What Does Mold Smell Like?

The EPA says some compounds produced by molds have strong smells and are quickly released into the air, and that these microbial volatile organic compounds, or mVOCs, can be the source of the moldy odor or musty smell frequently associated with mold growth. It says a moldy odor suggests that mold is growing in the building and should be investigated, and that you may suspect hidden mold if a building smells moldy but you cannot see the source, or if there has been water damage and residents are reporting health problems.

The EPA says the health effects of breathing mVOCs are largely unknown, although exposure has been linked to symptoms such as headaches, nasal irritation, dizziness, fatigue and nausea, and more research is needed on everyday indoor exposures. The CDC says damp and moldy environments may cause a variety of health effects or none at all, that for some people mold can cause a stuffy nose, sore throat, coughing or wheezing, burning eyes or skin rash, that people with asthma or mold allergies may have severe reactions, and that people with weakened immune systems or chronic lung disease may get lung infections from mold.

Controlling moisture is the fix. The EPA says there is no practical way to eliminate all mold and mold spores indoors, so the way to control indoor mold growth is to control moisture, by fixing leaks, keeping indoor humidity between 30% and 60%, and cleaning and drying damp or wet building materials and furnishings within 24 to 48 hours. It says that if the moldy area is less than about 10 square feet, roughly a 3 foot by 3 foot patch, in most cases you can handle the job yourself, but if there has been a lot of water damage or mold covers more than 10 square feet, it points to its guide on mold remediation in schools and commercial buildings, which also applies to other building types.