Mold on Furniture: Sofas, Upholstery and Wood Pieces

Mold needs moisture. The EPA says moisture is the most important factor influencing mold growth indoors, and that mold can feed on organic materials such as cloth and wood, both common in furniture.

Common causes:

• Furniture against outside walls. NDSU Extension warns that there is a chance mold might be growing behind furniture, particularly against an outside wall. When you look for mold, TDLR says to pay special attention to hidden areas including behind mirrors and furniture.
• High humidity. NDSU says mold growth is likely with humidity levels above about 70%.
• Spills and food stains. UF/IFAS Extension lists remove food stains from furniture as quickly as possible among its mildew-prevention steps.
• Leaks and floods. The EPA's flood guide says you may see or smell mold on clothing, drywall, furniture, cardboard boxes, or books after a flood, and that it can hide under cushions.

If mold is growing on the back of furniture, look at the wall behind it too. A moldy wall is a building problem, not a furniture problem. See mold on walls.

Mold on furniture by material

The hard line for upholstery comes from how mold behaves in porous materials. The EPA explains that molds will infiltrate porous substances and grow on or fill in empty spaces or crevices, so the mold can be difficult or impossible to remove completely. TDLR says mold is difficult to clean from absorbent (porous) surfaces such as drywall, carpet, fleecy furnishings and insulation, and that these should be removed and discarded.

These steps for upholstered furniture mold come from University of Georgia Extension and Texas A&M AgriLife Extension. They're for surface mildew, not mold that's grown into the cushions.

Protect yourself. Wear gloves, goggles and an N95. The CDC recommends at least a NIOSH Approved N95 respirator and says not to touch mold with bare hands.

1. Brush it off outdoors

UGA says to remove loose spores from upholstery by brushing with a soft-bristled broom, outdoors if possible, to avoid scattering spores in the house. Texas A&M agrees: clean mildewed items outdoors. Wash the broom afterward.

2. Vacuum

Texas A&M recommends a HEPA vacuum, if available, to remove visible mold growth, then discarding the bag. With a regular vacuum, empty the bag outdoors right away.

3. Dry it, in the sun if you can

If the piece is damp, UGA suggests drying it with a fan and heater and, if possible, placing it in direct sunlight and air to stop mold growth. (Wood frames are an exception; see below.)

4. Treat the remaining spots

Texas A&M suggests sponging remaining mildew with thick suds or a commercial cleaner designed for the type of material, wiping with a barely damp cloth, then wiping stains with a cloth dampened in diluted alcohol (1 cup rubbing or denatured alcohol to 1 cup water). Dry thoroughly.

UGA lists a commercial dry-cleaning solvent as another option for upholstery.

5. Watch the cautions

UGA's cautions for upholstery are worth reading before you start:

• Overwetting with water may cause the finish on the upholstery fabric to migrate and leave a ring.
• Solvents can destroy the foam padding used in upholstery, so don't soak the fabric.
• Alcohol will damage acetate, triacetate, modacrylics and acrylic fibers.
• Always pretest each cleaning agent on an inconspicuous area first.

Bleach is a last resort, not a first step. An older Texas Cooperative Extension sheet suggests that after brushing, vacuuming and detergent suds, one-quarter teaspoon chlorine bleach to one cup of water can be used on remaining mildew. Only use it on fabric you've tested for color loss, and never mix it with other cleaners. The EPA says bleach is not recommended as a routine practice during mold cleanup.

A sofa can look clean outside while the cushion foam is moldy inside. Signs: a musty smell when you sit down, spots on the inner side of the cover, or a cushion that never quite dries after a spill.

What to do:

1. Unzip and look. Check the foam and the batting, not just the cover.
2. Covers. If the label allows washing, the cover can go through the laundry. Our mold on clothes guide covers washing fabric with mold.
3. Foam inserts. If the foam is stained or smells musty, replacing the insert is usually easier and more reliable than trying to clean it, for the porous-material reasons above.
4. The frame and deck. Check the platform under the cushions and the frame for spots.

If the whole sofa got wet, Texas Cooperative Extension says furniture that has been heavily soaked with flood waters might not be salvageable. For a special piece, it suggests removing the upholstery and stuffing, throwing away cotton stuffing, and drying the frame slowly. NC State recommends stripping it to the frame and getting a reupholsterer's estimate to decide whether to reupholster or buy new.

Solid wood is the most salvageable furniture material. The EPA says treated or finished wood can be cleaned with mild detergent and clean water and allowed to dry. Our mold on wood guide covers sanding, mold under finishes and when wood is too far gone.

Drying is where people go wrong:

• Dry it slowly, out of the sun. Texas A&M says to dry furniture slowly out of direct sunlight because sun will warp furniture, and that it may take several weeks to several months.
• Wait for low moisture. Kentucky Extension says wood furniture should dry out to a moisture content of 20% or less before making any necessary repairs. NC State notes mildew may keep growing on a frame until the wood drops below 20 percent.
• Don't refinish early. Texas A&M says do not refinish or wax until thoroughly dry.
• Open it up. Remove drawers and doors so air can reach every surface.

After a flood, Texas A&M AgriLife Extension says to remove all furniture, bedding, and carpeting to outdoors to be cleaned and dried (or discarded). For furniture it adds: brush off mud, remove all drawers and doors, discard flooded padding, and use cleaners designed for the material.

The EPA's rule for the rest: throw away anything that was wet with flood water and can't be cleaned and dried completely within 24 to 48 hours. Kentucky Extension agrees that porous items such as couches should be discarded, but suggests weighing each item's condition and sentimental or monetary value.

Photograph everything first. Texas A&M advises taking photos for use as an inventory for your insurance claim. See mold after flood Texas for the rest of the house.

• Pull furniture off outside walls. Leave a few inches for air. Museum conservators avoid storing collections directly against outside walls where they are more susceptible to high RH, condensation, and leaks.
• Control humidity. The EPA recommends indoor humidity below 60 percent (ideally between 30 and 50 percent), and TDLR suggests no higher than 50%. A dehumidifier for mold helps in damp rooms.
• Use fans. UF/IFAS suggests ventilation fans to draw moist air out of the home and ceiling fans to circulate the air.
• Clean up spills fast and dry cushions completely after any upholstery cleaning. The EPA lists drying carpets, drapes, furniture, and other furnishings promptly after cleaning as a moisture-control step.

If mold keeps returning on furniture in the same room, or you find it on the wall behind a piece, look for the moisture source. A licensed mold testing company in San Antonio, Houston or another city on our Texas page can inspect. A separate mold removal company handles cleanup, because Texas law says a license holder may not perform both mold assessment and mold remediation on the same project. Verify licenses with our license check tool and read how we verify companies.

If someone in the home has symptoms, see a doctor. A mold test doesn't diagnose illness, and the CDC says individuals with persistent symptoms should see their physician.