The battle against mold in the home has recently entered a new phase. Driven by a growing knowledge among homeowners of the damage mold can cause, as well as by an increasing number of residential mold-related lawsuits, the homebuilding industry has stepped up its efforts to combat mold.

Manufacturers in particular are developing new building products and materials that are specifically designed to inhibit mold proliferation. When combined with preventive strategies, these products can help make your home a healthier place to live.

Mold is a concern for all homeowners, no matter where they live. In fact, according to a recent study, homes in dry climates such as Nevada and Arizona are just as susceptible to mold as those located in humid climates. Common strains of household mold, such as Aspergillus versicolor, Aspergillus niger and Stachybotrys chartarum, can be found everywhere, indoors and out. And when provided with warmth, moisture and food (which can be anything from paper to leather to dust in ductwork), mold can reproduce rapidly.

Ironically, mold is more of an issue in today's modern homes because, in the quest for improved energy efficiency, houses are more airtight and less able to "breathe." And when it comes to kitchens and bathrooms, mold can be a particular problem because those areas tend to have higher humidity levels that can be compounded by inadequate ventilation.

Not only is mold unsightly and a potential health risk, especially for individuals with severe allergies or asthma, but it can also damage the integrity of residential structures. Many building materials contain starches, organic adhesives and cellulose sugars that provide a veritable smorgasbord for the fungus. If mold growth becomes too prevalent in structural materials, especially in floors and ceilings, it can cause sagging and even affect a structure's ability to bear loads.

The good news is that there's an ever-expanding list of mold-resistant building products on the market today, particularly for use in kitchens and baths.

Waterproofing Walls

One of the most common mold-related mistakes made in modern bathrooms is installing ceramic tile over paper-covered gypsum wallboard, says McGregor Pearce, an environmental health consultant based in St. Paul, Minn. The paper and moisture in the wallboard provide a perfect breeding ground for mold, but it's difficult to detect mold growth behind ceramic tiles until it has done a lot of damage.

Manufacturers have addressed this problem by creating new wall panels that resist mold. For instance, DensShield wall paneling from Georgia-Pacific was designed specifically as a tile backer for walls, ceilings and floors with ceramic tile installations. Light and easy to install, DensShield has a glass-mat facing and an acrylic coating that acts as a moisture barrier, eliminating one of the elements that promotes the growth of mold in wallboard. DensShield is recommended for use in wet areas such as around showers and tubs.

A similar product, called DensArmor, is an interior drywall panel that also uses glass mats instead of paper on its surface to prevent moisture infiltration, making it a good alternative for use in damp areas such as bathrooms and basements. For a completely paperless application, the company recommends using fiberglass mesh tape and a setting-type compound to bed the tape.

Another backerboard for use in bathrooms and kitchens is Hardiebacker cement board from James Hardie. A mold-resistant substitute for drywall, Hardiebacker can be used on walls, ceilings, floors and countertops. Rather than a glass mat or mesh, Hardiebacker incorporates a lightweight cement formulation and Moldblock Technology to create a strong, durable and moisture-resistant board.

Using a waterproofing membrane such as Protecto Wrap's AFM-WM Waterproofing Membrane, designed for use on floors under tile or stone, can stop the moisture that causes mold. "More and more people today are realizing that what you don't see [such as unseen mold in walls or substrates] can indeed harm you," says Melissa Lucas, marketing coordinator for the Denver, Colo., company. "Therefore, it is crucial to use these types of preventative measures, such as waterproofing membranes. If installed correctly, these products will last the lifetime of the house."

If you are adding or replacing a ceramic tile shower, consider using a waterproof and vapor-tight membrane and drain system such as the Schluter Shower System. The all-inclusive package consists of a number of components, including a waterproofing membrane, a prefabricated shower tray, a shower curb and a floor drain with an integrated bonding flange. The system is designed to enable the use of standard drywall instead of cement board or other specialized tile backers when installing tiled showers, according to the German company, whose U.S. office is in Plattsburgh, N.Y.

Anti-Mold Additives

A relatively simple way to improve the mold-resistance abilities of certain products is to add Microban, an anti-bacterial chemical compound that can be incorporated into building products to provide continuous protection against microbes and prevent the growth of mold, mildew and bacteria. Microban is used in products ranging from bath lavatories (sinks), tubs and vanity tops to flooring, wall coverings, exhaust fans, windows, doors, countertops and kitchen sinks, as well as adhesives, caulks and sealants.

Anti-microbial additives are even used in that essential bathroom item: the toilet. Foremost Groups of East Hanover, N.J., is planning to introduce a line of toilet seats with Microban to prevent the growth of mold and inhibit resulting odors and stains.

Microban also has been added to paints, such as Kitchen & Bath Enamel from California Paints, Super Acro from Miller Paint Co., Platinum Ceramic from Hirshfield's Paints, MicroSpec from O'Leary Paints and Solace from Davis Paint.

Other companies have developed their own antimicrobial additives. Sherwin-Williams' Duration Home Interior Latex and Harmony Interior Latex paints not only have antimicrobial properties that inhibit the growth of mold on the paint film but also have earned the GreenSure designation, which indicates the paints emit little or no volatile organic compounds (VOCs) that can affect indoor air quality.

EnviroCare of Wilmington, Mass., offers an entire line of mold-fighting products. The company's Moldex Paint is mold-resistant, while its Moldex non-corrosive cleaner is an EPA-registered disinfectant, sanitizer and cleaner designed specifically for mold remediation and flood damage restoration projects. EnviroCare's ForSite goes one step farther, providing a permanent, mold-resistant protective coating and sealer suitable for use on wood, concrete, tile, gypsum and other surfaces.

Mold-Resistant Insulation

An increase in the cost of home energy has caused many homeowners to examine the insulation in their walls and attics. Insulation not only prevents exterior air from infiltrating a home and conditioned interior air from escaping, but also can help reduce mold proliferation on outside walls, since condensation tends to occur when warm, moisture-laden air comes into contact with cold walls.

ProPink fiberglass insulation batts, from Toledo, Ohio-based Owens Corning, also are designed to assist with vapor control in the walls of the home. The insulation is available in R-13, R-15, R19 and R-21 ratings.

Controlling Moisture

Given mold's need for moisture, addressing water leaks (both inside and outside the home) and dampness is a wise move for homeowners. To keep the indoor humidity level between 30 to 60 percent, homeowners should ensure that there is adequate insulation around windows, pipes, roofing and floors, according to the Responsible Solutions to Mold Coalition (RSMC), an industry group that promotes effective methods for combating mold in residential and commercial construction. The RSMC also recommends the use of a dehumidifier in areas prone to dampness.

In addition, ventilation fans that remove moist air from bathrooms, kitchens and laundry rooms are essential. Ideally, the bathroom fan should run at least 20 minutes after showering or bathing. Some ventilation fans, such as the Panasonic WhisperGreen, include a variable speed control and a delay timer, while Broan's SensAire model has a humidity sensor and motion sensor control for user-friendly operation.

As for those state building codes that do not require an exhaust fan in bathrooms with an operable window, Pearce believes they are "a ridiculous exemption from best practice. The bather is unlikely to open a window in the middle of a Minnesota winter. In any case, a ventilation fan is much more effective in removing moisture than a passive open window."

Keeping your home clean and clutter-free can also reduce the chance for mold growth, especially in those areas where dampness is an issue, notes the National Association of Home Builders (NAHB). Vacuum regularly, use area rugs or washable surfaces instead of wall-to-wall carpeting in areas susceptible to moisture, and keep paper, books, clothes and other possible sources of food for mold out of the humid or damp areas of your home.

And don't forget to check outdoors. Make sure downspouts and gutters are clear of debris that can block the flow of water from the roof. Ensure that rainwater from the downspout flows away from your foundation. Use splash blocks or downspout extenders if necessary. By following these simple strategies, and using mold-resistant building materials wherever possible, you can stop mold in its tracks.