Architecture

KNOW WHATS INSIDE YOUR WALLS: EARTHEN PLASTERS

enrouteI
August 4, 2023

The walls that surround us have seen the passage of time, silently bearing witness to the tales of generations past. Yet, beyond their mere function of dividing spaces, they also hold history, starting from the days of mud houses and plasters, to today’s cemented structures. Architecture holds an indelible significance in historical study, unveiling a treasure trove of insights into our past. Within them lie the secrets of ancient techniques and eloquent storytellers, narrating the intricate relationships between far-off empires. They also give you a glimpse into lost ancient wisdom and secret ways to harmonise with nature. Ancient civilizations ingeniously adapted to their surroundings, utilising locally sourced materials and harnessing natural elements to create eco-friendly structures that stood the test of time. One of these elements was the wall plasters.

MUD PLASTERS IN INDIA

The history of wall plasters in India dates back thousands of years, with evidence of early usage found in ancient archaeological sites. One of the most iconic examples is the Ajanta and Ellora Caves, where intricate plasterwork can be traced back to the 2nd century BCE. Traditional plasters were made by mixing lime, sand, and water, and they were applied to walls, serving both functional and decorative purposes. Over time, different regions developed their unique plastering techniques and styles, reflecting the diverse architectural heritage of India.

One of the most iconic examples is the Ajanta and Ellora Caves, where intricate plasterwork can be traced back to the 2nd century BCE.

Mud plasters or earthly plasters remained the norm till the mid 20th century. During the 19th century, with the arrival of the British also came cement. The colonisers spent extensive resources on building Indian infrastructure such as railways, buildings, etc. using European standards and materials. The initial use of cement in India was primarily for large-scale infrastructure projects, but its applications soon extended to various construction practices, including plastering. As cement production technology improved and became more accessible, it gradually replaced traditional plastering methods in many parts of the country. Portland cement, the most common type of cement used today, was invented in the 19th century in England.

Nonetheless, in Indian villages, plastering techniques have been an integral part of traditional construction for generations. These techniques are rooted in the local environment, culture, and available resources. The basic components of these plasters are clay, stone dust and sand, often mixed with an additive that provides a specific benefit. These additives vary from region to region as per environmental and physiological requirements. The sand helps provide a construction basis while the clay acts as the binding agent.

A woman pastes cow dung cakes on a wall as her grandson Sanju peeps from a hole in Molaya village on the outskirts of the northern Indian city of Chandigarh March 2, 2010. REUTERS/Ajay Verma

The second kind of natural plaster used is the lime based mixture. The latter is, in fact, preferred due to its waterproof properties. Thus, clay based plasters were used for interiors while the lime based ones were used for exterior walls. Lime plaster provides a breathable surface that allows moisture to evaporate, preventing issues like mould and mildew growth. It is suitable for areas with high humidity. Clay plaster is known for its excellent thermal properties, making it suitable for varying climates. Cow dung plaster is a traditional technique used in some Indian villages. Cow dung is mixed with clay and water to create a paste that is applied to walls. Despite its unconventional nature, cow dung plaster offers several benefits. It acts as a natural insect repellent, keeping pests away from homes. Additionally, it promotes recycling of agricultural waste. India’s arid regions have long relied on mud plaster or adobe plaster. They are suitable for hot and dry climates and have excellent thermal mass properties, which help regulate indoor temperatures. In certain regions of India, such as Rajasthan, marble dust plaster is preferred. It involves mixing marble dust with lime and water, resulting in a smooth and glossy finish that resembles marble. This luxurious plastering method is often used in palaces and historical monuments to create an opulent appearance.

The architecture also varied from place to place. In the Chettinad region of Tamil Nadu, masons carry an age-old technique of adding egg whites to their clay mixtures. These benefit them in creating a shiny firm finish to the walls. These walls also don’t require constant repainting and help beat the scorching heat. Similarly in the rural lands of Bisoi, Odisha, women play a key role in the making and upkeep of houses. They prepare the daub from a mix of red and black soil which is then applied on a wooden structure. This technique is also referred to as ‘wattle and daub’. Women are, in most cases, responsible for procuring and assembling the material. They plaster walls and floors with elaborate mixes using cow dung that protects them from harsh climates.

These traditional plastering techniques in Indian villages demonstrate the wisdom of adapting construction practices to local resources and climatic conditions. They reflect the sustainable practices that have been passed down through generations, promoting harmony with nature and minimising the ecological impact of construction. In the captivating region of Gujarat’s Kutch, the Bhunga houses stand as a remarkable testament to the local heritage. These circular mud-based structures adorned with elegant dome-like bamboo thatched roofs have endured for nearly two centuries, serving as not only charming dwellings but also resilient fortresses against seismic activity and harsh winds. In rural India, paintings on mud houses, also known as wall paintings or mud murals, are vibrant expressions of cultural identity and creativity. Adorning the exteriors and interiors of mud houses, these artworks depict religious symbols, folk stories, and scenes from daily life. Created using locally sourced natural pigments and hold deep cultural significance, playing a role in festivals, rituals, and special occasions.

In the captivating region of Gujarat’s Kutch, the Bhunga houses stand as a remarkable testament to the local heritage. These circular mud-based structures adorned with elegant dome-like bamboo thatched roofs have endured for nearly two centuries, serving as not only charming dwellings but also resilient fortresses against seismic activity and harsh winds. Picture Courtesy : D’Source

THE PATH TO SUSTAINABLE FUTURES

The practice of mud plasters is cost effective and its resources are readily available. Yet, with the introduction of cement, these practices declined. Cemented houses became synonymous with development, while mud-based homes were stigmatised as symbols of poverty. Despite cement’s advantages in durability and versatility, its environmental impact is concerning. The production of cement releases significant greenhouse gases, its walls lack breathability, and they contain toxic chemicals that can pollute the indoor environment over time. Recognizing the need for sustainable solutions, homeowners are now turning to naturally sourced structures. Experts are championing natural building materials as the answer, drawing inspiration from ancient Indian techniques used in the Karla and Bhaja Caves’ plastering.

Amit Upadhyaya, WebIndia123

Organisations like HUDCO and private companies like Thannal Homes strongly advocate for “natural homes” as the way forward towards a more environmentally friendly approach. Amidst the escalating concerns of global warming and climate change, it becomes imperative to embrace the wisdom of old practices. Reigniting the study and adoption of mud plasters emerges as the most promising path forward. By returning to these time-tested techniques, we can take a significant stride towards creating a more sustainable and eco-friendly future.

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References:

Sriraman, S. 10 Indian vernacular finishes that are disappearing. *Re-thinking the Future*.

Dighe, B., & Singh, M.R. (2020). Ancient Indian techniques for sustainable and environmentally friendly decorative earthen plasters of Karla and Bhaja Caves, India. *Materials Today Proceedings*.