GET THE FACTS ~ Healing Homes Guru

Mold exists naturally in the world and can be found almost everywhere, including our indoor environments. Molds live in our air, our soils, and even our foods. If you are a fan of bleu cheese or tempeh, for example, you can be thankful for the molds that produce it.

Mold is a group of fungi that thrive best in humid/ damp spaces. Many molds inside our homes lurk behind our walls and in our ducts hidden from view. It has been estimated that anywhere from 50% to 70% of American homes have mold issues. Experts from the David Asprey produced documentary Moldy (2015), claim “environmental mold is far more dangerous than lead paint or asbestos.” In order to grow, mold requires both an organic food source—the paper facings of conventional drywall being the largest food source inside a home—and moisture, which my homes guard against by weather protecting materials upon delivery to the job site and further mitigate by using interior finishes that absorb and retain excess moisture. Mold in buildings is a concern because it can lead to a host of acute or chronic health problems: stuffy nose, wheezing, asthmatic reactions, immune deficiency, even cancer. That “musty” or “moldy” odor inside a home is a sure sign that “mycotoxins”—that is, the toxic gas byproducts of microbial metabolism—are present. Bottom line? Preventing the growth of mold in buildings is critical to occupant health and building integrity, and some would argue the single most important factor in a healthy home design. One more thing, and this can’t be said enough: The key to mold growth and therefore healthy indoor air quality begins and ends with moisture control.

The best place to learn about mold is the U.S. Environmental Protection Agency (EPA). Here’s the best overview I know of. And actually, Wikipedia has a nice summary as well.

MY APPROACH

Most builders’ efforts to control moisture is to make a home as tight as possible to seal out moisture. Passive House builders are notorious for reducing air exchanges to an absolute minimum. They do so by typically super insulating, sealing every nook and cranny with synthetic tapes and compounds that fill air gaps, then reintroducing a very strict and controlled amount of treated air.