In the US, a tile's slip resistance is measured by its wet Dynamic Coefficient of Friction (DCOF) per ANSI A326.3, with 0.42 established as the minimum threshold for level interior floors that are expected to get wet. However, standard DCOF ratings do not explicitly cover sloped shower floors, ramps, or pool decks. In those spaces, physical factors like grout joint frequency, tile size, surface texture, and manufacturer product-use declarations provide better practical safety than a single spec number. Before purchasing, review the manufacturer’s technical spec sheet and order physical samples to test the tile's finish in person.

The PEI rating (ASTM C1027) measures how well a glazed tile's surface resists visible wear from foot traffic; it does not indicate tile strength, water absorption, or slip resistance. Most residential floors perform reliably at Class III, while heavy-traffic areas that collect outdoor grit, such as kitchens, entryways, and hallways, are best suited for Class IV. Higher ratings, such as Class V, are engineered for commercial environments and are rarely necessary for home use. Because PEI only applies to glazed surfaces, unglazed porcelain and natural stone will not feature a PEI class. Once you narrow down the technical rating on a spec sheet, order a physical sample to test how the finish and shade look under your room's specific lighting.

A tile shower can last 40 to 80 years or more, far longer than any prefabricated unit, but grout and caulk age on their own schedule. This guide breaks down what actually fails first, how long each component really lasts, and what to do to keep your shower looking new for decades.