Today, Tub and Shower enclosures can be wonderfully decorated with all sorts of attractive wall tiles. Although a large variety of coverings can be easily purchased such as fiberglass and acrylic panels, ceramic tiles and natural stone tiles are most used today. Most enclosures that I normally inspect make use of either ceramic tiles or a plastic/acrylic wall coverings.
During normal showering, water is sprayed on the ceramic tiles or some other water-proofed material. If the shower wall is well maintained, the water is directed down the wall and into the drain. Typical maintenance consists of routine grouting and caulking and sealing the inside enclosure corners with a waterproof caulking. The exterior areas where the tub connects to the tiles will also need to be sealed or caulked.
However when small cracks or unsealed grout joints in the ceramic tile surfaces develop, usually with the passage of time, water may have a tendency to penetrate behind the tiles through deficient grout joints and cracks. Leaks that are allowed to persist without repair can often lead to deterioration of the wall under the tiles and also permit damp areas where mold will grow. I have seen, much to my amazement, drywall that has been painted over, but would consider this to be inadequate and an installation defect.
That’s why it’s so important to have an approved substrate material installed under the tiles. If a small leak is unnoticed or left unrepaired, the wall behind the tiles can become rotted and will have to be replaced. Than double the work. And the leak may extend to a ceiling of another room.
Contractors in the past have installed waterproof drywall or green board in the bathroom areas and in the showering enclosure which was considered adequate. Today construction procedures mandate the use of a much better material: a concrete substrate panel that can easily withstand water penetration, called “wonderboard” or similar product. This cement panel board is usually screwed into place and than tapped at the joints where the panels meet together, providing a water tight surface. Water cannot penetrate or deteriorate this panel, because it’s made of concrete.