Urban Natural Homes October 24, 2013

Mold in Your Home: Is It a Cause for Concern?


The abundant moisture and humidity in the Pacific Northwest is what gives us the green, lush environment we all love. However, it also acts as a petri dish for another type of growth that might not be so admired—molds. Molds are, of course, a vital part of the natural environment. In the outdoors molds play a key part in nature by breaking down dead organic matter such as fallen leaves and dead trees. But when they are indoors they can wreak havoc by instigating allergic reactions and causing structural damage to homes. I recently spoke with James Mallory, the owner of Environix, a local mold remediation company, to learn more about mold growth in our homes. When should you check for mold? Where is it most likely to grow? How is it treated? And how big of a health concern is it?

Molds reproduce by the means of tiny spores. The spores are invisible to the naked eye, but they are literally everywhere. Floating through both indoor and outdoor air, we are constantly exposed to them. Despite many claims in the past that certain molds are toxic, Mr. Mallory is quick to point out that this has been disproved. All of the more recent studies now show that the amount of toxins released by molds is so low that it is not a health concern. That said, if you are reacting to mold it is likely because you have an allergy to molds, which is a common problem in our area. For those with mold allergies, routing out the source of the problem is, of course, an important step towards dealing with it. Even if you yourself don’t have an issue, others in the household such as family members, visitors and even pets may be reacting to elevated levels of mold spores.

Mold growth happens when mold spores land on surfaces that are damp. According to Mr. Mallory there are two ways that this can happen. The first is from a liquid source, i.e., flooding, plumbing failures, roof leaks, etc. In these situations, if the issue isn’t addressed immediately it will likely quickly lead to mold growth and eventually cause rot and structural damage. The second source is airborne, which is vapor or humidity related. This kind of damage can be more subtle and it is almost always connected to poor ventilation. To prevent this kind of mold growth you should keep the overall indoor humidity below 50%. Make sure that moisture producing appliances (dryers, stoves, dishwasher, etc.) are properly vented and run the bathroom fan while showering.  Additionally, a typical home will require additional ventilation to meet code and prevent mold growth.  Usually this is accomplished by installing constant flow bath fans or a timer switch on the existing fans. 

Two more tricky areas where mold can show up are in attics and new construction. In the case of attics, ventilation is again the culprit. When warm air rises in a home, the moisture rises with it. If there isn’t proper ventilation, this warm air will condense on the roof sheathing, providing the moisture necessary for mold growth. It doesn’t hurt to check attics once in a while to make sure things are operating as they should.

For new construction, Mr. Mallory points out that in our area the framing in a home is often saturated by rain during the build out phase.  This large addition of moisture, combined with a wet, muddy crawlspace creates an environment highly conducive to mold growth.  He says that builders can easily prevent this, but often do not take the necessary steps.  Therefore a new home should be checked out
by a professional before inhabiting.

James Mallory, Owner