Tile adhesive

Tiles used to be bedded on a thick layer of sand and cement mortar. Today tile adhesive is used almost every time: a ready-made mortar with additives that give it a strong grip. It is spread in a thin layer and combed with a notched trowel so the tile beds down and bonds over its whole back.

Not all adhesives are the same. Large or porcelain tiles, outdoor areas, roof terracesFlat roof (roof terrace)The flat concrete roof on top of a building. It is the most common kind of roof in Greece and the part that takes the most sun and rain. and balconies that bake in the sun, and floors with underfloor heating need more flexible, stronger adhesives. The base has to be sound, clean and flat, and on fresh renderRender (plaster)A layer of mortar (sand, cement or lime, and water) spread over brick or concrete to give a wall a straight, sound surface ready for paint or tiles. the surface is often scored so the adhesive grips better.

If a tile sounds hollow when you tap it, the adhesive usually did not cover its whole back. Tiles like that crackCrackA split or gap in render, concrete, a wall, a coating or wood. Fine cracks are usually only on the surface; ones that grow, keep reopening or run diagonally need attention. more easily and, on terraces and balconies, let water collect underneath. When old tiles are stripped out, the leftover adhesive is removed before any new layer goes on.