In its design for the Sapphire 73-unit apartment building—its first residential project in Berlin—Studio Libeskind pursued both architectural and environmental goals. Located on a busy corner in the Mitte neighborhood, the building, with its large angular windows and canted, metallic-glazed tile walls, is a landmark in more ways than one.

The three-dimensional, geometric-patterned tile that clads the building is a key part of the firm’s investigation into sustainability and new technologies. Designed by Daniel Libeskind for Casalgrande Padana, the “Fractile” stoneware panels cover 27,986 square feet of the exterior. The tiles have a super-hydrophyllic titanium dioxide coating that breaks down organic deposits (dust and soot, greasy stains, and exhaust gasses) and non-organic stains (such as accumulations of sand or mud) when exposed to UV light, and sheds rainwater with great efficiency. Lab-tested under conditions that replicate 50 years of exposure to the elements, the self-cleaning, air-purifying cladding was specifically developed for façade use.