Killing Mold - Tips for Mold Removal and Prevention

Killing Mold – Tips for Mold Removal and Prevention

My wife and I are in dire need of your advice about killing a mold problem in our home. In short, coffee-colored blotches began appearing and spreading on our four-year-old son’s bedroom ceiling approximately four months ago. Concerned that there…

My wife and I are in dire need of your advice about killing a mold problem in our home.

In short, coffee-colored blotches began appearing and spreading on our four-year-old son’s bedroom ceiling approximately four months ago. Concerned that there was moisture and possibly mold permeating from the attic above, we called in several companies that specialized in removing mold and were informed that we did indeed have mold growing on the drywall, insulation and wood above our son’s room. However, each contractor suggested a different method and product to kill the mold (ammonia versus hydrogen peroxide versus biocide). Costs also ranged from $3,000 to $7,000.

Confused by the conflicting information we received, we called in an independent “mold inspector” to assess the situation and provide expert advisement. For $900, the mold inspector visually inspected the attic and performed both swab and air-quality tests. The swab tests were sent to a laboratory, which confirmed that that there were two types of mold growing in our son’s room (green and white, also known as Cladosporium and Penicillium), and the air-quality tests done in the attic and our son’s bedroom came back extremely poor. The inspector then recommended a mold remediation contractor who again provided conflicting information on how to fix the problem.

We are very concerned about the health of our family and want to properly remediate and remove the mold situation as soon as possible.

Our Answer

The presence of mold is a potentially serious problem due to the impact it can have on your son’s health, so killing the mold and preventing it’s return is critical. For some tips on this exact situation, I turned to my trusted friend Jeff May, a certified air quality professional and author of several books on mold and mold remediation, including My House Is Killing Me.
Jeff warns that black mold removal alone will not solve this problem. You could spend thousands on remediation and unless the source of moisture is eliminated, the problem will reoccur.
So your first job is to figure out how moist air is infiltrating the attic. The most common sources of moist house air are bathrooms and dryers that are venting into the attic (or soffit), air leaks around attic hatches and pull-down stairs, and air leakage from recessed fixtures. Leaky duct work in an attic can also be a source of moisture, especially if you use a humidifier with your hot-air furnace.
Is the sheathing in your attic all black and moldy? Then you have a bigger mold cleanup job, because all of the sheathing will have to be remediated. If you have an older shingled roof, the cheapest approach is to have all of the roofing and sheathing replaced. At the same time, you can have the moldy insulation and drywall removed and replaced; this is not really a mold remediation, however.
Jeff also warns that if there is mold on the bedroom ceiling, your son should not be sleeping there. Take everything out of the room and thoroughly clean all dust from the items.
Surprisingly, Jeff and I worked on a home with a very similar situation for a television show I was involved with. It turned out that the insulation was full of Aspergillus mold and removing the mold required us to the insulation be replaced, as well as all the framing cleaned.
Another key to help preventing mold from forming in the attic space above is to make sure the attic is well ventilated. In the 20 years I spent as a professional home inspector, I rarely saw an attic that was ventilated enough to truly do a good job preventing moisture build up, and the mold that can result. Truth is that killing mold becomes a non-issue when the moisture in the wood is kept low enough. No moisture = no mold. It is as simple as that. For most homes, the best attic ventilation method is a combination of continuous ridge and soffit vents. These work together preventing and killing mold by flushing moisture out of the attic in the cooler months when mold is more likely to form, as well as flush heat out in the summer to help keep cooling bills low.