The House Detective by Barry Stone, Certified Home Inspector
Dear Barry: We live in a 6-unit apartment building, and the dryer exhaust ducts for all six of the laundry rooms blow into my attic. Every few months, the landlord’s maintenance man goes into the attic to remove the lint that clogs the neighbor’s dryer vents. He insists that this is not a problem, but I’m afraid it is causing the moldy smell in our apartment. What is your opinion of this situation? Wendy
Dear Wendy: It is not legal for a clothes dryer exhaust vent to terminate within the confines of a building, either in the foundation crawlspace or the attic. Section 504.3.1 of the Uniform Mechanical Code states that: “Moisture-exhaust ducts for domestic clothes dryers shall terminate on the outside of the building…”
There are two reasons for this requirement: 1) Moisture condensation can promote the growth of fungus or mold; 2) The accumulation of lint can pose a fire hazard. Therefore, someone should extend the dryer vents in your building through the nearest exterior wall or through the roof.
The moisture from six laundries could definitely be causing mold or fungus growth in your attic. To determine possible mold infection, a professional mold consultant should conduct a thorough survey of your home to determine the types of mold that may be present and the proper means of remediation if hazardous mold is found. At the same time, a pest control operator should inspect the attic for fungus infection of wood framing and resultant dryrot.