When the topic of marine waste comes up, it is often associated with what is immediately visible, like plastic debris, ghost nets, and abandoned fishing gear that wash up along coastlines, serving as stark reminders of human-caused ecological neglect. Yet, beyond what reaches the shore lies another, less acknowledged layer of waste tied to maritime economies. In port cities, unused shipping containers, discarded after their lifecycle, accumulate in industrial yards, often stripped of purpose when the cost of repair outweighs their value after years of heavy use. These massive steel units, however, are beginning to find relevance in an industry far removed from their original function — construction. With their inherent modularity and structural robustness, they present a compelling opportunity for adaptive reuse. In India, such containers have long been repurposed as site offices, training facilities and residential quarters in industrial settings, and even as homes. Entering this narrative is Petti Restaurant, which reimagining discarded containers as the foundation for a contemporary, climate-responsive eatery.
Built in Thoothukudi, a historic port city in South India, the sheer number of discarded steel shipping containers in the region naturally influenced the design approach of architect Vinu Daniel, founder of Wallmakers, and architect Oshin Mariam Varughese.
“We are a firm that mostly uses discarded materials wherever possible. We started working with a material called compressed stabilised earth blocks,” says Oshin. “But over the years, we understood that using just mud is not always the right way to go for every site, especially when there is a different context while building in different parts of India and abroad. So we have to think on our feet.”
Hence, for this project, this meant turning to what was abundant. “Once we changed our outlook and this project came, we found that one of the most discarded materials there (Thoothukudi) is shipping containers,” she says. Petti Restaurant, designed for a narrow and linear plot, uses 12 containers that were sourced locally, cut, and stacked to form the structure. While modularity offered flexibility, it also posed spatial challenges. “Containers are typically used horizontally, which results in a more congested space with a room height of about 2.4 to 2.6 meters,” Oshin notes. To overcome this, the design adopts a vertical stacking system to achieve a larger volume, resulting in a standard 3 m single-floor height. This move not only improves spatial comfort but also permits ventilation, she adds.
The interiors are carefully articulated to balance compactness with intimacy, with each family or each person having a small niche. The planning ensures that even within a constrained layout, users experience a sense of privacy, aided by natural light and the use of raw and natural materials that retain the original character of the containers.
Yet, the primary challenge lay not in space, but in climate. “When you are using steel in a tropical climate, heat is a problem,” Oshin notes. Addressing this required a material intervention. After research and development, Vinu and his team came up with the solution in the form of a poured earth façade layered over the containers. “We wanted to protect the steel surface from overheating, which is how the mud façade came into the picture. The steel shell has been welded together and arranged in a position, and then we added a mud façade on top of it in a pattern that partially recesses so that it adds air pockets to give thermal insulation,” she explains.
For the past two decades, Mahatma Gandhi’s advice to Laurie Baker — an architect known for his cost-effective energy-efficient architecture — has led the Wallmakers to rethink material sourcing: The ideal home should be built using materials available within a five-mile radius. “We didn’t want to dig up some other hill from another corner, bring up the soil to our site, make the mud blocks and then call ourselves sustainable. To be really sustainable, we are talking about embodied energy,” Oshin says. She adds that around 80 to 90 per cent of the materials that they use for any project come from within a five-mile radius, and to avoid compromise on aesthetics or the overall experience, about 10 per cent of certain materials, like glass, are sourced.
Questions of longevity were also addressed through careful detailing. “Mud has been around forever. If you look at some of the oldest structures in the world, which are still standing today, it’s all built entirely with mud,” Oshin says. However, the interaction between steel and mud required additional protection. “Steel and mud are not the ideal combination, as there is a chance of expansion if the steel is not protected. So we have coated the container surface with multiple layers of protection to prevent any outside exposure to rusting, as it is directly exposed to rain and sun,” she explains.
The client’s collaborative role was equally significant in shaping this project. In this case, they were closely involved in the process, contributing to material sourcing and design decisions, particularly in the interiors, where elements like lighting fixtures — a chandelier with old wax and pipes — were developed.
Beyond its immediate context, Petti points towards a larger architectural possibility. With port cities across India facing similar conditions of material surplus, the project suggests an alternative way of building that engages with industrial waste as a resource rather than a by-product. “India has a lot of port cities, and after a certain lifetime, these shipping containers are eventually discarded,” Oshin notes. Having addressed both spatial and climatic constraints, the team sees potential for broader applications. “Now that we (Vinu and the Wallmakers) have figured out the way to increase the volume for more space, we are doing research on how we can even bring down the temperature even more with respect to containers, but we believe that this is a suitable material because of its modularity and has got a lot of advantages for high-rise buildings or for even larger housing scenarios,” she adds.
Petti Restaurant extends the conversation on sustainability beyond surface-level interventions. It proposes a shift in perspective where architecture begins not with the search for new materials, but with a closer look at what already exists.