Mold in a Closet: What to Do With the Wall and the Clothes

Closets grow mold because they combine the three things mold needs: still air, a surface that stays cool, and something absorbent to eat. Take everything out, find out whether the wall itself is wet, and only then decide what to clean. Spots on a dry wall are a humidity problem you can fix; spots on a wall that reads wet are a leak, and the clothes are the least of it.

Why Closets, of All Places

A closet is the one room in the house where the door stays shut and nothing moves the air. That alone raises the humidity inside it. Add any of these and mold follows:

• An exterior wall. In winter the outside wall is the coldest surface in the room. Warm, humid air from the bedroom creeps in, meets that cold drywall and condenses, especially in a corner where insulation is thin.
• A cold corner or ceiling. Closets under an attic, against a garage or over an unheated space get the same effect on the ceiling. Mold on a closet ceiling that sits under the roof is also a common sign of a roof or attic moisture problem.
• A leak on the other side. A bathroom, laundry room or water heater closet next door can leak into the shared wall for months before anyone looks. The closet side shows it first because nobody looks at the back wall of a closet.
• Packed clothing. Clothes pressed against the wall block what little airflow there is, and cotton, wool and leather hold moisture and feed growth.

The pattern of the spots tells you which. Speckling spread across the lower part of an outside wall, worst in the corners, is condensation. A patch centered on one area, especially with a tide-line stain or bubbling paint, is water arriving from somewhere. Growth that starts at the floor and climbs points to water in the bottom of the wall, which is covered in the baseboard mold guide.

What to Do, Step by Step

1. 1Empty the closet and bag the moldy items. Wear an N95 mask and gloves. Put anything with visible growth or a musty smell into plastic bags before carrying it through the house, so spores do not scatter on the way. Leave the closet door open and point a fan out of the room, not into it.
2. 2Check the wall with a moisture meter. Press a pinless meter against the moldy area and compare it with a wall in the same room that looks clean. If the moldy wall reads close to the clean one, the growth is from humidity and condensation. If it reads much higher, water is in the wall, and cleaning the surface will not end it.
3. 3Clean surface mold on hard surfaces. On painted drywall, shelves and closet rods, scrub with a detergent solution, wipe with a damp cloth and let it dry completely. The EPA's guidance is that detergent and water is enough for hard surfaces; bleach is not required and does not reach into drywall paper. If the drywall is soft, crumbles, or the mold keeps coming through after cleaning, it needs to be cut out, which the drywall mold guide explains.
4. 4Launder, clean or discard the clothes. Sort everything into three piles, as below.

The EPA's line for doing it yourself is about 10 square feet of growth, roughly a three-by-three-foot patch. Beyond that, or anywhere the wall reads wet, it is a job for a professional.

What to Do With the Clothes

Most clothing survives closet mold if it is dealt with quickly.

Do not put moldy clothes back until the closet is dry. They will pick the smell right back up. The clothes guide covers washing methods and stains in detail, and the leather guide covers shoes and jackets.

Is Mold on Clothes in a Closet Dangerous?

For most healthy adults, a few spotted garments in a closet are an irritant, not an emergency. The EPA and CDC describe mold's effects as allergic reactions, stuffy nose, itchy eyes, coughing and worsened asthma, and they name people with asthma, allergies or weakened immune systems as the ones most at risk. Black spots on a jacket are not a sign of "toxic black mold"; color does not tell you how harmful a mold is. If you sleep next to that closet and wake up congested, clean it and keep it dry, and talk to a doctor if symptoms continue.

When It Is a Wall Problem

If step 2 showed a wet wall, or the mold returns within a few weeks of a thorough clean, the source is inside the wall. That means a plumbing leak, a window or siding leak on the exterior side, or a condensation problem bad enough to soak the drywall. Cleaning the paint will not reach it. The drywall usually has to come off far enough to see the back side and the framing, the leak has to be found and fixed, and the cavity has to be dried and treated before it is closed up. Wet drywall begins growing mold within 24–48 hours, so a leak that has been feeding a closet wall has almost always grown more on the back than on the front.

That job, removing a section of wall under containment, drying it and rebuilding, runs about $1,500–$3,500 when it is one closet wall. If you want it assessed, (888) 840-6512 is answered 24/7 and connects you with an IICRC-certified restoration company that serves your area; the company gives you an arrival window for your address on the call.

Keeping It From Coming Back

• Leave a few inches between clothes and the outside wall, and do not store boxes flat against it.
• Keep the bedroom under 50 percent humidity. A small dehumidifier in the room does more than one in the closet.
• Swap a solid door for a louvered one, or leave it open a crack at night.
• Never put away damp clothes, gym gear or dry cleaning still in its plastic.
• Check the closet after heavy rain and after any leak in the room next door.