamboo can also lower light intensity and protects against the sun’s harmful radiation. Bamboo can be harvested in as little as three years up to five years. It is also incredibly strong having been tested and proven stronger in comparison to steel on tensile strength per weight ratio. Certain varieties can grow to over 60 feet in several cases without the aid of toxic pesticides and fertilizers. When treated, bamboo forms a very hard wood which is both lightweight and exceptionally durable. In tropical climates it is used in elements of house construction, construction scaffolding, as a substitute for steel reinforcing rods in concrete construction.
Bamboo flooring is widely available, some of which is comprised of 100% bamboo, planed and pinned together with bamboo pins, using no glue, or chemical finishes as in most comparable flooring laminates. Furthermore, bamboo is an ecological construction material that is earthquake and cyclone resistant, and has also seen international certification for the resistance qualities, with three ISO standards currently available for bamboo as construction material. Alone, a peerless erosion control agent, it's net like root system create an effective mechanism for watershed protection, stitching the soil together along fragile riverbanks, deforested areas, and in places prone to earthquakes and mudslides. In short, bamboo is resilient, super strong, and sustainable and an exquisite component of landscape aesthetics.

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