Who’s Afraid of the Big Bad Mold Spot?

In this case, the mold is growing on the exterior siding. Time for a chemical treatment and power wash!

Managing Mold: Blue Door Painters Discusses the Household Nuisance and What to Do About It

You open the door to your laundry room, and are greeted by a dark, irregular stain with a fuzzy texture on the wall above your washing machine.  As you walk closer to it, you notice a dank, musty smell.  You don’t have any personal experience with household mold – other than periodically bleaching off the black stuff growing between your shower tiles – but you have a vague memory of hearing about Black Mold on the news a couple years ago, and learning that it was Really, Really Bad.  Screaming, you drop your laundry and run upstairs to book a hotel room.

But before you short sale your home, take a few minutes to learn the basics about mold, mildew, and all the other microscopic fungal visitors that plague households.  While it’s true that some forms of mold, in some locations, can be a big problem, in most cases mold issues can be remediated with straightforward moisture control, substrate replacement, and coating solutions.

Mold and mildew are both microscopic members of the Fungal Kingdom.  While in the scientific world ‘mildew’ is a type of fungus that grows on plants, in the common parlance ‘mildew’ has come to mean a relatively specific subset of mold species that grow in bathrooms.  Without being particularly precise about the actual genus of the organisms involved, ‘mildew’ tends to refer to the relatively harmless growths that are found (and removed regularly) from bathrooms, while ‘mold’, or ‘black mold’ is the home-destroying menace that inhabits a house’s HVAC system.

In actuality, there are over 100,000 species of mold, and the spores (microscopic ‘seeds’) of many varieties are in the air all the time.  It is not possible to rid your home of mold spores altogether, nor are mold spores in small amounts particularly dangerous.  It is only when the conditions are right for those spores to bloom, populating your home in high concentrations, and when you are dealing with a particularly virulent genus of mold, that you have the severe ‘black mold’ problem that caused such a scare in the past twenty years.

Mold spores in the air need two things in order to grow: a source of organic material, and a source of moisture.  Unless your home is entirely built of plastic, it is full of organic material: wood, drywall, masonry, carpet, linens, furniture: all of these can provide ideal food for a mold bloom.  Moisture is the element that is ideally under your control; mold needs its environment to be constantly moist in order to bloom.  For that kind of moisture to be found in the home, either something is leaking, there’s a temperature differential that causes condensation to collect constantly in the same spot, or the area lacks adequate ventilation.

You will usually notice mold because you can see it when it blooms.  Some types of mold will appear regularly in your bathtub or shower (the most moist area of your home), and can be eliminated with a bleach-based cleaner.  Other molds will bloom on walls or ceilings.  These molds can be tested for their particular strain; the molds of the stachybotrys genus are more virulent, and need to be carefully contained during renovation so that they do not release toxic spores into the air in high quantities.  Other forms of mold, though they are not as vicious to the respiratory system, should also be removed.  Seeking a professional mold diagnosis is a good precaution before proceeding with mold removal; an expert has methods of determining the difference between a nuisance and a major problem.  The expert will also help you determine if your mold bloom is localized, or if it is actually blooming in the HVAC system.  In the HVAC system, mold is a much greater risk because the spores and toxins are circulated throughout the household air. A localized bloom, however, is a relatively mundane and straightforward problem.

Once the mold variety and the degree of risk have been established, you need to figure out the mold’s source of moisture, and take steps to eliminate it.  Find and fix any leaks, and adjust the ventilation in the moldy area to ensure that the area stays dry.  If you skip this critical step, you may find yourself staring at a moldy patch in the exact same spot three months after fixing it.

Finally, the moldy area of substrate (drywall, wood, masonry, etc), needs to be carefully removed, taking care not to disturb the spores, and replaced with a fresh patch of substrate.  Then the entire region should be primed and recoated, preferably with moisture-resistant and mold-resistant coating products.  Intelligent use of coatings can go a long way toward stopping the growth of mold, as a good coating can provide both a moisture barrier and a chemical layer that is toxic to the mold and makes it unable to safely access the vulnerable substrate.  Moisture-resistant chemicals and mildewcide additives have been mixed into many top paint brands for exactly that reason; Blue Door Painters estimators are happy to discuss product options with you and provide you with a full-service mold remediation treatment.