As our homes become increasingly airtight, black mold is more likely to grow, and its presence can cause serious health problems and structural issues as well. Surprisingly, dangerous black mold can also be gray, brown, purple, pink, or fluffy-looking in appearance, and all forms affect infants, little children, those with lung-related diseases, immune suppression, or allergies, and the elderly. In order for it to grow, this toxic element needs both a moisture source and a food source. Because our homes are a major food source (wood, carpeting, drywall, wall paper and other sources) for black mold, the key is to remove the moisture that exists there.
Black Mold and Your House’s Indoor Air
The relative humidity in your house should never exceed 55%, and ideally, it will be lower than that. If you live in an environment where the outdoor humidity is usually above 55%, the same is probably true indoors., and you will want to invest in a reliable (hygrometer moisture meter) that will give you an accurate reading.
If you determine that the amount of moisture in your house is excessive, these are some precautions you can take:
- Purchase a reliable dehumidifier. The source of your problem may be an unused space in your home or your basement, and it will be much less expensive to operate a dehumidifier in those spaces than it would be to run air conditioning there.
- Make sure that there is no water around your home’s foundation walls. This may happen because your yard was not graded properly and the water flows in the wrong direction, and the only solution will be to re-grade the yard. Otherwise, water will seep into the foundation through condensation and cracks, the humidity level will rise, and black mold will have a source for moisture. In addition, be sure that the water from the gutters and downspouts flows away from the house as well.
- Repair any water pipes that are leaking to avoid generating moisture for black mold. To find leaks where the pipes are concealed, look for indications of discoloration, loose drywall tape, and drywall warping. See if you can hear dripping, and find out if your water meter registers water usage even when everything has been turned off. To reduce condensation further, you might also want to consider insulating the waterworks in your home.
- Get rid of any ice dams that form on your roof in the winter. If you notice icicles on the eaves, this may be a sign that you have this problem, and rainwater may be backing up under the roof,—saturating the structure, insulation, and sheathing. If it runs down inside the exterior wall, rainwater will provide a great deal of moisture for the formation of black mold. In this case, you may not hear it dripping, but the damage will be done.
Taking Care of Crawl Spaces
If this is a concern, you can install a barrier of 4-6 millimeter polyethylene plastic above the ground and prevent moisture from the soil from seeping into your house. Having a damp crawl space can result in wood rot on the beams, sills, and joists located above it, because these mold spores enter the house through small crevices and cracks. In addition, providing proper ventilation of a craw space by placing vents on opposite sides is another way of minimizing humidity and prevent black mold.
When you Build a new Home
In this case, use sheet-membrane waterproofing around every door and window opening, and make sure that all the valleys and eaves have water- and ice-dam protection. Make certain that the ventilation for the attic is sufficient, and provide rigid insulation for every foundation wall. In addition, all combustion appliances should be ventilated to the exterior of the structure—including fireplaces, water heaters, space heaters, and clothes dryers. All high-humidity areas—such as bathrooms, showers, and laundry rooms—should be well ventilated with a high-quality exhaust fan.
Along with that, the air intake of your house’s interior should be slightly more than the air that is released to the outside. If you fail to provide for this, pollutants and moisture will be drawn inside, creating an environment that will become a breeding ground for black mold.