Favourite books: you can’t measure delight in kilowatt hours

This is a gem of a book, which I first read when I was doing a Masters in Environmental Design. I’ve re-read it a few times since and recommend it liberally!

Thermal Delight in Architecture is in the same vein as In Praise of Shadows by Junichiro Tanizaki, in that it is a commentary situated at the poetic confluence of cultural, spiritual, sensory and practical experiences of space. Where In Praise of Shadows focuses on light, this book is about the thermal environment. It is a very short book, but it gently reveals – and can easily be digested in a few short hours.

In our earnest and necessary endeavours to respond to the climate crisis, we seem to have reduced the thermal environment to quantitative and technical metrics of energy efficiency and insulation. Important as those things are, you can’t measure delight in kilowatt hours.

That’s why I like this book. None of it is particularly new or unknown, but it always makes me smile. The revelation is in how unconscious we are of the way our thermal environment affects us – physically, emotionally, socially. It is so intrinsic to our being and our behaviour that it often isn’t mentioned. We spend endless time discussing the weather, but when we cross the threshold to the internal environment, it is largely sanitised or forgotten, beyond exclamations of annoyance at draughty air conditioning or the stuffiness of a teenager’s bedroom…

You could argue that all senses affect the body – sound causes your ear to vibrate, touch causes your skin to indent. But these are subtle changes from which our brains draw wider conclusions. Heat and coolth, however, elicit a much more visceral response, having an impact on our whole body through the skin – our largest organ.

When you see something red, you don’t become red. But when you feel something hot, you absorb its heat. You become it.

Our thermal sense is arguably the primary, most immediate medium through which we experience space. But in talking about the design of buildings, it is barely mentioned or considered in anything other than a practical sense to achieve some kind of flawed notional ‘norm’ of basic comfort standards – something this book guards against. The analogy goes that if you were to attach yourself to a drip for all your calorific needs, you would have all the nutrients to live, but you would never again experience the feeling of hunger before tucking into a roast dinner. It would be a sad scenario. And yet that’s how we often design our thermal environment. Air conditioning is set to calibrated ‘norms’, when most people want to be able to open a window, experience the contrast of cool and cosiness as and when they choose and in a nuanced way, depending where they are, who they are with and what they are doing.

The book describes beautiful, often familiar thermal archetypes such as the hearth (radiant, directional heat with warm front, contrasting cold back), a warm bath (steam and relaxation), a lush, tropical garden (humidity), and the evening Mediterranean piazza (walking over radiant warm stone). Then there’s the experience of huge contrast, such as jumping into snow after a Finnish sauna or hot cocoa on a cold day; the shade of a tree on a hot afternoon. But we rarely explore how these principles can be applied to the buildings we design and inhabit on a day-to-day basis.

This book was a gentle eye-opener to the transformative possibilities of designing explicitly for cosiness and coolth, playing with an understanding of radiant or conductive surfaces. In our work, we become quite obsessed with the sensory experience of the spaces that we create, exploring microclimates and surfaces that are sensorily rich and exhilarating.

The essence of the ideas in this tiny little book have influenced the work of our practice in all kinds of ways: We’ve been building with straw to create space that feels thermally and acoustically like you’re wrapped in a duvet. The deep reveals of the curved straw bales allow us to create window seats that are really special on a sunny day, or even a rainy one. We recently built a museum with an atrium courtyard between new and old structures. The masonry walls really capture the sun and give a sense of warmth long into the evening, with a bakery oven at the heart of the museum, giving out that warm scent of baked bread in the heart of the building.

I’m constantly baffled as to why this barely gets talked about, not least because it is such a rich seam of design inspiration. As our climate changes, we need to find the beauty in our relationship to heat and coolth, humidity and aridity, stillness and breeze… because only by loving it, will we protect it.

As told to Pamela Buxton

Katy Marks is founder of Citizens Design Bureau

Thermal Delight in Architecture, Lisa Heschong, MIT Press, 1979

Read more on books and see what books Conrad Koslowsky and Geoff Shearcroft picked