The term “mud job “is a technique that has been used for countless years to ensure that a tile installation is installed on a permanent, stable and rigid sub-base. A “mud job “is basically a layer of mud, which is a combination of sand and cement, that is installed as the sub-base for the new tile installation. Most mud is comprised of one part cement and three parts sand, and is installed extremely dry. A good tile installer will minimize the water used to mix the sand and cement. The lower the water content, the stronger the sub-base for the tile will be. As in all masonry application, the less water the stronger the resultant masonry product. This is consistent in concrete, water content is a critical characteristic of concrete, and its control is inherent to a strong and professional masonry product.
The use of mud under your tile installation will provide the best, and most resilient tile installation possible, however the cost will be more than a conventional thin set application, and the time to install the entire system will take a longer. In addition, special planning must be done, to provide the room for the proper depth of mud bed, under your finished tile surface. If the mud bed is a three inch bed, then either the structural framing under the area to be tiled must be dropped to accommodate the additional three inches, or all the adjacent floors must be raised to accommodate this mud application.
The use of mud, for tile installations, is a sign of a professional and experienced tile contractor. Years ago, this was the only method of tile installation, due to the fact that thin set mortar and adhesives had not been developed.