ᐅ My Kallax unit frequently loses screws when the humidity is high.

Hello everyone,

I have a rather unusual problem with my Kallax shelf from IKEA: the screws keep loosening whenever there is high humidity, and I have to constantly tighten or even completely replace them. This is really frustrating because the shelf should be very stable, and normally these kinds of issues shouldn’t occur.

Has anyone experienced similar problems? Specifically, I’m interested in whether certain types of screws, pre-tensioning methods, or preventive measures can help with moisture exposure. I live in an area with typical summer humidity, and it seems like the wood swells or deforms somehow, causing the screws not to hold properly anymore.

Looking forward to your tips and explanations! Maybe there’s a simple trick that can solve this problem permanently.

Thanks in advance!

setra schrieb:
With high humidity, the screws keep coming loose

I know that problem all too well! ? My advice: definitely use threadlocker! It works great, even when the wood expands and contracts. Just apply a little threadlocker to the threads before screwing them in – then nothing will come loose!

It’s amazing how much a simple drop of adhesive can help! :-)

Also, check if the screws are exactly the right ones for the Kallax; sometimes replacement screws don’t fit properly and end up loose.

Try wrapping the screws with a rubber band before driving them in. This increases their grip in the hole.

Alternatively, use longer screws that engage more wood.

setra schrieb:
This is really driving me crazy

Oh yes, these issues can be truly frustrating—I know the problem with wood and high humidity all too well! 😅

Here’s a tip from me: how about using small felt or cork pads at the contact points so the wood doesn’t sit directly on a damp surface? Less moisture on the shelf means less warping and swelling—basically a mini protective barrier against “wood tantrums.” 😉

And of course, threadlocker is essential. But it’s great that you’re paying such close attention—many don’t realize the actual problem is the wood, not the screw.

Interesting that everyone here immediately recommends threadlocker. But thinking critically – maybe it’s actually a design issue with the Kallax?

Wood naturally expands and contracts, and if the design isn’t made to handle fluctuating humidity levels, nothing fundamental can be changed without modifying the system itself.

Threadlocker only adheres to the surface; the long-term problem of warping parts remains.

My provocative thesis: If you live in a humid climate, you might want to avoid a material or furniture that is so sensitive to moisture.

theota schrieb:
Threadlocker only sticks to the surface

I have to disagree. Threadlocker can help by compensating for vibrations and light loads.

But what’s really important is properly pre-drilling the screw holes. If the hole is too large, no screw will hold—no matter how much adhesive you use.

Also, you should check whether your Kallax is standing completely dry and well-ventilated. Damp air alone isn’t the issue; continuous moisture on the wood significantly changes its structure. A dehumidifier can work wonders here.

It would also be interesting to measure the wood moisture at different times of the day.