The mystery of Japanese Tiled Houses

I’m aware that this is a very niche post. Treat it as a little, disturbing glimpse into what I sometimes find interesting 😉

As I’ve mentioned before, the outsides of many buildings in Japan’s cities resemble the insides of bathrooms: the walls are covered by thousands of tiny, shiny ceramic tiles. I had noticed this phenomenon before, but always dismissed it as one of the many quirks of Japan’s modern architecture – like putting conspicuous Mickey Mouse ears wherever possible, or ending even the most perpendicular, simplistic tower blocks with oddly decorative finials. This year, however, I began to notice it more, and suddenly it was everywhere: if a building is not made of wood, it’s almost bound to be tiled. So I simply had to research it.

Turns out, this is not just a strange aesthetic choice, but a practical solution to a double problem that plagues Japanese cities: earthquake and harsh climate.

Earthquakes render brick buildings mostly unusable. In an earthquake, a brick house falls apart like a house of cards, burying everyone inside under a pile of clay cubes. Most of the existing brick buildings in Kyoto are listed municipal features, like the City Museum.

This gives you a choice of two other building materials: wood and concrete. Wood is expensive in maintenance, and doesn’t allow to build high, so unless you’re well-to-do townsperson wanting to have a villa, you’re left with concrete. Also, concrete trade is subsidized by the government, which makes the choice even more obvious.

However, raw concrete has two important disadvantages: one, unless you’re going for raw brutalism deliberately, it’s a damn ugly material: grey, drab, featureless. More importantly, it is not well suitable for Japan’s difficult climate. The immense humidity of the rainy season and the extreme heat of the late summer quickly erode raw concrete, eating through it like so much butter. Any un-clad concrete house in Kyoto is covered in vast damp patches and scars of acid erosion. This situation called for a drastic, innovative solution.

The Japanese realized that the conditions outside in the rainy months resemble closely those inside a used bathroom (as anyone who’s spent a summer in the semi-tropics can confirm). And what best protects the bathroom walls from erosion? Ceramic tiles!

Tiles, tiles everywhere
Tiles, tiles everywhere

And that’s the reason. Tiles protect concrete from the dampness. Concrete protects inhabitants from earthquakes. Both problems are endemic to Japan, and the solution is fairly ingenious; unfortunately for a place like Kyoto, the result is only minimally better, aesthetically, than leaving the raw concrete out (and often worse) – a price of compromise, I suppose.