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 back side of dresser.
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.
This is a picture of the bunk beds in my home. The exterior walls are made of concrete blocks. The house is a riverfront property but the house is more than 50 yards from the water. It is only about 1000 square feet. House has been closed about two months. I filed a claim with my insurance who had me pay for a company to come out and test for dampness. He said I had no water leaks and that the humid levels were normal. I bought a 50 pint dehumidifier and the relative humidity stays around 68 to 70 in the hallway. The company said this is “most likely not mold” which means we are doing our own clean up. I get a headache when I go in the house and we cannot live there. I can’t breath, can’t stop sweating, and get excruciating headaches. It is growing on all of the furniture, on the inside of the kitchen cabinets, on the wrought iron, on the cloth furniture, and even in the pool table. I bought a fogger machine and the mold and mildew liquid to put in it. We fogged from the top in the attic space to every room in the house. We are wiping all surfaces. I bought a mold kit from Lowe’s and will be sending it in to see what it really is that is growing in there. My grandson has asthma and just to go in to use the bathroom had him winded/sick. In your professional opinion, is this a type of mold? I am also allergic to mold, fungus, etc per the results of my environmental allergy test. It doesn’t make sense to keep paying for a house that we can’t live in. Oh, this house don’t have a crawl space. I can send additional pictures. Thanks for any help you can give.
This is almost certainly mold growth. Occasionally a white substance can occur due to efflorescence, but this only happens on masonry, concrete, etc. The widespread pattern of growth indicates high humidity throughout the room. This can be caused by poor ventilation, inadequate air conditioning or a flooding event. If there are no signs of a flooding event, it’s due to humidity. In regards to the insurance company’s claim the humidity levels are normal, this could simply be due to the timing of the inspection. It’s quite possible the growth occurred during a high humidity period but the levels had returned to normal the day the insurance adjuster visited the home. Mold growth will become inactive when the humidity/moisture levels return to normal, but the visible growth will not disappear.
Verifying whether or not the substance is mold growth can be accomplished with a simple tape lift sample. Any local inspector or lab should be able to accomplish this for a small fee.
Assuming the testing results come back positive, the extent of the growth warrants professional remediation/cleaning. The hard surface items, such as the wood bed frame, can be damp wiped with a mildicide. Porous items such as cloth furniture and the pool table will require HEPA vacuuming, and if unsuccessful, replacement.
My wardrobe is made of engineered wood and it has white powdery fungus. No matter how much I clean it off it keeps coming back. Any permanent solution to this??
The only permanent solution is to lower the relative humidity (FH). A mold resistant coating will eventually fail, due to the accumulation of dust on top of the coating. You’ll need to both monitor the RH and implement a solution decrease those levels.
Monitoring the RH, is relatively simple. Purchase an inexpensive RH gauge from your local hardware store or online. Place the device inside the wardrobe. Your goal is to keep it below 55%, and preferably, <50%.
Lowering the humidity is a bit more tricky. If you live in a humid climate, you’ll need either a dehumidifier or air conditioning. If you already have AC, hire a local technician to evaluate the system to ensure it is operating properly. If it’s working correctly, it should dramatically lower the humidity in the home.
If you don’t have air conditioning, a dehumidifier can help. However, they produce heat, which can be uncomfortable in a warm climate. If you live in a cool climate, the excess heat can help heat the room.
I found this on my couch in the basement. I’m planning to throw away the cheap furniture but the basement has carpet. I’m nervous about mold in the carpet. Thoughts? Should I have it cleaned? If so with what?
You are correct, this couch should be discarded. It’s very difficult to fully remove the mold growth from the upholstered furniture. This growth points to an overall problem of elevated humidity. I recommend purchasing a relative humidity gauge. Monitor the area and see if the RH rises above 55%. If it does, and I assume it will, you’ll need to lower the humidity.
In the winter months, you’ll need to focus on two items. First, increase the airflow to the basement. Stagnant air will lead to higher levels of moisture. This can be accomplished through a bathroom exhaust fan. If no fan is present in the basement, consider installing a Panasonic wall fan (WhisperWall).
Next, you’ll need to increase the temperature. As the temperature rises in the basement, the humidity will lower. The minimum temperature is determined by the target relative humidity. For example, if the RH is 65%, you’ll need to increase the heat until it drops below 55%.
There is mold on all of my furniture. What should I do? I am worried I am inhaling it as well.
This style of mold growth is nearly always due to excess humidity in the home. Your first step is to identify the cause of the elevated moisture. If this is occurring during the winter months, it’s due to poor ventilation. This can be remedied by increasing the rate of fresh air brought into the home. The least expensive technique is often to run the bathroom exhaust fan continuously.
Occasionally, the excess moisture is due to water vapor coming up from the floor, either from the crawlspace or concrete slab below. This can be ruled out by inspecting the crawlspace and ensuring a vapor barrier is in place. If the house is built on a concrete slab, use a moisture meter to identify if water vapor is moving upward into the flooring.
If the mold growth is occurring during the summer months, you’ll need to focus on your air conditioning system. In climates with hot, humid summers, the air conditioner is critical for removing excess humidity from the home.
Once cleaned, would putting a wood wax/varnish or seal help stop the mold from returning?
The coating will likely slow the recurrence of mold growth. However, if the source of moisture is not removed, the growth will eventually return. The only permanent prevention is to ensure the piece of furniture is stored in a location that remains under 55% relative humidity. Above this point mold growth can occur.
I found Mold on newly ordered IKEA sofa. Should I be concerned and return it?
Yes, I would return the furniture. This sometimes occurs during shipping and is certainly grounds for requesting a replacement.