What Causes Mold on Furniture?
Mold growth on furniture is caused by excess humidity or saturation due to wet carpeting.
Is the mold growing on the backside of furniture near an exterior wall?
This is caused by a combination of poorly insulated exterior walls and elevated indoor humidity. If a house is very well insulated (i.e. a modern 2×6 wall) this kind of mold growth will only occur in homes with extremely high humidity. In older homes with poor or no insulation, this can happen in fairly dry houses.
My exterior walls are not insulated
No surprise here, the best solution is to insulate the walls via blown in insulation. Check your local utility company for rebates and discounts. If insulating the walls isn’t feasible, you can still address the mold issue by pulling the furniture away from the walls and increasing the ventilation and temperature.
My exterior walls are well insulated
Focus on lowering the indoor humidity (<50% in the winter). You can achieve this by a combination of increasing the ventilation. The least expensive way to pull this off is typically by running your bathroom exhaust fan continuously.
Is the mold growing on furniture in the middle of the room?
This is caused by extreme humidity (70%+). If you live in a hot/humid climate, you’ll need to utilize your air conditioner to drop the humidity. If you live in a cool climate (and the problem occurs in the winter), you can lower the humidity by improving your ventilation and raising the heat.
You’ll need to purchase a relative humidity gauge to monitor the RH. Your goal is to keep the winter RH below 50%.
Example of Interior mold growth due to furniture placed too close to a poorly insulated exterior wall
Mold growth on painted table legs due to elevated humidity.
In this case, the mold growth is likely feeding off the settled dust that has accumulated on the painted surface. Mold growth like this only occurs in rooms with very high humidity levels.
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What would cause mold on my dresser in a carpeted room?
The first goal is determining whether the mold is due to excess humidity or a liquid water leak/intrusion. In most cases, mold on the furniture is due to a combination of excess humidity and poorly insulated exterior walls. When a dresser is right against an exterior wall, the airflow is restricted and condensation can form. In time, this condensation creates an environment conducive to mold growth.
Try to keep your humidity beneath 55% during the winter months. Often this can be achieved by simply running your bathroom exhaust fan 8-12 hours per day. Also, if your home has poorly insulated walls, keep furniture and bedding 3-4″ away from all exterior walls. Lastly, be careful with humidifiers, which can greatly exacerbate the issue.
How can I clean the mold off the back of the dresser ? The back of my dresser looks like the one in your picture.
Typically a Borax / water solution works well. You’re not relying on the killing power of solution, but rather the detergent/cleaning action. You’ll need to lightly scrub the surface to dislodge the mold growth. In many instances, some staining will remain in the wood. This is simply residual pigment and is not a health issues. As always, wear a tight fitting respirator/mask to prevent inhalation of the spores you’ll dislodge when cleaning. All cleaning should be performed outside of the home. Immediately launder all clothing worn during the cleaning process.
My daughter has a skin condition that reacts to warmth and light. Living in a Florida home, we have central air at 68F, but also a window ac unit running at all times in her bedroom as she needs it at around 65F. She also has fans running on either side of her bed and blackout curtains. Two days ago, I wiped down her furniture and changed all her bedding so I know everything was ok. 2 days later, I have discovered the top front of all her wooden dresser drawers, fabric Shadowbox, linoleum floor, dust ruffle on the opposite side of her bed from window ac unit. There is also a ceiling ac duct in the ceiling about6 feet in front of the dresser. What do you think? Is there mold in the ceiling ducts? Is it the window ac? Both? Please give any advice as soon as you can. Do we call in a service? Who is reliable? Stanley Steamer had an ad for ductwork. Thanks so much. I don’t know if I can figure out how to download photos. Sincerely, John
The amount of mold growth in the photo is quite severe. This type of mold is typically only found in rooms with highly elevated humidity. I recommend installing a relative humidity gauge. Your goal is to keep the RH below 55%. The lower the temperature, the higher the RH. We have a detailed explanation on our humidity page. Keeping the temperature at 65 degrees will lead to higher humidity. This temperature may require the use of a dehumidifier. I would also contact an HVAC company to evaluate your system. An air conditioning unit should lower the humidity in the home. Something is not working correctly.
Until the humidity problem is addressed, any cleaning procedures will only yield temporary results.
How do we clean this furniture? It's engineered wood.
The cleanup procedure is the same as regular wood, just ensure you do not use excessive amounts of water. I recommend damp wiping the surface instead of vacuuming. The latter tends to aerosolize the mold particles throughout the room. When damp wiping, use disposable paper towels and a basic detergent/cleaning solution. You don’t need to worry about the ability of the cleaner to ‘kill’ the mold, you’re goal is to physically remove it from the surface.
I live in VA but have been in MA for a few months taking care of my granddaughter. While it is cool in MA, it's still quite warm in VA. When my husband arrived home yesterday, he found mold on several pieces of furniture. The a/c was off and there has been a lot of rain there recently. I'm somewhat surprised at the problem although I understand why it happened (warm, stuffy, humid air with poor ventilation, PLUS we live on the water). The couch in the picture I attached will be tossed, as it wasn't expensive. However, the rest of the furnishings were more costly. My question is if it's worth trying to save any of the other pieces that are just beginning to show signs of affectation. Should I just clean house and start again, or try to get things under control. My granddaughter will be there over Christmas and I'm scared for her health.
The mold growth on the couch is pretty extensive. Your intuition is correct, this should be discarded. The ability to salvage the other furniture depends on the materials. If it’s hard, non-porous items like wood tables, cleaning is fairly easy and there’s little fear of lingering spores. If it’s upholstered, the cleaning is much more difficult. I recommend HEPA vacuuming the furniture outside (or at least in a garage). Even the best HEPA vacuums bypass a fairly large amount of spores into the air. After cleaning, you could have a local mold inspector collect an air sample while you gently agitate the furniture. This should give you a fairly good picture of whether you’ve removed the latent mold spores.
We were away this entire summer in Washington, DC, and found white powdery mold (or mildew, not sure) on the couch in our basement. We may have had some water damage from a bad rainstorm in the adjoining room. Any idea what this is, and how to treat it? Thank you.
This is very likely mold growth. If the couch is of low/moderate value, I would toss it out. In general, mold growth on porous items such as upholstered furniture is difficult to remove. If it’s worth a fair bit, you could attempt to salvage it via HEPA vacuuming. See the response to the previous photo/submission for details on the cleaning process.
I live in the low desert, no humidity in the home. Why do I have mold on my wood furniture?
Due to the low humidity in your environment, this growth likely occurred at the factory. After the wood is dried, the mold growth stops. What you’re seeing is the lingering staining from the prior growth. This is a fairly common issue with lumber and does not pose a health concern.