Taaron ko dekh te rahein,
Chat par pare huye.
– Gulzar
The popular Hindi movie song of ‘Mausam’ beginning with a couplet by Ghalib, lyricist Gulzar fondly recalls the bliss of seeing the stars by laying idly on the terrace — an experience everyone cherish to have on hot summer nights in India.
In Assamese folklore, there is an opposite feeling of loss or deprivation while seeing the stars through the tattered thatched roof of traditional houses (urukha saalere akashor tora goni goni…). It implies the nocturnal experience of a poor person who could see the stars in the sky through the pierced/tattered roof of his or her house.
Though the poorest of the poor could not afford to repair his tattered thatched roof for which the starry night was visible from inside or rain drops come in the monsoon, the thatched roofed houses— called Kheri Ghar have been a nature’s wonderful gift to people in Assam and the entire North-East region of India in providing a heat resilient and comfortable living.
The thermal insulation thatch:
Kher Ghar is a house whose roof is thatched and made from Kher (Imperata cylindrical) commonly known as cogon grass of perennial rhizomatous grass, native to tropical and subtropical regions that grows abundantly in the Brahmaputra valley. Also known as blady grass, spear grass or sword grass for its finely toothed margins and with embedded sharp silica crystals Kher was the inseparable part of vernacular architecture of traditional Assam type houses till 1980s along with bamboo, Eikora and mud.
Ripe green Kher was cut and dried in sun till they turn brown and kept in bundles to be used for roofing. Bamboo beat flattened and cut long are framed crossing each other like a mesh are put on the roof to be used as purling. On that purling the bundles of Kher are knitted to make the thatched roofing. The work of roofing in traditional Assam Type housing is called Sawney.
Usually a Sawney lasts for two-three years and after that it requires minor repair works and additions of new Kher if not damaged by external factors like tree falling, heavy storm or other calamities.
There was a standard system of a bundle of Kher determining the sustainability of the roofing work Sawney in the traditional housing technique. If the bundle is as long as that of a hand, the roofing work would be very strong and long lasting.
The most effective part of the Kheri Ghar is that it is very heat resistant and a great comforter in winter. The Northeastern states including Assam experience a considerable amount of heat ranging from 35 to 40 degrees during the peak summer time.
The damp and humid condition of the climate with the increased heat of the summer has been adding misery to people living in households of modern architecture. Mostly the houses with galvanized iron sheet, in which most of the people live radiates more heat inside.
Ceiling with asbestos or plywood or other processed materials are put to insulate the indoor heat in such houses of no desired results. But a house with Kher on its roof keeps inside cool even without any ceiling. And a traditional Assam Type house with Kher roof, Eikora ceiling with mud plaster or without plaster and mud-plastered walls works as an Igloo does in Arctic — keeping the inside temperature in comfort while the outside one is extreme.
A distinct pattern lost:
The Kheri Ghars were the only type of houses in Assam so far as roofing was concerned in vernacular architecture when the British colonized the region in 1826. The British colonial administrators followed the same vernacular technique of thatched roofing in their constructions for comfort and to beat the heat in Assam — which then comprised of almost entire present-day Northeastern states.
All the bunglows of tea estates, district administrator’s residences, educational institutes and other public halls were all Kheri Ghars till the mid-twentieth century in Assam and many of its neighbouring states.
The official residence of the Principal of Cotton College, Guwahati, founded in 1901 remained with its Kher roof till 1983. In many suburban areas also people used to keep a Kheri Ghar in their campuses and used as kitchen, Dheki Ghar (grinding house) or as store room till the 1990s.
But the narrative of development and upliftment exemplified by RCC houses created a sense in the society that living Kheri Ghar was something of inferiority. Thus we have lost a great tradition of comfortable housing supplemented by eco-friendly and locally available materials to industrial products that have now a major source of heat generation.
Realizing this eco-friendliness and comfort with locally available materials, promoters in Assam have been using Kher roofing in many tourist resorts and cottages in the hospitality industry. People are paying a lot to stay for a night in these resorts built with Kher, bamboo and mud.
However, the biggest disadvantage of Kheri Ghar is the flammability of the grass plant. Kher is highly flammable even in its raw form in the vegetation and till 1980s there was a regular firing incident on Diwali nights in Assam every year.
Kheri Ghar does not require skilled labour or and very cheap due to its local availability and can be an answer to climate-induced heat radiation for the affordable housing sector.
The Portuguese connection:
In April, 2019 Gharaunda, a housing initiative by Drishtee Foundation offering sustainable housing solutions to the marginalized communities, was launched in Assam with the setting up of a housing typology using treated bamboo.
Constructed with a design by Portuguese architect Phillip Estella and Sarah the typology has a strong and durable concrete plinth, three layers of roof of Kher, galvanized sheets and reeds for better temperature, insulation and acoustic convenience, double walls for structural strengthening.
Thermal insulation was designed as a model for low-income families costing less than three lakhs and could be completed in less than three months. The house also has features like attached toilet, clean water source, fireproof kitchen, additional floor as room or store and three-sided verandah.
This affordable house model with thermal insulation was presented to the office of the Prime Minister for housing schemes like PMAY for which rural poor could access affordable housing made from locally available material for sustainable development.
(The story is being published as part of CMS-BEEP Media Fellowship Program)