How, where, and why mold grows in our homes, and what to do about it.

(Left) Dr. Lisa Nagy has built an environmental medicine practice treating mold-related illnesses on the Island. Photo by Lynn Christoffers (Right) Doug Gordon brought XSpor technology to the Island after witnessing its effectiveness in combating mold at his father's Connecticut home. Photo by David Welch

You know the odor. It’s that musty, dank, damp, earthy, and altogether unpleasant smell that’s immediately recognizable. Call it mold or mildew, it’s not good news and it’s growing everywhere around us on the Island – in basements, crawl spaces, attics, on clothing, shoes, and furniture.

Our homes and cars are susceptible to mold growth for a variety of reasons, but no matter what the cause, mold can lead to both illness and compromised real estate values.

Over the years, I’ve rented houses and stayed in hotel rooms that nearly knocked me out with noxious fumes or gave me bad dreams after seeing pink and brown slime growing on the plastic shower curtain liner. I’m embarrassed to admit that I unknowingly cultivated a crop of fungi on a pair of my favorite fine leather shoes in my own bedroom closet – without any noticeable musty smell to be found anywhere. Years ago, I opened a drawer in an old pine dresser I’d stored in my basement only to find its contents – treasured family photos and papers – to be damp and stinky. I spent the next three days in bed, overcome by flu-like symptoms, coughing, sneezing, headache and exhausted. And, when I was house hunting here, my real estate broker knew me well enough that if she opened the front door to a house we were about to tour and was greeted by “the smell,” we exchanged “the look” and simply backed away.

The subject of mold seems to come up more often these days. Is it becoming more plentiful or are we simply becoming more aware? Since Hurricane Katrina made landfall on August 29, 2005, and devastated New Orleans and much of the surrounding region, our personal radar about mold has grown more sensitive. Who can forget the images of all the flooded, condemned homes with toxic black mold creeping up the walls?

Here’s a fresh look at a stinky situation – what you should know about mold in your own backyard (and probably your basement, too).

What are mold and mildew?

Mold is a type of fungi that grows in the natural environment. Tiny particles are indoors and out, thriving on moisture and high humidity levels, the very conditions we often experience here on the Vineyard, especially in the summer.

Mildew is a type of fungi as well and is referred to as a kind of mold or mold in its early stages. It can be downy or powdery. Downy mildew appears as yellow spots that become brighter, then turn brown. Powdery mildew is whitish, turning yellowish-brown before becoming black. Mold has a fuzzy appearance and can be orange, green, black, brown, pink, or purple in color.

Mold produces spores — microscopic cells that spread through the air, by water or insects, acting like seeds, creating new mold colonies when they land in just the right setting.

How can mold affect our health?

The most commonly reported health problems from exposure to mold are respiratory in nature – sneezing, stuffiness, coughing, wheezing, and throat irritation. Rashes and eye irritation are also typical reactions for those who are sensitive to mold. People with actual mold allergies may have more severe reactions, including shortness of breath, and more vulnerable populations – those with immune system problems and the elderly – may be more likely to get serious infections in their lungs. One local physician, Dr. Lisa Nagy, has built an environmental medicine practice treating what she believes are mold-related illnesses after experiencing debilitating symptoms herself that she links to mold exposure in a former home off-Island.

Why is the Vineyard so conducive to mold?

According to Phil Regan, principal at Hutker Architects in Vineyard Haven, we experience a wide range of climatic conditions that can lead to moisture intrusion in our homes. The warmer seasons’ low-lying fog can enter through an open window, condensation can occur on interior basement foundation walls, and heated indoor temperatures differ dramatically from outdoor temperatures. “They can all result in mold,” he says. “Homes have always had mildew and mold issues, and poor building practices can be most responsible for mold development.”

Tim Boland, executive director of Polly Hill Arboretum, blames our abundance of atmospheric moisture for the overpopulation of mold on the Island as well. He cites close proximity of plantings to building foundations as another culprit.

Why do some homes seem so much moldier than others?

Brian Nelson, a principal and mechanical engineer at Nelson Mechanical Design in Edgartown, specializes in installing all types of climate control systems in homes and businesses across the Island. The company started off dealing primarily with plumbing issues, but, according to Mr. Nelson, controlling mold from an engineering perspective has become a huge part of their work. “If we can control temperature and humidity, we can control mold,” he says.

Experts agree that mold’s needs are simple: food (such as sheetrock, wood, or fabric), a suitable place to grow, and moisture. Even dust that settles in the right place can provide a steady diet.

Mold can enter your home through open doors, windows, vents, and heating and air conditioning systems. Airborne mold can also be conveniently carried indoors by piggybacking on clothing, shoes, bags, and pets. It flourishes almost anywhere that provides sufficient moisture or humidity.

According to Andy Provitola, principal and consultant at Environmental Resources, a company headquartered in Norwell that provides mold testing and assessment on the Island, controlling humidity is key. “Seventy to 90 percent humidity makes mold grow,” he says. “Everyone should have dehumidifiers. Keep windows closed if it’s above 80 percent humidity outside and crack windows at night if the humidity decreases. Central air conditioning or window units are a huge help.”

Mr. Nelson suggests that relative humidity of between 40 percent and 60 percent indoors is the healthy range. “Below 40 percent and you can have respiratory issues from dryness,” he says. “But above 60 percent is conducive to mold.”

Mold thrives in houses where leaks, floods, poor ventilation, humidity, and other sources of moisture have been left unattended. The key to preventing its growth is, according to Mr. Provitola, to deal with any water issue within 24 to 48 hours from occurrence.

Surprisingly, even newer houses built with state of the art technology can be prone to mold. Mr. Nelson explains: “The push toward making buildings tighter and more energy efficient means houses don’t breathe. The systems have to work in tandem to seal the home and treat the air. Once a home is sealed you have to ventilate it to remove moisture.”

How can you prevent mold in your home?

The best way to deal with mold in the home is to prevent it from getting out of control. There is always some mold everywhere but there are ways to keep it from becoming a problem:

Clean and dry out your home thoroughly and quickly (within 24 to 48 hours) after water infiltration from leak or flood.

Keep humidity levels as low as you can – 50 percent is ideal – all day long. Window air conditioners, central air conditioning, and dehumidifiers in the dampest locations will help keep the air dry.

Be sure your home has adequate ventilation. Use exhaust fans that vent outside from the kitchen, bathroom, and laundry room.

Don’t carpet bathrooms or basements and use mold-killing products to clean bathrooms.

Add mold inhibitors to paints.

Maintain your home by keeping roofs, walls, windows, and plumbing in working order.

Keep landscape plantings six to eight feet from your home’s foundation to allow sunlight and air movement, both of which help prevent mold.

If you have a crawl space, install a vapor barrier between the ground and the floor above.

Keep downspouts and irrigation systems moving water away from your house.

If building a new home or remodeling, consult with experts to ensure that new materials and technologies are implemented correctly to prevent moisture from building up.

Site any new construction to take advantage of air and light, encouraging prevailing summer breezes and discouraging prevailing winter breezes.

How should I deal with a current mold problem?

If you detect the odor of mold or see evidence of mold or mildew in your home, there are several ways to approach the problem. First, a home inspector who has received training in mold can come to verify your suspicions. Mr. Provitola, the certified mold assessor, suggests that homeowners be wary of contractors who profit from “detecting” mold.

“Get an independent professional viewpoint from someone who doesn’t do remediation or repairs,” he advises. “There’s a lot of bait and switch out there and no regulation in the industry.” He also recommends relying on visual inspection. “If you see it, you know it’s there.” His company uses a variety of diagnostic tools – visual observation, air sampling, and infrared moisture mapping – depending upon the situation, and provides a detailed written report and interpretation. In the last eight years, Mr. Provitola has conducted more than 3,000 mold assessments at the request of homeowners, buyers, sellers, real estate agents, and physicians whose clients suspect they are suffering from mold-related illnesses.

A new company on the Island, XSpor Life Sciences, now offers a mold clean-up treatment that, according to Doug Gordon, principal, can last up to two years. XSpor, a Connecticut-based firm with licensees across the country, promises that its proprietary plant enzyme-based spray, administered by a trained employee, digests mold spores, eliminating mold both on surfaces, and inside wall cavities.

A carpenter by trade, Mr. Gordon has experienced mold issues firsthand. He says that he witnessed the success of an XSpor treatment on his father’s Connecticut home and that it convinced him to bring the technology to the Island. He has since treated a multitude of clients’ homes with a 100 percent satisfaction rate. In fact, he says, he does not accept payment unless a homeowner is pleased with the outcome.

“In the past 30 years on the Island, I’ve torn out sheetrock, used bleach and water, reinsulated, re-sheetrocked, and painted a variety of properties in an effort to get rid of mold from customers’ houses,” Mr. Gordon explains. “XSpor eliminates the need to do that.”

He says that the product is a formulation of enzymes scientifically engineered to kill mold. Applied in mist form, it is organic and, according to the company’s website, has been verified as safe for humans, pets, and plants. Occupants must leave the house for at least a full day, Mr. Gordon says, and up to 48 hours is recommended. There is little residue after the treatment and a pleasant citrus scent remains. The company markets its service as a cutting-edge solution that ensures a mold-free environment without demolition of mold-infested areas or harsh chemicals.

The Centers for Disease Control and Prevention does not recommend routine sampling for molds. According to its website, “If you can see or smell mold, a health risk may be present. You do not need to know the type of mold growing in your home. No matter what type of mold is present, you should remove it.” Instead, they recommend removing the mold and preventing further growth, providing guidelines for safely using bleach as a cleaning agent. If the area affected is greater than 10 square feet, they suggest consulting the U.S. Environmental Protection Agency (EPA) guide titled “Mold Remediation in Schools and Commercial Buildings.” Although its focus is not on homes, the document pertains to other building types as well. It is available online at the EPA website under mold remediation.

If you choose to clean up mold in your home, here are several recommendations:

Do not attempt to clean up mold if you have any symptoms of illness or allergies.

Small areas of mold can be cleaned with detergent and water or a mildew and mold cleaner.

Wear gloves and goggles during clean-up.

Discard any sponges or rags you use.

If the mold returns quickly or spreads you probably have a water leak or another ongoing moisture problem. Be sure you’ve searched for underlying causes before attempting clean-up.

Bleach or other disinfectants may be needed on surfaces after mold removal if occupants are thought to be susceptible to fungal infections. Follow the label instructions carefully if you use chemical cleaning agents.

If the mold damage in your home is extensive, there are professional mold remediation specialists both on the Island and on the mainland that can help. Make sure that the contractor has a verifiable track record, check references and be certain that they adhere to guidelines established by the EPA, the American Conference of Governmental Industrial Hygienists (ACGIH), or other professional or government organizations.

What can mold do to my property value?

According to Lisa Stewart, owner/principal broker at Lighthouse Properties in Oak Bluffs, houses that smell of mold or mildew are “a huge turnoff.”

“Even a whiff of mildew is a turn-off,” she says. “No matter how nice the house is it’s a huge hurdle. If a buyer sees water or mold, it’s a hot button. Then they become more aware of other potential problems in a home.” She recommends eliminating any trace of moisture prior to putting a house on the market. “Fix the source of the problem,” she states unequivocally.

Another Island brokerage, Sandpiper Realty in Edgartown, includes a fact sheet about mold on its website. Courtney Marek, broker/co-owner, says that its inclusion was due to consumer concerns.

“People are more allergy-conscious than in the past,” she says. “Customers are looking for more knowledge.”

She encourages owners to be more proactive, to protect their investments. While she does encounter the smell of mildew in some Island homes, she says she’s never lost a deal due to a mold issue. “People will get past the smell if they think the problem can be dealt with.”

The bottom line: There’s nothing warm and fuzzy about mold. Be vigilant in keeping your surroundings dry and well maintained and mold will have to find another home.