ᐅ Kallax has developed a persistent moldy odor after water exposure – what can be done?

Hello everyone,

I have a Kallax shelf from Ikea that unfortunately developed a persistent musty smell after water exposure. The shelf got wet a few weeks ago due to water leakage, and although I thoroughly dried it, the unpleasant odor remains.

I suspect that the fiberboard or particleboard inside absorbed moisture and now mold or mildew is causing the smell. I am particularly interested in methods to eliminate this musty odor permanently without having to replace the entire shelf.

Does anyone have practical experience with cleaning or treating furniture like this? Are there any recommended home remedies or professional products for these kinds of odors?

Thank you in advance for your help!

Hello,

regarding your issue with the musty smell after water contact on your Kallax shelf:

The cause is likely the penetrating moisture that cannot fully evaporate, as particleboard absorbs water deeply and dries very slowly. This creates favorable conditions for mold or bacterial decay, which causes the musty odor.

My recommendations:

1. Place the shelf in a well-ventilated and warm location, ideally with low humidity.
2. Wipe surfaces and inner sides with a mild mold remover or a vinegar-water solution (1:1). Vinegar has antibacterial properties.
3. Put activated charcoal or baking soda in bowls next to the shelf to absorb odors.
4. Consider using an air-dry system or moisture-absorbing granules.

If the odor persists, sealing the wood with a special varnish can help reduce moisture absorption.

Best regards.

Fitigu schrieb:
Cleaning or treatment of such furniture

I wonder if treating with a vinegar-water mixture is truly effective when moisture has penetrated deep into the material. Vinegar does kill bacteria on the surface, but does it penetrate deeply enough?

Have you or other users had any experience showing whether simply wiping it off provides a lasting solution? Or is the problem within the material itself, requiring internal treatment or replacement? Otherwise, it seems like a temporary fix.

I completely understand the issue with the musty smell—I’ve been annoyed by it myself. It can be very frustrating when furniture develops a persistent odor after just one exposure to moisture.

My advice: patience is key. If you place the shelf in a warm, dry spot and ensure proper air circulation, the smell can fade over time.

If you have pets or sensitive allergy sufferers in the house, I wouldn’t underestimate the musty odor, as it often indicates spores that can be relevant to health. In such cases, it’s better to replace the furniture or have it professionally cleaned.

Don’t feel bad if it’s not easy to get rid of the smell—these materials are sensitive to moisture.

Regarding the musty smell from water damage on Kallax-style particleboard shelves, I can share the following after thorough research:

The carcass panels are usually coated with melamine, which is somewhat water-resistant, but the edges and especially the drilled holes are unsealed, allowing liquid to penetrate deeply. This seeps into the fiberboard, causing swelling, mold growth, and, consequently, a musty odor.

My experience:

1) Completely empty the shelf and ventilate well for several days at 20-25°C (68-77°F) using a dehumidifier and a fan.
2) Use a wood preservative that kills mold spores, but apply it sparingly on melamine surfaces to avoid damaging the finish.
3) For areas with particularly strong odors, wiping with a mixture of ethanol (denatured alcohol) and water can help, as it evaporates quickly and kills fungi.
4) Seal the visible edges and drill holes with waterproof varnish or a special edge sealant to prevent new moisture ingress.

Question for you: How long ago did the water contact occur, and how thoroughly was the shelf dried before? This greatly affects how deeply the moisture may have penetrated.

kulau schrieb:
Question for you: How long ago was the water contact, and how thoroughly was the shelf dried afterward?

Thank you for the detailed response. The water contact happened about 3 weeks ago when I accidentally knocked over a vase. The water remained on the surface for around 30 minutes and partially dripped through the holes at the back into the interior. I immediately cleared the shelf, dried it completely using a hairdryer (only on the cool setting), and then left it in a very well-ventilated room for an additional 3 days.

Nevertheless, it has smelled musty ever since, especially when getting closer to the edges. The shelf is located in my kitchen, which is relatively warm, but there is no extra air dehumidification.

So far, I haven’t been able to see any visible mold — however, the smell strongly suggests its presence.