Restoration of cement and terracotta tiles has become a very popular practice over the past 10 - 15 years for both decorative/aesthetic and structural reasons.

Tiles, pointing, and bedding may become broken by storms, weathering, and by inexperienced people walking on them. In addition to mould, fungus, and lichen growth on tiles, these factors increase the potential for water damage caused by a leaking roof, possibly leading to structural failure, and unsightly interior staining of plaster walls and ceilings.

All roofing tiles become dirty with age and are subjected to mechanical and biological weathering caused by ultra-violet light, rain, wind, moss, lichen, and mould. The original coating on cement tiles also suffers from chemical breakdown due to atmospheric and local pollution which results in degradation of the tile surface and appearance due to discolouration, fading (oxidisation), and crazing of the coating surface glaze and coloured cement slurry.

After many years the coating on a cement tile can be completely weathered leaving little original colour and exposing the cement substrate of the tile. On older hand-made tiles the concrete surface can be substantially damaged after many years of weathering, ultimately requiring replacement.

Terracotta tiles can be covered in moss and lichen, completely changing the appearance of the roof. Moisture and salt damage can structurally weaken terracotta tiles, especially in coastal and high elevation areas. these factors can structurally damage tiles over a long period of time.

Mould, moss, and lichen also cause blockages in the water channels of the tiles. This can cause water leakage resulting in ceiling or structural damage if left unchecked.

Although a newer machine manufactured cement tile should not leak, even after the coloured surface weathers away, the resulting appearance due to colour loss, lichen and moss growth, and pollution build-up usually results in a very unsatisfactory visual appearance.