Our Guide to Mitigating Household Mold Growth
Many homeowners -- particularly those living in environments with high-humidity climates and/or seasonal weather -- harbor concerns about mold growth. Seeing spots form and spores disperse throughout the home can be horrifying. One might expect areas of mold around sinks and bathtubs or in dishwashers and grout lines. However, mold that forms due to unseen leaks and in dark, damp spaces between walls might go unnoticed until the issue has ballooned. Thankfully, the majority of household molds are non-toxic -- simply allergenic -- and do not cause major health issues in most people. Additionally, mold growth can often be limited -- if not completely eradicated -- by taking a few simple and inexpensive maintenance steps around the home. Follow below for more information about mold and how to mitigate household mold growth alone and with professional help.
All About Household Mold Growth
Which Kinds You Might Find
According to Courtney Campbell in a July 2020 article for Wide Open Country, there are twelve types of mold commonly found in residences -- be they apartments, condos or single-family homes. The Center for Disease Control outlines three -- “Cladosporium, Penicillium, and Aspergillus” -- as occurring most frequently, but nine other types may also inhabit dwellings. These include Acremonium, Alternaria, Aureobasidium, Chaetomium, Fusarium, Mucor, Stachybotrys -- also called “black mold” -- Trichoderma and Ulocladium. There are two categories of mold: toxic and allergenic.
Campbell writes in her article for Wide Open Country that acremonium is a toxic mold that “turns into a powdery substance that could be pink, grey, orange or white.” Acremonium is commonly found in “small moist areas,” including “humidifiers, cooling coils, drain pans and window sealants.” Acremonium is an especially concerning strain because exposure can “lead to various health problems, including bone marrow and immune system diseases.” Other toxic molds include aspergillus, stachybotrys -- black mold -- and ulocladium. Allergenic molds -- the second category -- often cause respiratory infections, hay fever and other allergic reactions as well as contact skin infections.
Types of allergenic molds include alternaria, aspergillus, aureobasidium, chaetomium, cladosporium, fusarium, mucor, penicillium, trichoderma and ulocladium. Aureobasidium and chaetomium are most likely to cause skin and nail infections and thus should never be touched. Unlike garden-variety allergenic molds, toxic molds are uncommon and rarely horrifically dangerous. Some residents might not notice any ill effects from exposure to allergenic mold, while others might be more sensitive.
Where You Might Find Household Mold
Homeowners often find mold in the grooves and interstitial areas of home appliances -- from dishwashers and refrigerators to electric toothbrushes and washing machines. However, mold spores might find their way into more insidious and difficult to address areas of the home. As Lauren Smith McDonough writes in her article “10 Sneaky Places Mold Might Be Hiding in Your Home” for Good Housekeeping, “there are places you expect mold growth, like on your shower liner or in the forgotten corner of your basement...but there are other spots prone to growth that many people overlook until it's a major problem.” When mold is not readily visible, it is rarely checked for by homeowners. Thus, hidden and/or trapped mold is often left unmitigated, permitting it to spread and cause or contribute to a number of health issues.
Dark and damp areas are popular breeding grounds for household mold. As one might expect, according to the CDC, mold will often grow “around leaks in roofs, windows, or pipes, or where there has been flooding.” However, what one might not expect is that “mold grows well on paper products, cardboard, ceiling tiles, and wood products” and -- like a pest infestation -- can be difficult to thoroughly get rid of. The CDC notes that “many building materials provide suitable nutrients that encourage mold to grow,” making homes particularly at risk. Julie Sheer writes in an article for Houzz that “crawl spaces with drains, walls plumbed from bathroom to bathroom and between floors” are especially susceptible. “Incorrectly sealed tubs and faulty construction” can also cause major issues, as such mistakes can “cause water to seep in crevices and cause big problems over time,” writes Sheer.
Common Causes of Mold Growth
According to the Clean First blog post “10 Common Causes of Mold in Homes,” both small, everyday occurrences that might seem inconsequential and major disaster events can cause mold growth. Homeowners should always be on the look-out for mold in moist spaces with poorly circulated air. The post notes that “mold behind drywall may be one of the most common household problem areas as drywall, wood, and cotton are ideal food sources.”
Ceiling mold -- particularly in bathrooms and kitchens -- is often common when spaces lack appropriate ventilation. As one might have guessed, “persistent humidity,” a leaking roof and leaky pipes are all common causes of mold growth. Other common causes of mold outlined by the Clean First post include an accumulation of “wet and damp clothing,” “flooding,” “a damp basement,” “foundation dampness” and/or “a leaking air conditioning system.” Homeowners should keep in mind that significant events like a burst pipe or flood across the foundation are not necessary to encourage mold growth. Kathy Orton explains this in a 2013 article for The Washington Post, quoting Washington-based mold remediation specialist Nelson Barnes Jr. Barnes notes that while “‘most people think you have to have a water intrusion or pipe burst in order to grow mold...if you have relative humidity above 60 percent and you have organic debris, which we all have, which is dust, you can grow mold.’”
Health Issues with Mold Exposure
Human health consequences of exposure to mold within the home vary from mild to extreme. Exposure to allergenic mold can cause mild disturbances like skin irritation and infection and respiratory irritation and infection. However, toxic mold exposure can also cause neurological issues and severe acute and long-term health issues. In a recent article for Healthline, Marc Meth, MD, FACAAI, FAAAI and Ann Pietrangelo outline the range of risks.
Meth and Pietrangelo note that most homes have at least some nontoxic mold spores floating about and that “having mold in your home won’t necessarily make you sick.” However, “it does have the potential to cause certain health issues,” particularly if the spores are touched or inhaled. These health issues include “allergy-type symptoms” like “runny nose and congestion...eye irritation...sneezing...coughing...sore throat...skin rash...headache...lung irritation [and] wheezing.” Those at a higher risk for “complications like infection” are those suffering from allergies, COPD, a compromised immune system and/or asthma. Meth and Pietrangelo note that “exposure to a large amount of mold can cause a more serious reaction.” If this is ever the case, those exposed and experiencing severe reactions should seek medical intervention.
How to Address Household Mold Growth
Quoting Nelson Barnes Jr., Orton writes in her article for The Washington Post that mold is just a plant. According to Barnes, “‘if you didn’t touch it or eat it, it wouldn’t bother you.” Health issues arise from exposure to mold when “the reproductive facet of that plant shotguns spores into the air.” Barnes explains that “it’s those microbials that we breathe in’” that can cause discomfort and major health issues. As such, “the absolute biggest thing in mold remediation is the evacuation of spores.” While surfaces can be rid of mold simply by wiping down with alcohol and other chemicals, the spores can travel and transplant themselves around the home.
Some types of mold -- particularly those which are toxic or are suspected in unreachable portions of the home -- should only be addressed by trained experts. Others, however, can be addressed by the homeowner with household cleaners found in nearly every drug store. However, should homeowners try these methods and still be plagued by a musty smell, chest, throat or skin irritation or the reappearance of mold, a specialist should be contacted. Whenever one comes into contact or proximity with mold, appropriate protective measures must be in place. One should wear gloves, cover the eyes and consider covering the mouth and nose as well.
In her article for The Spruce, Mary Marlowe Leverette explains “how to get rid of mold from every home surface.” Leverette writes that products that kill mold include “chlorine bleach…[which] should be diluted before using,” “hydrogen peroxide” and “distilled white vinegar,” all used separately from each other. Borax and baking soda can also keep mold away as both “have a high pH that inhibits the growth and survival of mold.” Leverette warns that mold cannot always be easily removed from clothing, carpeting and other textiles, but if it “is caught early,” it typically can.
Cost to Have Mold Addressed Professionally
According to the Home Guide cost analysis brief “How Much Does Mold Removal & Remediation Cost?,” professional mold remediation typically costs “$15 – $30 per square foot.” The cost of remediation varies based on ease of access to the source of the mold, extensiveness of the mold and toxicity of the type of mold. The Home Guide brief notes that “the average cost of mold remediation is $2,325, with most homeowners spending between $1,500–$3,150.” Small-scale jobs cost around “$500 - $1,500...while a larger job costs around $3,000–$6,000.”
However, in rare cases, “mold remediation costs can escalate to tens of thousands of dollars if the mold has spread and the problem is severe.” Homeowners should seek help immediately if they suspect severe mold development and/or if a flood or substantial leak has occurred. This is because “if untreated for too long, additional costs mount.” In addition to causing increased exposure and health problems, leaving mold addressed can cause it to spread to “drywall, lumber, subflooring, siding, and other potential areas.”
Preventing Mold Growth
Homeowners can limit mold growth by cleaning out gutters and drains around the home frequently, removing debris and moisture. They can also open bathroom windows and doors to increase ventilation after taking a shower. Household appliances should be cleaned and towel-dried often after use, particularly dishwashers, coffee makers and clothes washing machines. Quoted once more by Kathy Orton, mold remediation specialist Nelson Barnes Jr. recommends ensuring the home is properly ventilated and both proper temperature and relative humidity are maintained. Barnes suggests simple maintenance like “replacing air filters regularly,” “checking that the grading near the foundation causes water to run away from the home” and “running a fan to promote air circulation,” particularly in moist environments.
Here at Living Deep, we are deeply concerned about and very much aware of the links between home health and human health. We hope this information -- and our tips -- on household mold growth will help you keep your family -- and the spaces you share -- healthy and comfortable.