The writing is on the walls, but only when they get wet – that is when the secret messages or hidden designs appear in these seemingly innocuous concrete surfaces, like a durable and built-in version of Neverwet graffiti.

The project is called Silent Poetry and its creators, Frederik Molenschot & Susanne Happle, have started with a high-contrast approach: organic forms hidden in strict geometric slabs, but any other patterns are equally compatible with the approach.

The underlying magic-caliber, moisture-sparked trick works whether the material is drizzled on by the rain, doused in running water, touched by steam or impacted by condensation on a hot and humid day, making for innumerable creative possibilities both inside and outdoors.

Picture a public sidewalk, parking lot or city center on the one hand or a private walkway or concrete-tiled bathroom on the other. But also consider the range of applications from wayfinding in urban settings to domestic decorations on front decks or walkways that appear with the morning dew, using either modular precast tiles or larger poured-in-place slabs.

From the designers: “The possible applications of solid poetry are various: either at home in the bathroom, in the garden, in saunas and dance clubs, where the humidity is high or public spaces like bus stops or pavements. All forms of solid poetry have in common that they change the whole setting; they are surprising and have a life of their own.”