The imbrex and tegula (pl.: imbrices and tegulae) were overlapping roof tiles used in ancient Greek and Roman architecture as a waterproof and durable roof covering. They were made predominantly of fired clay, but also sometimes of marble, bronze or gilt. In Rome, they replaced wooden shingles, and were used on almost every type of structure, from humble outbuildings to grand temples and public facilities.
The tegula (Greek solenes) was a plain flat tile, or a flat tile with raised edges, which was laid flat upon the roof, while the imbrex (Greek kalupter) was a semi-cylindrical roofing tile, like a half-pipe, laid over the joints between the tegulae. When well-made and properly imbricated (overlapped), there was little need for further waterproofing or sealant.
The roofing area was generally surrounded by antefixae, which were often decorated and had several decorative anthemia to cover each end row imbrex.
The concept of imbrex and tegula roofing in pitched roof construction is still in use today as an international feature of style and design, and is the origin of the term imbrication for the condition of things arranged in overlapping layers.