“Mud is kaccha (raw).”
“Sustainable architecture isn’t pretty.”
Architect Guruprasad Rane of the firm ‘Bhoomija’ in Kerala would often hear some of these opinions being shared by his clients who wanted a new space built for them. “But now that is slowly changing,” he says.
“Clients these days are open to sustainable alternatives of construction. In many cases, clients have approached us with a conventional cement design in mind. But we have introduced them to cob, soil and other materials that could work well,” the architect shares.
In tune with this, The Better India sat down with a bunch of architects who disproved the belief that cement is the only material suitable for construction. They believe it is time to do away with such ideals and make way for more planet-friendly perspectives.
The architects in this piece converge on a verdict that responsible design and great aesthetics can indeed go hand-in-hand. Keeping conscious design at the fore, they are building a new India — one that is in tune with sustainability.
We deep-dived into their projects and understood the ethos behind each material used. Here are five that impressed us —
1. Rammed earth
The residence of Dr Achutshankar in Karyavattom, Kerala, always draws two glances from any onlooker. The first is because of its beautiful, rust-coloured exterior that perfectly compliments the mud on which it stands, and the second is because people can hardly believe the structure is built out of soil.
Standing proud of their creation are architect duo Guruprasad Rane and Manasi Puliyappatta, the brains behind the sustainable architecture firm ‘Bhoomija’.
Speaking about the use of rammed earth in the construction, Rane notes that it isn’t something novel. “The usage dates back to the Neolithic age. Recent demand for sustainable construction has led to renewed interest in this technique,” he notes.
About the material: Soil, sand, gravel, clay, and a stabiliser come together in a damp mixture to form ‘rammed earth’ that is moulded into the desired shape. For the residence in question, Rane says the soil was procured from a 60 cm depth and cleaned using a mechanised sieve to remove organic matter like roots and stones.
In the recent past, there has been a collective push encouraging the use of the material. Rane cites its abundance as the reason for this push.
“In most cases, it is available on-site making this one of the most sustainable methods of construction,” he shares. The fact that it leaves no debris behind is another boon.
The architects are often complimented on the timeless charm that the residence exudes. They credit the walls for this. “They are breathable and porous because of the rammed earth,” Rane points out. He adds that this quality also helps the home regulate its temperature and humidity levels.
A March 2023 research study published in Science Direct aligns with what the architects claim. Underlining the advantages of using rammed earth, like the decrease in the environmental and economic costs related to transportation, the reduction in industrial processing required, and the material’s thermal-mass technology, the article is a nod to the material’s sustainable quotient.
Architects, take notes: Having worked with rammed earth for multiple projects, Rane cautions architects who are planning on doing the same. “Pay attention to the soil composition,” he says. “This varies at different locations at the same site; the proportion of soil mix needs to be adjusted accordingly.”
He adds that roof overhangs should be installed around the homes made out of rammed earth, particularly those located in rainfall-prone regions. This is because the walls made of rammed earth need protection from the rain.
2. Timber
When the team at SJK Architects — a Mumbai-based architectural firm that has spent the last three decades designing spaces — was approached with an ask to design a retirement home and skill centre in Awas, Alibaug, they were keen on it having a sustainable touch.
Timber was the choice of material but not in its raw form. The architects decided to use Glue-Laminated Timber (GLT) and Cross-Laminated Timber (CLT) for the construction. These engineered woods, they say, see multiple layers of timber bonded together with durable, moisture-resistant structural adhesives.
About the material: What separates GLT from CLT is that in the former, laminates of structural timber are layered and glued in the same direction, on top of each other, while in CLT, each layer of timber is glued at 90 degrees to the layer above and below.
But, timber is wood, you point out. Is building with it sustainable? Sarika Shetty, one of the architects involved in the project responds by saying that this is where procurement comes into play. “It is crucial to ensure that the timber is sourced from certified, sustainably managed forests, even if it means sourcing from abroad. Utilising sea travel for transportation can significantly reduce emissions compared to air freight,” she shares.
In a research paper published in 2023, the advantages of timber were assessed in comparison to its counterpart materials such as steel and concrete. The findings concluded that timber produces lower carbon emissions and has a lower environmental impact in contrast to the other materials.
And the architects agree. Elaborating on the use of CLT and GLT, they share that these are carbon-negative (emit less than zero CO2 equivalents) and thus renewable, provided the timber is sourced from sustainably managed forests. It is tolerant to warping and cracking, making it an excellent choice of material.
Shetty adds, “We have seen that CLT buildings have less than half of the embodied CO2 of conventional reinforced concrete buildings.” Their light weight, she says, reduces the foundations’ overall weight and allows for easier construction, handling and transportation.
Another perk is that CLT and GLT are made from softwoods. “So, they can be impregnated with chemicals to make the timber termite-proof, an advantage not typically found with hardwoods,” says Shetty.
Architects, take notes: Shetty encourages architects to go in for species such as Douglas Fir and spruce pine fir which offer a lightweight alternative to traditional Indian hardwoods.
3. Ventilated terracotta
Picture a construction material that keeps the structure cool in the peak of Indian summers, provides acoustic insulation (cuts noise levels by up to 15 percent) and looks pretty!
Architects of firm GPM Architects and Planners were as amazed as you are when they worked with ventilated terracotta tiles to design the Defence Office complexes in KG Marg and Africa Avenue, Delhi. If you pass by, you’ll agree. The campus makes for a beautiful tapestry with the terracotta tiles stealing the limelight.
Elaborating on how the 9.60 lakh sq ft area was completed in 10 months using pre-engineered technology, the architects say the terracotta made it easy.
Did you know the material’s use traces back to the Harappan Civilisation (3300-1300 BC)? A 2024 research study published in the International Journal of Novel Research and Development highlighted the eco-benefits of terracotta pointing to its energy efficiency.
“The firing process used in terracotta production typically requires lower temperatures compared to other ceramics and building materials like concrete or metals. It has reduced greenhouse gas emissions,” the paper noted.
About the material: The architects behind this construction concede that ventilated terracotta tiles are low-maintenance materials. “By reducing solar heat gain, decreasing the air conditioning load, they save up to 30 percent energy costs.” Because of their thermal insulation capabilities, terracotta tiles reduce heat transfer into the building, thus maintaining a stable indoor temperature.
Made from clay, which is naturally available in abundance, terracotta has a low carbon footprint and is recyclable.
Architects, take notes: Ensure that the material’s thermal insulation aligns with local conditions, architects say. Sharing some precautionary advice, they say that terracotta adds to the weight of the facade. Hence structural support is essential. They also pointed out how, in this particular design, adding proper ventilation behind the cladding went a long way to prevent moisture issues.
4. DGU glass
A marker for good aesthetics is how architect Vineeta Singhania Sharma of Confluence — an architectural firm founded in 1999 — describes this material. It formed one of the principal elements in the design of the Food Safety and Standards Authority of India (FSSAI) office at Indirapuram.
Picture two panes of glass filled with a buffer of air in between. This is how the material appears.
About the material: The use of the DGU (Double Glazed Unit) glass in the office space optimises the daylight, allowing natural light to penetrate. Sharma adds, “It [DGU Glass] has excellent thermal insulation properties and maintains a more stable internal temperature, reducing the reliance on heating and cooling systems. This leads to significant energy savings and a lower carbon footprint.”
The insulation capacity extends to noise too. “This is particularly beneficial in urban areas or near busy roads,” she points out.
Architects, take notes: Since the material works to insulate spaces, the climate of the region needs to be kept in mind. “In addition to this, structural considerations need to be made to ensure the building can support the weight and thickness of DGU glass,” says Sharma.
5. Clay bricks
The work of American architect Louis Kahn was considered edifying by devotees of sustainable architecture. The imprints of his design philosophies are in the Indian Institute of Management at Ahmedabad.
He was acclaimed for his abstract constructions that featured vast brick walls and geometric voids, and his ability to capitalise on the Sun’s shadows. It is with Kahn’s architectural mindset in view, that architects Amit Khanna, Ankita Misra, and Krishna Yadav of Amit Khanna Design Associates (AKDA) have designed a residential space in New Delhi.
About the material: Clay bricks are the heart of the construction. Versatile to use, these are durable and can withstand distinct weather conditions, the architects point out. The fact that they are locally available, can be combined with other materials such as glass or wood, have longevity and are cost-effective, makes them a great option.
Architects, take notes: “Clay bricks can be used as building blocks to create numerous partitions, screens, or surfaces. For the same, architects need to consider the structural integrity and the construction method of the proposed structures,” Khanna emphasises.
These architects and their projects are illuminating the way for sustainable urban planning. Through their work, they are crafting a new mindset and identity for sustainable architecture.
Edited by Padmashree Pande
