Mar 27 2008 12:24PM | Permalink | Email this | Comments (1) |
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In previous blogs I’ve talked about the origin of mold as well as steps that can be taken during construction to keep moisture, and therefore mold, out of your home or building. In a nutshell, mold cannot grow without moisture, so steps that can be taken to reduce moisture’s entry into a building will go a long way toward reducing the chances of mold growth. As I pointed out in the last blog, it’s important that the various building trades working on the construction of a house work in concert. For example, when a roof intersects a wall, the trades must coordinate to make sure this valley is properly flashed and the water resistant barrier drains onto, not behind, the flashing before the roof and clapboard or other siding materials are installed.

In this blog I want to talk about the use of mold resistant products. They represent an improvement in building materials and there are many excellent choices. My company, USG Corporation, manufactures Sheetrock Mold Tough gypsum board and other products which should be used in wet areas where higher moisture contents are likely to occur. These include kitchens, bathrooms and basements. The key issue, however, is that mold resistant products are no substitute for good design, good building practices and good maintenance.

Any mold resistant product will eventually fail if continually exposed to moisture intrusion. Keeping water out of buildings is not overly complicated but it can be time consuming. It’s a matter of paying attention to the details during the design, construction and maintenance of your home or building. For example, architectural designs should always provide a clear path for water to drain off the roof and away from the building. Overly complicated roof designs can result in bottlenecks where the water can overwhelm the flashing and drainage details and does not have a clear path off the building. During construction, building materials should be kept dry. In maintaining your home, keep an eye out for moisture—a damp gypsum wall panel or a pool of water in the basement needs to be investigated and corrected.

In simplest terms, you want to answer two questions: 1) where can/does the water come from?; and 2) where can/does the water go—how can it get out? If you always keep these two questions in mind, you’ll be miles ahead in solving mold problems. Let’s look at two areas of the home where moisture is always a concern: bathrooms and kitchens. These are rooms in which Sheetrock Mold Tough gypsum board should be used. I would also draw the distinction, however, that other products such as USG’s Fiberock Aqua Tough Panels or Durock Cement Board should be used as the tile backer for tub and shower enclosures. Showering habits can vary enormously—some people take five minute showers, while others may be in the shower for 20 minutes. Water will seep through tile grout and that’s OK as long as the wallboard behind the shower is designed for repeated moisture exposure and the water has a path to drain back into the tub.

For the rest of the room, our Mold Tough product is recommended. Why? Because you never know how much moisture will come in contact with the gypsum wall board. Hot, steamy showers can lead to a heavy moisture residue which may soak down to the gypsum board—where a mold resistant product would be ideal. This “belt and suspenders” approach of preventing moisture and yet providing a buffer for occasional wetting episodes, will help you keep moisture and mold at bay. Again, mold resistant products alone cannot compensate for poorly designed or improperly installed plumbing or bath details.

So when do you use mold resistant products and how should they be integrated into the rest of the room? Let me give you a driving analogy. When you leave your home or office you put on your seat belt—not because you expect to have an accident, but because you may have an accident. And to take the analogy one step further, you don’t drive recklessly and hope that your seat belt or air bags will save you. You drive prudently but you are prepared in the case of an accident.

The same is true with mold resistant wallboard. While you don’t expect a major moisture intrusion, it could happen. And you don’t design, build or maintain your building in a haphazard manner and hope that your mold resistant products will bail you out when trouble strikes. You use mold resistant products where it is appropriate—in bathrooms, kitchens and basements—but you rely on the integrity of your building to first and foremost keep moisture out.

In my next blog, I plan to talk about moisture issues in finished basements.