The house that withstood a storm
How did a foundation-less, two-storeyed mud-and-bamboo construction withstand the devastating impact of Cyclone Thane when all of Auroville reeled under it?
JANAKI LENIN
The trees lay prostrate on the roadside. They dwarfed the men swarming over them, hacking with pathetic little machetes. In the distance, a chorus of chain saws whined like giant mosquitoes. Some trees stood resolutely but crippled, a main limb ripped out. Hidden among the fallen foliage were the electric poles, snapped in half, and the thick, ropelike metal cables that once sizzled with the mad energy of electricity, dangled impotently. Some hung low over the road as I gingerly drove under them, wondering if they would zap the car’s radio antenna.
The once traditionally tile-roofed buildings were left with only a skeletal framework of rafters. The tiles had disappeared when the strong winds blew in from the bay. Trees leaned dangerously on some buildings. Auroville, the international township on the periphery of Pondicherry, had taken a beating from Cyclone Thane. Paul Blanchflower, director of the Auroville Botanical Gardens, bent his elbow and slammed his arm forward and drew it back, “All the trees shook like this and that. The sound was deafening.”
The entire power distribution system had been destroyed. To restore it would take at least two weeks in some areas. The backwoods would have to wait as long as a month, if not longer. For a couple of days after the cyclone, it was impossible to reach anyone as their cellphones had lost power and land lines were down. Eventually, the Auroville Town Hall created a charging centre where residents could power up their phones.
No power meant no water. Generators were in greater demand than they were in supply. Life stood still while people stayed home anticipating the arrival of the rental generator. Where water was available, people stood in long, snaking queues to get a few litres.
Amid this chaos, a few communities were quicker to bounce back to normalcy. On the evening of December 29, most of Auroville plunged into darkness when the grid power went off. However, Nina Sengupta, a forest ecologist, and Alok Mallick, an alternate technology expert, followed the cyclone’s course on television even as Thane grew with menacing intensity outside their home. They had opted for renewable energy and were not dependent on the electric poles being snapped like matchsticks by the cyclone.
During the early hours of December 30, when the hurricane was at its worst, the wind wrenched a couple of solar panels from their roof and smashed them into the surrounding woods. The batteries charged from the preceding days’ sunny skies lit up the house until the torrential rains stopped two days later. When the sun came out, the remaining panels began producing enough energy and Nina was able to narrate their ordeal on Facebook. They and their dogs had holed up in a room farthest from a tree they feared would crash-land on the house.
As I walked down the chain saw-cleared pathway, through piles of broken branches and fallen trees, I came upon the broken solar panels that Alok had salvaged from the woods. They were damaged beyond repair. The sight of their house puzzled me. It looked like an ordinary concrete house. But I knew it was not.
Four years ago, when Nina and Alok decided to build a house, they committed to building an ecologically sensitive house. They felt digging into the earth for the foundation was not only unnecessary and expensive but also consumed a lot of energy. They didn’t want to build with bricks (the kilns are fired by wood and therefore carbon-guzzling). Instead, they sourced building materials from a 50 km radius.
Instead of reinforced pillars and beams, a grid work of locally grown bamboo supports the house. The outer walls are made of a mixture of mud and coconut coir. The coconut fibre takes the tensile load and prevents the mud from cracking when it dries. It’s the same concept as fiberglass, explained Alok. Additionally, the 40 cm thick mud walls insulate the house from the weather, keeping it cool during summer and warm in winter. Concerned about termites, they opted to use concrete for the floor, ceiling and plastering. If they had to build the house again, Alok said with conviction, they wouldn’t use concrete at all.
How did a foundation-less, two-storey mud and bamboo house withstand the cyclone, I asked incredulously. “It’s still standing,” replied Alok. At the four corners, granite posts anchor the building to the ground. Although trees with far deeper roots were being uprooted and tossed around by the malevolent-spirited Thane, the house with no foundation did not budge. As long as the building is well-balanced, a foundation is unnecessary, Alok believed. Just as a ship floats on water, the house floats on earth, he added. It’s built to be flexible during an earthquake and yet unshakeable when a cyclone rages.
Although mud is local, digging it up does impact the earth. So the indoor walls are made of bricks of fly ash, an imaginative way of re-using a waste product. It took only four months to build the house. Nina said they hired unskilled labour who were so intrigued by the use of bamboo and mud that they seldom played truant. They were eager to see the mud house take shape in front of their eyes.
The house is entirely run by renewable energy. During the day, the solar panels charge a bank of batteries to power the house at night. Even on rainy days, the panels generate electricity from mild radiation, and there is always enough energy to get by.
Clusters of LEDs illuminate the house at night, fans stir the still air, and when the weather gets muggy, a dehumidifier keeps one room dry. The solar panels also power a 300 litre refrigerator, Alok’s ham radio station, satellite television, and computers. “What have you skimped on to live on alternate energy?” I asked. “Nothing,” they chorused. They even run a water pump and washing machine on solar power. Having a low carbon footprint and producing power isn’t all there is to this novel enterprise. They even harvest their water.
The flat roof acts as a rainwater collector, and the water is directed to an artificial 130,000 litre, high-density polyurethanelined aquifer. This is filled with sand so soil microbes maintain water purity. When needed, the water is pumped to an overhead tank by a solar pump. However, the aquifer is only partly completed and until it is fully commissioned, the couple is dependent on borewell water pumped up by a windmill.
“Surely these tall structures aren’t cyclone-proof,” I argued, pointing to pictures of damaged and broken windmills on the Auroville website. A locking mechanism stops the blades from turning during high winds, explained Alok. But people get annoyed when the safety device triggers frequently. They disable the lock, which is critical when cyclonic winds reach speeds up to 130 kmph.
All waste water at Alok and Nina’s place is routed through a treatment system and the treated water is used for gardening. A part of the roof held a green house where Nina grew vegetables and herbs until the cyclone knocked it down.
“Functioning with an alternate system does call for two adjustments,” says Nina. One is calculating the wattage consumption of all the gadgets one needs and calibrating the number of panels needed. In a conventional house, we mindlessly plug any appliance and pay for the usage. For instance, if Alok and Nina wanted to get a microwave, they could still use one, provided they added an appropriate number of solar panels. The other is to switch on power-intensive motors, like the washing machine, when the sun shines instead of draining the batteries at night. More sophisticated solar homes are computerised to tell how much energy is coming in, which appliances can be run, and suggest when to run them.
Nina and Alok’s house is an integrated unit, which produces energy, water and to some extent, even food. It also makes budget-sense. It cost Rs 900 per sq ft. for the entire infrastructure, not including the solar energy system and windmill. A conventionally built house in the same area cost up to Rs 2,500 per sq ft to build at the same time. This doesn’t include the septic tank, water treatment or storage. That the house withstood Cyclone Thane and emerged unscathed testifies to its durability and vindicates the couple’s belief in treading softly on earth.
(TOICREST21JAN12)
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