Mold Questions from Ann Arbor Homeowners, Landlords and Renters

Usually not in the 911 sense, but act within days. The urgent part is stopping the water and drying out, because the EPA says to dry water-damaged areas and items within 24 to 48 hours to prevent mold growth. Move sooner for large areas, mold after a sewer backup, mold in the ductwork, or anyone in the home with breathing problems.

The EPA and CDC say mold can cause allergic and irritant reactions, such as a stuffy nose, coughing, wheezing or itchy eyes, and people with asthma, allergies or weakened immune systems may be more sensitive. If anyone in the home has symptoms, see a doctor. This site does not give medical advice.

Color doesn't tell you how risky a mold is, and the cleanup is the same either way: fix the water and remove the growth carefully. Any mold can bother people who are sensitive to it. Treat a large dark patch like any other large mold problem. See black mold removal.

Often, if it is small. For areas under about 10 square feet, EPA says homeowners can often clean it themselves. Scrub hard surfaces with detergent and water, wear gloves and eye protection, and dry the area fully. Moldy drywall, carpet and insulation usually have to be cut out. Fix the water first, or the mold tends to come back.

Usually not. EPA says testing usually isn't needed when you can see mold, and Michigan's health department doesn't recommend routine testing. The plan is the same either way: fix the water and remove the mold. Testing helps when you smell mold but can't find it, during a home sale, in a dispute, or as a clearance check after the work. See mold inspection and testing.

An air test pulls a measured amount of indoor air through a collector, usually compared with an outdoor sample, to show which spores are in the air. A surface test uses tape or a swab on a stain to identify what is growing there. Fixr puts air tests at about $500 to $700 and surface tests at about $150 to $200.

Michigan has no rule against it. Still, if you pay for testing before or after the work, it is sensible to use a tester who is independent of the remediator, so the person checking the result isn't the one who quoted or did the job. A clearance test is a check, before walls are closed, that the area is clean and dry.

Michigan law (MCL 554.139) requires landlords to keep rentals fit for the use intended and in reasonable repair, and to follow state and local health and safety laws. Mold isn't named in it, but the leaks behind mold usually fall under repair. Tell your landlord in writing, with photos and dates. This is not legal advice, and don't withhold rent without legal advice.

Ann Arbor's Rental Housing Services inspects rental units about every 30 months, but the city says it cannot test for mold or recommend anyone to test. If inspectors can see mold, the owner must treat the visible surfaces. Tenants must contact the landlord first, then can call Rental Housing Services at 734-794-6264 to request a complaint form.

U-M students can contact Student Legal Services, which helps students with housing matters, and Beyond the Diag, U-M's off-campus housing program. In the City of Ypsilanti, rentals need a certificate of compliance and the city takes property maintenance complaints. Legal Services of South Central Michigan offers free legal advice to low-income residents. See mold in rentals.

Summer dew points average about 61°F in July and August at Detroit Metro airport, and basement walls and floors are often cooler than that, so moisture can condense on them. Add soil moisture and a little seepage, and mold can grow on drywall, carpet or stored boxes. The EPA suggests keeping indoor humidity below 60 percent, ideally 30 to 50 percent. See basement mold.

After the June 25 to 26, 2021 storm, which brought about 4.8 inches of rain to parts of Ann Arbor, the city recommended footing drain disconnection, a check valve on the sanitary sewer lead, extended downspouts and soil graded away from the house. A working sump pump and a dehumidifier help too. See mold after basement flooding.

In a long Michigan heating season, warm, moist air leaking up from the house can condense on cold roof sheathing. Bath fans that vent into the attic instead of outside make it worse, and ice dams can add roof leaks. Better air sealing, ventilation and outside-vented fans are the usual fixes. See attic mold.