During nearly every home inspection, the question comes up: "How bad is the mold?" That is because mold is everywhere; it thrives in moist environments that are present in so many of our homes and it is known to cause health issues. The good news is that not all species of mold are bad for your health and only higher concentrations of some species of mold affect most people.
Mold and mildew are often misunderstood, leaving many with the impression that the "mold terrorists" move in and force us from our homes. Mold testing and mitigation is still big business. When I hear the question "How bad is it?" I hear fear. It's easy to capitalize on things that people fear. Our tool against fear is education.
Mold and mildew require four ingredients to survive:
- Air (ubiquitous, thankfully, here on earth)
- Moderate temperatures (normal in the places in which we live)
- Food source such as wood, carpet, drywall, furniture, belongings, paper, human food, etc. (omnipresent in buildings and homes)
- Moisture (varies widely). Of the four ingredients, moisture is the only one that we can readily control.
Health Effects Vary
Health effects depend on many factors such as the sensitivity of the individual, extent and accessibility to the mold, type of mold, concentration of mold, and whether the mold is dormant.
The engineers at Criterium-Turner Engineers spend more time in nasty, moldy crawl spaces and attics each month than most people will in a lifetime, with no ill effects. Yet some individuals will experience health problems even when there are no obvious mold and mildew conditions. This extreme variation in individual susceptibility will continue to make it difficult to quantify action levels for mold and mildew.
Generally, if you see what looks like mold and/or smell something musty, then it probably is mold, which means that there is (or was) a moisture problem. Mold and mildew growth tell us that if we don't take action, fungi and more aggressive and destructive organisms will make themselves at home in our residence and cause more serious damage.
Controlling Mold & Mildew
Since moisture is the only ingredient that can be readily controlled, controlling or mitigating mold is best accomplished by 1) stopping the source(s) of condensing and/or intruding water; and 2) drying out wet building and finishing materials. Cleaning/removing the moldy materials may also be warranted, but don't use water in abundance during cleaning.
The current push for super energy efficiency will create a new round of indoor air quality problems. Active systems (such as heat recovery ventilators) will help buildings pass the "new construction" test, but proper maintenance will present challenges. More moisture problems are likely on the horizon.
When you don't feel well, you call your doctor - a licensed medical professional. When your home or building doesn't feel well (or doesn't look well), contact your licensed engineering professional and get a check-up, diagnosis and recommendation regarding proper repair.
- Nancy J. Nichols, P.E., Criterium-Turner Engineers
