Chilling with ceramics

All over Gujarat, in villages and towns and in between, I have seen concrete benches whose surfaces are covered with ceramic tiles or selected flat fragments of broken ceramic plates.

Fragments of ceramic tiling are also used to cover outer surfaces of buildings. A notable example is the curious Amdavad ni Gufa in Ahmedabad designed by architect BV Doshi.

Also, I have seen floors inside buildings covered with a mosaic of tiled fragments, rather than wood, clay, carpeting, or marble.

Why is ceramic tiling used so much in Gujarat. The answer is related to Gujarat’s usually hot climate. I am not a physicist, but the following seems to be the explanation. Ceramic tiles conduct heat well and dosperse heat rapidly from its point of contact.

A surface feels cool to the touch if heat flows from your body to it. The faster the heat is conducted from your body, the cooler the surface will feel.

Providing that the ambient temperature is below body temperature, ceramic tiles, unlike for example wood or carpet, will always feel cold to the touch. This is because heat flowing from the body to the cooler ceramics does so very rapidly in this material. The heat flows away quickly from the point of contact into the rest of the ceramic. In contrast, when you touch wood or cloth, heat will flow from your body to the material but will be dispersed away from the point of contact far slower than in ceramic. Therefore, touching wood or cloth gives rise to less of a sensation of cooling than touching ceramic.

Furthermore, covering buildings with ceramic as described above helps insulate their interiors from being warmed by the hot sun, which shines in Gujarat.

If my physics is faulty, please help me get it right by submitting a polite comment.

PS Metals have an even higher thermal conductivity than ceramics, but a far lower thermal capacity. This means that at any temperature, it will take far longer to warm a piece of ceramic than a similarly dimensioned piece of metal.