The U.S.A. PavilionSergio Palleroni describes the construction of an innovative building in the International Zone
The U.S. Pavilion sits amid a dry plain in an undeveloped quadrant of Auroville, in the International Zone
After years of working in marginalized, informal communities in Mexico, an international community in the southern Indian state of Tamil Nadu presented a dramatic change of venue for the Global Community Service program. Auroville is still largely rural, and rather than developing within a frame work of infrastructure, seems to grow in small unrelated parcels when specific funding is granted. The Mother’s vision included a section of the city that would become the international district, providing housing and meeting space for visitors from around the world. In 2001, several donors gave money for the construction of a U.S. pavilion. A previous delegation of students, from the University of Washington Comparative History of Ideas program, heard about the project and put Auroville representatives in touch with Design/Build Mexico.
The decision to accept this project for the 2002 design/build studio was not easy. For years, we had been working in impoverished communities, where our contributions fulfilled serious needs. Auroville is a well-funded community surrounded by people in serious need, and the well-funded portion would be the client for this project. On the other hand, the site, like most of Auroville, was completely without infrastructure, and this building would challenge our students to provide energy, water, and waste solutions that would test the design/build program’s commitment to environmental sustainability. In the end, the opportunity to contribute an alternative model of infrastructure development that would serve to address Auroville, rural India, and many of the communities we serve worldwide by developing a building which was totally off the grid was too much of an educational opportunity for us to pass by. There was also the opportunity to learn from Auroville’s and Southern India’s strong legacy in use of traditional sustainable materials.
In Mexico, students had been able to design a building during a two-week-long interchange with the clients held when we first arrived. As soon as they finished designing, we would break ground. Working in informal settlements, we avoided any formal design review or official supervision. In Auroville, we had to submit plans for approval well in advance of construction, and this meant scheduling our design sessions for the summer preceding the program. The thirty-seven students met without ever having seen the site to design a building for a culture they couldn’t possibly understand. The intellectual and practical challenges were immense.
In September of 2001, a delegation of three faculty members travelled to India to present the students’ design to the Auroville review panel and to research practical construction matters. The resources available for construction looked good, but the building plans didn’t. The panel of Aurovilians overseeing the project felt that the building didn’t express the identity of Auroville. After some quick design development by the faculty delegation, the panel provisionally approved the building. This bought us the time we needed to redesign on-site, in the manner of our Mexico studio, when we arrived in India with the students.
The site struck us initially as large, flat, and dry: this was by far the emptiest site we’d ever been given. The first challenge for the students was to design a building that would anchor itself in the landscape and culture of Auroville so we wouldn’t end up with a figural mass floating in an empty field. The students used the metaphor of an Indian banyan tree as the dominant building concept. Trees in general have immense symbolic importance in Auroville, thanks to the years of reforestatation work, and because the city is planned around a giant banyan tree, this species was considered spiritually important by the Mother.
The dorm rooms find protection under the canopy of the super-roof
The design called for a series of four small dorm rooms set beneath a giant, separate super-roof, to create the same quality of an “outdoor room” that a banyan tree provides in this climate. The design has the usual east-west linear orientation, presenting its broad front to the soft sunlight from the north. The super-roof shades out most of the hot Indian sun, allowing penetration only at dusk and dawn. The dorm rooms are built of heavy, earthy materials: mud bricks and rammed earth. The super-roof is built of light-weight steel and wood. In this way, the dorms seem to rise from the ground like a trunk, while the massive roof seems to hover lightly above, like branches and foliage. Each dorm room has a roof of its own, constructed of ferro-cement in the shape of a hyperbolic parabola. These four smaller roof forms seem to rest gently on the chunky building walls, suggesting leaves falling from a tree.
Every decision made in the siting and design of the building was meant to lessen the building’s load on both the fragile natural environment and the limited infrastructure of this country. The first intention was to mitigate the intensity of the Southern Indian climate, which is known for its periods of oppressive heat and torrential rains. Compressed earth blocks (commonly called mud bricks) and rammed earth create thick wall sections that absorb heat in the dry climate and keep interiors cool. They also use a minimal amount of cement compared to normal bricks or concrete, maximizing the use of the cheapest and most abundant material around: dirt. While they perform well in heat, they should not be used in situations where they are exposed to intense rain, so the super-roof is instrumental in protecting the walls from monsoon rains. Furthermore, the size and height of the super-roof allows prevailing winds to pass through the larger building complex. The clerestories created by the four smaller parabolic roofs then bring these breezes into each dorm room.
Mimicking a south-Indian banyan tree, the super roof creates shady verandas on either side of the dorm rooms.
The students realized early in the design process that the super-roof was a great opportunity to capture both solar power and rainwater. Several local Aurovilians donated a collection of solar arrays, and a group of students created an energy system that keeps the building entirely off the local grid. They not only planned how they were going to provide solar power, but also selected all low-energy fixtures and fans for the building, to limit the energy demands at the source. Meanwhile, another group of students designed a cistern and water tower to capture, store, and distribute all the rain-water collected from the roof during monsoon season.
Pipes ventilate the building’s six composting toilets
The building’s waste was another concern. Normally buildings in Auroville use standard septic tanks, but many are improperly maintained and leak dangerous waste into the groundwater table. Our students, under the direction of Professor of Forest Resources, Charles Henry, came up with a unique solution to this dilemma. They noted that black water, which includes solid waste from toilets, and grey water, which includes urine and wastewater from sinks, laundry, and showers need very different degrees of treatment, yet in a septic system they are treated together. Black water is highly toxic but requires much less treatment. Students divided the building’s waste stream into two categories: black water and grey water. The black water is treated by using a composting toilet system, where waste sits in composting bins for six months as it dissolves into compost. Grey water is treated by a reed bed and planted infiltration trenches that form part of the building’s landscape plan.
This divided system means that the streams have to be separated at the source, so, while there are showers in each dorm room, all toilets are in a large bathroom at the west end of the building. Certain toilets are designated for solid waste, and others for liquid. The solid waste toilets, or composting toilets, were designed entirely by our students using available local materials such as water bins and car jacks. These toilets pass the solid material to a cabinet beneath the bathrooms that is accessible from the lower, west end of the site. Here, the waste sits in modified water bins and becomes garden compost in six months. Meanwhile, the toilets for liquid waste divert urine to the building’s wastewater stream (coming from showers and sinks) and this is passed into the gray water system. The grey water treatment process begins in a settling tank, where any leftover suspended solids settle out. The remaining grey water passes into a reed bed, where a mixture of gravel and plants naturally filter out the pollutants. The nearly clean water then passes into the infiltration trenches, which are essentially long planting beds. These trenches are planted with banana trees, which have a high tolerance for poor water quality and are able to take up the nearly clean water, thereby keeping it out of the groundwater but in the natural life-cycle.
During the construction of the U.S. Pavilion, students worked side by side with twenty to forty Indian labourers. The Indians often seemed amused or perplexed by the great lengths to which the students would go to find alternative solutions to construction and infrastructure challenges; using rammed earth proved to be much slower and more difficult than we ever imagined, the bathrooms had to be built entirely from scratch, and the super-roof was a major engineering struggle.
Accentuating the problems was the language barrier: few Indians in the site area spoke English. For communication we relied on a job captain whose construction skills were superb, but who often misunderstood us and, in a very South-Indian way, was too polite to let us know he didn’t understand. In the end, however, the students created a building that is remarkably self-sufficient and sustainable. As long as the rains come and the sun shines, the building can produce all the energy and water sixteen guests would need, clean their waste, and keep them cool and dry. In addition, the GCS faculty considers it one of our most architecturally-rich projects to date. As the project neared completion, it was clear that the Indian workers’ amusement had turned to curiosity and admiration. We hope to see some of the low-tech solutions employed in the U.S. Pavilion in use in the local village when we return some day to Auroville.
This is an edited version of an article that was first published in the book “Studio at Large: Architecture in Service of Global Communities”
The USA Pavilion starts off