Rene Knip doesn’t care much for typographic conventions. As the founder of the Dutch studio Atelier Rene Knip, he makes typefaces carved from wood, soldered from iron, and painted onto ceramic tiles. Knip’s fonts live in the physical world, existing somewhere between sculpture and two-dimensional type. “I call it the second-and-a-half dimension,” he says.

Rene Knip designs for the Amsterdam Metro.

A few years ago, the Amsterdam Metro tasked Knip with modernizing its signage for 10 stations on the east end of the city, the designs for which are just now being installed. The stations’ existing wayfinding system was clear and legible, if slightly impersonal, with its sterile sans serif type. It was Knip’s job to make the Metro signage feel warm and more tactile, like a place where commuters feel at home.

Working in a new dimension comes with its quirks, though. With environmental type, architecture is the paper and a physical object is the ink. “The form of an alphabet is derived from the environment and the material,” he says. In the case of Amsterdam’s Metro, Knip and his team needed to craft the lettering from the glossy, white ceramic tiles that already lined the station’s walls and ceilings.

These tiles act like a physical grid that Knip uses to precisely position his boxy, oversized letters. The designers arranged the 10×30 centimeter tiles on a table and placed hand-drawn stencils over them to outline where each tile should be painted. They coded the tiles according to their graphical elements—full-painted tiles get one number, half-painted another, tiles with circular shapes another yet—which allowed factory workers to follow a paint by numbers-like guide when applying the cherry red pigment to nearly 20,000 tiles.

Knip’s typeface is modern yet folksy; the letters’ pixel-ish components are softened with rounded corners and the charmingly imperfect coloring that bears traces of the human hand. “If you look closely you can see the brushstrokes,” he says.

Typographers are often trained to design with surgeon-like precision, but Knip chose his medium for its less exacting qualities. In truth, he never meant to become a typographer in the first place. At one point Knip was studying to become a lawyer, but he realized that his real passion was art. He had a knack for sketching lettering and drawing calligraphy, which led him into type design, where he quickly learned that traditional typography wasn’t for him. “I wanted to have a more playful approach,” he says.

Designing environmental graphics allows him to abide by different rules. Clarity and readability are replaced with texture and scale. It’s less about legibility and more about materiality. To Knip, a successful environmental typeface can make a viewer feel something. “You can start to steer emotion much more,” he says.

Knip acknowledges that for all the differences between two and three-dimensional type, many of the basics remain constant. The capital letter A, for example, has some non-negotiable characteristics—two diagonal lines connected by a crossbar. It’s for good reason: You have to be able to read it. “The whole heritage of graphics design is 2-D,” he says. “It’s a sensibility that you cannot escape from.”

Most importantly, though, environmental typefaces, just like its ink or pixel-based counterpart, requires that the person designing it has a clear idea of how it’s going to be used. For Knip that means taking stock of his surroundings and asking himself questions, which are necessarily different than the questions someone fashioning a font for the computer would ask of herself. Instead of concerning himself with resolution and ink type, Knip finds himself wondering about if the rain will rust his letters or if the sun will glint off a material just right. Like architecture, Knip’s letterforms yield and bend to the world around them. “I consider the type design the final thing,” he says. “Never the beginning.”