Sachin Rastogi of ZED Lab on the essentiality of sustainability in India

When we look at the western side of the world, our developed counterpart, it is easy to spot styles, influences, and inspirations, whether in indulgence or in minimalism. In the presence of ample resource supply and highly skilled labour, innovation may be originating from anything between the paper and the pillar. When not aping the West’s still largely modernistic sensibilities, the story in the eastern hemisphere, (barring China, of course, that is now home to some world class architecture) is a little different. Innovation here stems in the face of restraint and resource limitation. Style becomes a manifestation of how effectively one can work backwards from these limitations, and champion them into bearing a signature aesthetic. That has largely been the definition of an ‘Indian’ architecture and style, rooted in decades of vernacular history and culture, followed suit by some stunning new architectural interventions in the subcontinent and other countries in South East Asia: Vietnam, Bangladesh, Thailand, and Indonesia among others.

The above mentioned practices are largely synonymous for sustainable architecture in its truest, most holistic sense: an intrinsic, incorporated practice rather than an imposed one. New Delhi-based ZED Lab and its founder architect, Sachin Rastogi, imbibe that adage as they look to formulate a bridge, inspired from the vernacular and the aged, realised using tools that are cutting edge. Rastogi talks with STIR about his journey and pursuit, and about how the two stylistically and temporally different schools of thought enable each other rather than contradict, in his search for an architecture that can be called quintessentially ‘Indian’.

Edited excerpts from the interview:

Anmol Ahuja (AA): Is there a defining moment or experience that cemented your pledge towards energy-conscious design? Does it play a part in reaching ZED Lab's current ‘style’ or language of architecture?

Sachin Rastogi (SR): It can be said that there were two such instances in my life. The first was the great influence Mr. Ashok B Lall's work had on me. Learning about his projects through case studies helped me truly appreciate his designs and understand their user-centric value that goes beyond aesthetics. The second defining moment was working with BDP International in the UK, where the mantra was to ‘Measure, Minimise and Mitigate’. Here, I learnt that only by using the first M - Measure, the dependency on the others could be reduced. It was from here that my passion for energy-efficient design was sparked and the foundation for Zero Energy Design Lab was laid.

AA: Which architects and/or designers would you say have had the most telling influence on your idea of architecture?

SR: Readings by Giovanni, Susan Row, Le Corbusier, and Ashok B Lall’s work.

AA: There is a considerable shift in practices and thoughts that you may have noticed with respect to architecture and its notions, shifting back home from your time in Europe and overseas. Which was the most significant one?

SR: In Europe, budget was not much of a criteria or constraint. What you envisaged on paper could be built on site with a team of skilled professionals who translated your ideas into reality. Hence, experimenting with new designs was possible. In India, it is a completely different scenario where we need to fight a lone battle regarding budget constraints, on-site delivery issues, unavailability of skilled labour etc. Another significant challenge is adapting to the different social and climatic conditions in the Indian context. Since user behaviour and patterns are different in the two countries, spaces need to be designed appropriately to serve this contrast.

AA: What is the absolute first step in your creative process? How does it manifest into a vision that you can claim to be close to final?

SR: People and place specific architecture holds the key to our design process. Response to climate, context, materiality, user patterns, typology of spaces and so on, remain the guiding principles in each of our projects.

AA: How did you come to develop and imbibe ZED Lab’s 3M approach: measure, minimise, mitigate? Do you think it is also adaptable as a universal rule on achieving thermal comfort in buildings?

SR: I learnt it from my head at BDP London, Mr Butler. I strongly believe in the 3Ms and eventually have adapted it to suit my work in India. It is a good rule of thumb and can be implemented at a universal scale as it caters to energy, finances and applicability in a building.

AA: You have talked about seeking inspiration in traditional Indian elements such as jaalis and jharokhas for passive measures in architecture. How do you mold or reinterpret these to align with modern sensibilities?

SR: Our country’s architecture has, for centuries, employed design mechanisms for energy efficiency. And while vernacular will continue to echo the identity of Indian architecture, adapting such techniques alone may not be able to deliver efficient, long-lasting, and resilient solutions to suit the diverse needs of the present and the future. Thus, reinterpreting principles from vernacular architecture to guide design, through modern and innovative tools such as parametric design holds the key for creating environmentally compatible and economically viable buildings.

The modern vernacular can be explored through computational tools across diverse scales and typologies within the built environment. For instance, for the Girls’ Hostel Block at the St. Andrews Institute of Technology and Management, we developed a pigmented hollow block façade (that takes from the jaali), modified from the previously developed façade that spanned the adjacent boys’ hostel within the institute. The efficiency of the previously built façade was analysed in terms of thermal mass, solar radiation etc. through computational software, which then accordingly guided the rotational angles of the blocks for the new proposed façade. In this sense, parametric tools not only helped in developing a new design but also illustrated earlier shortcomings.

AA: Is it true that the cost implications of sustainable architecture may sometimes be higher than conventional, non-responsive architecture? How do you get your clients to be on board then, with the same enthusiasm for energy-efficient buildings? 

SR: Contrary to common assumptions, a ‘near net-zero building’ (built to minimise net energy; one that strives to be net-zero) does not need to be expensive to construct and run; such a building is designed to work with its climate and context. In addition to the significant role of natural lighting and ventilation, an energy-efficient building relies on the use of passive design strategies which can, for instance, cut down solar heat gain by almost as much as 60-70 per cent. These include using locally available materials that are affordable and have high thermal mass as well as specific design elements such as indoor green spaces and water bodies that create a cooler micro-climate. Figuring out how to limit the use of air-conditioning and assessing the ways we can maximise natural ventilation indoors, for instance, is another way of optimising users’ cooling needs.

While near net-zero buildings may also rely on systems that harness renewable resources such as solar panels which have higher initial costs but are offset with the energy savings over time, designing concisely through passive design can actually minimise or even eliminate the need for adopting such active measures. Adopting these, we have executed the design-build construction for institutional buildings at ZED Lab in the price range of INR 1500-1800/sq. ft.

Contrary to common assumptions, a ‘near net-zero building’ does not need to be expensive to construct and run; such a building is designed to work with its climate and context.

AA: Do you agree that there is a fair degree of pretence when it comes to sustainable architecture today, that it is often used as a catchphrase, a marketing slogan as opposed to actual application? How do you make sure not to fall into that trap?

SR: Indeed, sustainable design ratings can often be a rat trap. Sometimes you are forced to take steps which do not abide by the policy and the ratings can be faux. Moreover, there is constant pressure to market the certification. Therefore, one viable alternative is to replace the rating with Energy Performance Index (EPI – the total energy consumed in a building over a year divided by total built up) from the Energy Conservation Building Code (ECBC). This is a genuine number which a building cannot fake; the audit, furthermore, should be done by a third party.

AA: Sustainability is a holistic pursuit. Do you see some of your maxims in design trickling over to your daily life?

SR: Sustainability is not an added construct; it is a way of living. I was brought up in a household that has long been embracing a sustainable lifestyle within daily routines. Our house never required lighting or air-conditioning during the day. Our bodies adjusted to higher temperatures through the principle of adaptive comfort: the idea that people experience indoor conditions differently and adapt accordingly allowed us to adjust to a variety of temperature conditions by virtue of tolerance. Instead of relying on refrigerators, we used earthen pots or matkas to cool drinking water. These practices were not driven by a green building perspective or a socially and environmentally conscious approach, but from an economic perspective as well. They encouraged conservation of resources and avoided wastage. Our way of life back then provided both the time and the resources to think of and invest in innovative ways of living sustainably.

When it comes to enabling such living through architecture, the role of sustainable design that prioritises energy-efficiency assumes immense significance. Additionally, for us, sustainability is not an isolated layer in design, but an indispensable component that enhances the experience of the built environment. Fundamentally, it calls for designing in tune with nature, the site, and climate.

Sustainability is not an added construct; it is a way of living.

AA: What advice would you lend to young professionals venturing into the field of energy-conscious design? Is there a definite skill set that you would state is essential to pursuing a career along those lines?

SR: Young individuals should definitely venture into the realm of user-centric, conscious and adaptive design. Climate change is an extremely pressing issue today and it does not take a professional to understand its intricacies: it is something for everyone to think about collectively and work towards resolving. The built environment is responsible for a considerable portion of the causes of climate change and biodiversity loss, contributing almost as much as 39 per cent of the carbon emissions produced globally. In our efforts to fight against climate change and lower our carbon footprint as individuals, there is an urgent need to design net-zero buildings with a minimal carbon footprint. Thus, as architects and designers, improving energy-efficiency in the built environment should take centrestage.

AA: How are you looking to STIR up 2021?

SR: Being in the middle of a pandemic, the struggles are real, but doing what we love, making exemplary buildings that stand the test of time is the motto for 2021.