Can new tiles go on top of the old ones?

Laying tiles over tiles sounds quicker and cleaner than a strip-outDemolitionKnocking down or stripping out whatever has to go before a renovation: walls, tiles, render, bathroom fittings, old floors or old insulation.. In some cases it can be done: when the old tiles are firmly stuck, flat and free of cracksCrackA 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., and their surface is prepared so the new tile adhesiveTile adhesiveA ready-mixed cement-based mortar, sold as a powder and mixed with water, used to stick tiles to walls and floors. It is spread with a notched trowel. can grip.

But a new tile is only as sound as the old one underneath. If some old tiles sound hollow when you tap them, or have already started to fall, they will take the new ones with them. In this bathroom, the dark old tiles had started to come loose on their own, so the only proper answer was to take them all out.

There are other limits too. With one layer on top of another, the floor gets higher, and the door, the drainFloor drainThe outlet in a floor where water drains away on roofs, balconies and in bathrooms, with a grate on top and usually a trap below. or the threshold may need adjusting. The old pipes stay inside the walls, and you can't move the fixtures or build a walk-in showerWalk-in showerA shower with no tray and no step, level with the rest of the bathroom floor. The water drains through a floor drain or a linear channel drain., which needs a new floor laid with a slopeFalls (drainage slope)The gentle slope built into flat roofs, balconies and bathroom floors so water runs to the drain or gutter instead of pooling..

In the bathroom with the green bathtub, the tiles, the tub and the old 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. came out down to the brick so the pipes could be replaced as well. If a bathroom only needs freshening up, sometimes the tiles can stay and the walls above them are repaired.

Whether your tiles can stay as a base is decided on site, by tapping them one by one and looking for leaks and damp.