Homeowners don't usually notice attic mold until it's pointed out by a building inspector. And unfortunately, they don't call an inspector until they're getting ready to sell or buy a home.

In the majority of moldy attics, the sheathing (boards or plywood covering the roof framing) will be black and discolored. If you can see discoloration, then the mold problem needs to be addressed.

Where Does Attic Mold Come From?

The major source of mold in attics is improper ventilation. This can be caused by:

• Soffits that aren't ventilated or blocked by insulation.
• A lack of roof vents or vents properly placed on the roof.
• The use of different type of roof vents used to vent the same attic space.
• No ridge vents across the length of the roof.
• Bathroom's exhaust venting into the attic. Moisture and cold air outside creates condensation, creating conditions for mold growth.
• High humidity levels inside the home during the cool dry season passing through openings that lead into the attic.

The other major cause of attic mold is water from leaks in the roof and chimneys with improper flashing. These issues, coupled with other mold-friendly conditions, create mold problems and must be corrected. Find out how here.