Designing for Feeling, Not Fahrenheit: A New Perspective on Thermal Comfort
- SJK Architects
- Oct 18
- 7 min read
Write up by Vaishali Mangalvedhekar
Thermal comfort is as much a psychological experience as it is a physical one. In the spirit of sustainable architecture, SJK design approach acknowledges that our expectations deeply influence how we perceive temperature.
As Vaishali Mangalvedhekar notes, our increasing reliance on air-conditioning has disconnected us from natural patterns of adaptation—making buildings, and by extension, cities, hotter and less sustainable.
On a warm Sunday morning in Alibaug, I sat on a verandah, surrounded by the still, humid April air. The temperature read 27°C, but it felt like 29°C. There was no breeze, yet the setting felt calm, even pleasant. The next morning, back in my Mumbai office, the same 27°C felt stifling. Almost instinctively, I reached for the AC remote. It made me reflect on thermal comfort and how dramatically our perception of it can shift, even under seemingly similar conditions.
Comfort Begins in the Mind
The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) defines thermal comfort as “that condition of mind which expresses satisfaction with the thermal environment.” In other words, thermal comfort is subjective and contextual, shaped by an individual’s perception and the specific conditions of their surroundings.
Yet, building codes such as ASHRAE and India’s Energy Conservation Building Code (ECBC) often reduce thermal comfort to measurable factors — air temperature, humidity, airflow, and metabolic rate. While useful, these metrics treat humans as passive recipients rather than active interpreters of their environment.
While these metrics are useful, they treat the human body as a passive recipient of environmental conditions rather than an active interpreter of them. In doing so, they overlook the nuanced ways in which culture, conditioning, and context influence how we perceive heat or cold. A truly sustainable design approach must move beyond these numbers — embracing the psychological, cultural, and climatic dimensions of comfort. It recognises that designing for comfort is not merely about achieving prescribed thermal standards, but about restoring our connection with natural adaptation and resilience - principles evident in projects like Sparkrill International School, where architecture and nature work together to enhance learning and well-being.
How Perception Alters Comfort
Our perception of comfort is shaped as much by expectations as by actual temperature. At the resort in Alibaug, I was outdoors and mentally prepared for warmth. Surrounded by open spaces and nature, I anticipated a certain level of heat, and my clothing, activities, and mindset were aligned with that. As a result, 27°C in Alibaug felt natural and easy to adapt to. The same 27°C back in my air-conditioned Mumbai office felt unpleasant, simply because my mind expected a cooler, conditioned environment.
Over the years, we’ve grown used to associating thermal comfort with air-conditioning. Since the 1980s, as air-conditioners became more affordable, commercial buildings in India began to mimic the glass towers of the West. As a result, we’ve internalised thermal comfort standards rooted in colder climates, routinely setting our thermostats to 22–24°C regardless of our own context or climate.
In his seminal lecture “A Place in the Sun,” the internationally acclaimed architect Charles Correa questioned the blind copying of Western building models. He pointed out that this approach often ignores local realities — the intense sunlight, high humidity, daily routines, and energy considerations that shape how people actually experience a space. Buildings that aren’t designed with these factors in mind tend to rely heavily on air-conditioning, feel disconnected from their surroundings, and can be uncomfortable for those using them. Correa encouraged architects to design in harmony with the local climate, culture, and lifestyle rather than importing standards from elsewhere. This idea lies at the heart of sustainable architecture, which seeks to create spaces that are not only energy-efficient but also naturally comfortable and responsive to the people who inhabit them. I believe that,
In doing so, we end up designing spaces where comfort is engineered, not experienced, and where our perception is slowly trained away from the richness of sensory connection to our surroundings.
Heat Resilience is Cultural: Comfort Thresholds Can Shift With Exposure
Heat resilience — our ability to cope with rising temperatures — is not just biological, it’s cultural. Habits, lifestyles, and the environments we grow up in shape how we experience heat. People in tropical regions, living in outdoor or semi-open settings, naturally develop higher tolerance through repeated exposure.
A 2017 study by Titis Wijayanto et al. highlighted this adaptability. Malaysian students, familiar with high-heat environments, tolerated heat stress better than their Japanese counterparts under the same conditions. Yet the human body’s capacity to acclimatise shows that comfort thresholds are flexible; what feels unbearable initially can become tolerable with time and exposure.
We adjust instinctively — choosing lighter clothing, slowing down during peak heat, or seeking shade. This everyday adaptability illustrates a key principle of sustainable design: buildings should work with human behavior and natural climate patterns, not against them. By embracing these strategies, sustainable architects create spaces that enhance comfort while reducing reliance on mechanical cooling. Thoughtful design — from shaded courtyards to cross-ventilated classrooms — nurtures well-being, energy efficiency, and a deeper connection between people and their environment.
The Equatorial School in Singapore: A Case Study in Thermal Comfort Adaptation
During a visit to Singapore, I experienced the Equatorial School at NUS, designed by Erik L’Heureux — a perfect example of how sustainable design can work with human adaptability. Despite Singapore’s heavy reliance on air-conditioning, over 65% of the building is hybrid-cooled or naturally ventilated, while optional AC zones maintain slightly higher temperatures, encouraging students to recalibrate their sense of comfort.
Circulation spaces such as corridors and stairways are left entirely naturally ventilated, becoming vibrant social zones that engage directly with the tropical climate. The west façade acts as a climate-responsive veil, reducing heat gain and demonstrating how sustainable architecture can transform discomfort into a perceptual and educational shift.
Initially, students were resistant to the naturally ventilated spaces, accustomed to air-conditioning. Yet within months, they adapted, enjoying the corridors and engaging with their environment. Projects like this show that with thoughtful sustainable design, architects can create spaces that reduce energy dependence, enhance comfort, and reconnect people with the rhythms of nature.
The Adaptive Comfort Theory
Traditional models of thermal comfort, like the PMV-PPD model by P.O. Fanger, assume comfort comes from maintaining fixed temperature and humidity levels, usually via air-conditioning. They treat comfort as a universal, physiological response, ignoring geography, lifestyle, and daily habits. In a country like India, with diverse climates and ways of living, these fixed thresholds often fail to reflect how people actually experience temperature.
The Adaptive Comfort Theory, developed by Prof. Michael Humphreys and Prof. J. Fergus Nicol in the 1970s, offers a more realistic approach. It recognises that people adjust physiologically, behaviourally, and psychologically — opening windows, changing clothing, or shifting routines — to achieve comfort across a wider temperature range. This theory aligns better with real human experience and with sustainable building design, yet it remains underutilised. Many large-scale projects still favour uniform, air-conditioned environments, overlooking regional context and occupant adaptability.
This gap between research and reality highlights the need to rethink how we define and design for comfort, especially in a climate-diverse country like India.
The Silent Heatwave
We have become so used to air-conditioning that we forget — air-conditioning doesn’t just cool the inside of buildings. It also heats up the world outside. The mechanism is simple; it takes heat from indoors and releases it outside. But in already warm urban environments, that extra heat adds up. In cities, this has been shown to raise night-time temperatures by as much as 2°C, creating a feedback loop where people crank up their ACs even more.
This cycle is especially dangerous in dense built-up areas where green cover is minimal. The more we rely on artificial cooling, the hotter our cities become and the more energy we use. It’s an invisible damage that worsens over time.
Of course, air-conditioning is sometimes essential. It helps manage thermal comfort during extreme heat. But our relationship with it needs a shift. Not just in how much we use it, but in how we think about comfort, resilience and design.
A Shift in the Mindset
If comfort is shaped by what we expect to feel, then maybe the first step is to question those expectations.
As sustainable architects in India, calibrating our own expectations as well as clients’ expectations about thermal comfort is necessary. If we keep chasing the idea of 22°C indoors, air-conditioning will always seem like the only answer. But if we adjust our thinking, accepting that in a tropical climate, comfort can exist between 24–28°C, new solutions begin to emerge.
Integrating passive design strategies and revisiting traditional methods of cooling like water coolers or khus coolers, or adopting mixed-mode ventilation, where mechanical cooling is supplemented by ceiling fans or natural ventilation through openable windows, for lowering indoor temperatures as much as possible. The good-old ceiling fans must become fashionable again! Many new companies are already doing a good job at it; now it’s time to align our aspirations.
True comfort isn’t something you can program into a thermostat—it’s something people experience, and redefining this comfort will require a shift in mindset, one where expectations and adaptability are as important as technical solutions. By embracing sustainable design strategies like natural ventilation, shading, and mixed-mode cooling, buildings can adapt to both the climate and the people who use them. As sustainable architects in Mumbai, SJK Architects see every project as an opportunity to design spaces where comfort feels natural, energy use is mindful, and the environment becomes a partner in well-being. When we trust both human adaptability and the rhythms of nature, we can finally design for feeling, not Fahrenheit.
Sparkrill International School, Warangal, Telangana; Designed by SJK Architects, 2009. Hotel at Bodhgaya, Bodhgaya, Bihar; Designed by SJK Architects, 2020
