When comparing tiles and porcelain in terms of waterproofing, porcelain is generally more waterproof. Porcelain tiles are known for their dense, non-porous surfaces, which make them highly resistant to water absorption. This characteristic is a result of the high firing temperatures used in porcelain tile manufacturing, which vitrifies the clay and feldspar, creating a hard, impermeable surface. According to the American Porcelain Tile Institute, porcelain tiles have water absorption rates of less than 0.5%, which is considered non-porous. In contrast, ceramic tiles, which are a type of tile, can have water absorption rates ranging from 3% to 7%, making them less waterproof. This difference in water absorption rates is due to the lower firing temperatures used in ceramic tile production, which results in a less dense, more porous material.