Planning and Design

Planning and Design TIM, If a tile is not damaged by water, why do we need a waterproof- ing system installed under the tile in a shower? WHY SHOWER WATERPROOF- ING IS SO IMPORTANT Custom-tiled showers are a sizable investment and should last the lifetime of your home. Unfortunately, if you tear out shower tile as often as I do, you'll find a host of catastrophes, including horrifying mildew and mold growth as well as failed framing — rotted through after long-term exposure to water. The culprit often is misunderstood building science in a tile shower sys- tem. From a construction perspective, the function of a shower is to protect

the wood structure of the home by capturing water and directing it into the plumbing system. This principle, if mis- understood, can lead to inadequate or incomplete water-management systems installed under otherwise beautiful tile showers. When I meet with a homeowner experiencing tile shower issues, they are often surprised to learn that a tile shower has two parts. Part A is the waterproofing system, Part B is the tile surface — and just as importantly, one cannot function without the other. The trouble is that tile and grout are water-permeable, meaning they let water through to the substrate. Unfor- tunately, without a properly function- ing waterproofing layer, the substrate soaks up moisture, allowing water to pass through to the structural framing underneath, leading to decay, mold, and fungus, etc. Fortunately, a professional builder with a proper understanding of the tile shower system can prevent failures, and you and your family can enjoy your new tile shower for many worry-free decades to come. BG