Before we remove mold, it’s vital that you understand its cause. That way, you can make sure the mold problem doesn’t return.
In many instances, mold is caused by a prior roof problem.
Some mold problems are caused by an obvious roof issue, the causes of most attic mold problems are far more subtle and harder to identify. Remember though—all mold problems arise from a moisture problem. You cannot have a mold problem without a moisture problem.
Identifying the Source of Moisture in Your Attic
It is really important that you or a trained professional identify the source of the moisture or water problem and fix it, because if you don’t, the mold will return when the moisture returns. Even if the mold itself is removed properly.
Generally speaking attic moisture problems that lead to mold growth can be broken down into three categories:
- Roof issues/leaks
- Improper ventilation
- Improper venting from pipes and/or vents.
Let’s take a look at each one of these three causes individually so you can make sure you or a professional fix the source of the mold problem. Don’t forget these causes are also preventive measures to take (things to check in the future every now and then) to prevent mold from coming back again down the road.
Roof leaks will lead to attic mold. Below are a few ways to check for possible roof leaks:
- Check for discoloration of insulation and wood (e.g. rafters, sheathing, joists, attic side of fascia boards, etc.).
- Check roof valleys (i.e. where two roofs join at an angle), which are highly susceptible to roof leaks.
- Observe skylights, chimneys, attic windows and any portion of the attic/roof where dissimilar materials join each other (including flashings). These are common places for potential moisture intrusion.
- If you have a vapor barrier installed, check for condensation. Although this is not really a roof leak, it is nevertheless a sign of a moisture problem. And moisture problems lead to attic mold problems!
- Make sure there are no leaks coming from and around attic plumbing stacks.
Poor or improper ventilation in the attic will lead to attic mold.
- If you have a vapor barrier installed (such as polyethylene plastic) and your vents are close to the roof then you need 1 square foot of ventilation for every 300 square feet of attic floor space. Otherwise, 1 square foot per 150 feet square feet is needed.
- Air travels up to the attic. So activities such as cooking, bathing, showering, etc will produce moisture that will makes it way up to the attic. If there is poor ventilation, the moisture gets trapped in the attic and can lead to mold problems.
- Do not cover up your vents with insulation!!! We see this all the time and it is a surefire way to encourage moisture buildup and attic mold growth.
Vents and Exhaust Fans
Dryer exhaust vents, kitchen exhaust fans and bathroom exhaust fans are designed to pump moisture OUT of your home. So make absolutely sure that they terminate outside your home and NEVER in the attic. Also plumbing stacks in the attic can be a source of condensation, which can lead to attic mold growth. Plumbing stacks can also emit hazardous gases, so make sure that they too do not terminate inside the attic.
Mold doesn’t have to be a permanent problem.
We tell this to customers all the time. Don’t panic when you find mold. The health issues have been overhyped, and in most cases, a mold infestation can be remediated quickly and permanently. More importantly, don’t let mold scare you away from buying or selling real estate.