Designing Cooler Cities: Research for Heat Resilience and Better Urban Living

How do people experience heat in urban spaces – and how can buildings, streets and public spaces be designed to remain liveable in a changing climate? In his doctoral research, Ben Gottkehaskamp connects architecture, climate simulation, human physiology and software development. In this interview, the guest researcher and lecturer at the Chair of Building Technology and Climate Responsive Design of Prof. Thomas Auer talks about outdoor thermal comfort, sustainable urban planning, and why simulations always require critical thinking.

What is the topic of your research? 

My research focuses on the relationship between the built environment and human physiology–more specifically, on outdoor thermal comfort. I want to understand how people respond to different outdoor conditions, both physiologically and in terms of how comfortable or uncomfortable they feel. 

Many existing comfort metrics provide a single value for a standard person, for example indicating “strong heat stress”. But people are different: children, older adults and young adults may all react differently to heat. My goal is therefore to develop a new metric or expand existing ones so that they better reflect these differences. 

I aim to combine environmental data, local climate conditions and in future physiological responses in my pre-studies. During so-called thermal walks, we can collect information about vegetation, buildings, shading, air temperature, wind, thermal radiation and bodily responses such as skin temperature, heart rate or sweat rate.

What have you learned so far, and what impact do you hope your research will have? 

I am still at an early stage of my forthcoming doctorate, but I have already gained a strong understanding of why a human-centred approach is so important. Thermoregulation models can help represent the human body in simulations, ranging from very simple abstractions to complex multi-segment models that simulate different parts of the body separately. The challenge is to find the right level of abstraction: detailed enough to be meaningful, but not so complex that the required input data becomes unrealistic to collect. 

In the long term, I hope my research can provide useful data and contribute to a practical comfort metric. Instead of producing just one value, such a metric could describe a range: when does a situation become uncomfortable for certain groups of people, and when might it become dangerous? These insights could eventually inform standards, urban planning and large-scale simulations, helping planners make more sustainable and evidence-based decisions. 

How will climate change affect cities and rural areas? 

Cities will experience more hot days and warm nights. The urban heat island effect intensifies this problem: sealed surfaces, dense buildings and limited vegetation store heat during the day and release it slowly at night. This can be particularly dangerous for vulnerable groups, including older people, children and people with pre-existing health conditions. 

In rural areas, the situation is different. Green spaces and water bodies often provide natural cooling, but other risks are increasing, such as drought, water scarcity and crop failures. Overall, our climate conditions are changing noticeably, and we are not yet sufficiently prepared for extreme heat. 

What makes housing more heat-resilient, and what improves quality of life? 

Passive strategies are essential. We should not rely too heavily on air conditioning, as it consumes energy and can further contribute to climate change. As regards buildings, effective measures include external shading, good insulation, thermal mass, night-time ventilation, and bright, reflective surfaces. 

At the urban level, vegetation plays a major role. Street trees, parks, green roofs and green façades provide shade and cool the environment through evapotranspiration. Initiatives such as Baumentscheid München campaign for more street trees, more shade and a continuous green network across the city. Water features and well-planned ventilation corridors are also important passive strategies. 

Improving quality of life means reducing heat stress in outdoor spaces while better understanding how different people experience heat. This is where I see the relevance of my own research: if we know when conditions become critical for specific groups, planners can decide more precisely where shading, greenery or other interventions are most urgently needed. 

You also teach. What do you pass on to Master’s students in Resource Efficient and Sustainable Building? 

I teach Advanced Modeling, a course on thermal simulations in which students work with Transient System Simulation Tools such as TRNSYS. The aim is not to use simulation merely as a validation tool, but as an exploratory method. Students learn how to build models, make meaningful abstractions, test design ideas and combine different strategies. A key focus is critical thinking: simulation results should never be trusted blindly. A model is only as good as its assumptions. I want students to learn how to think like climate engineers–analytically, interdisciplinarily and responsibly. 

How did you become a software engineer and climate engineer? 

During my architecture studies, I was already strongly interested in simulation and sustainability, and thermal building simulations bring these topics together very well. That is why I chose to pursue the Master’s program in Resource-efficient and Sustainable Building at TUM. During a year abroad at the National University of Singapore, I focused intensively on climate models, thermal walks and outdoor comfort. There, I was also involved in a project that monitored the campus microclimate in order to mitigate urban heat. In my current role as a software developer, I develop tools and work on new solutions. I bring both of these experiences together in my projected doctoral research.