ᐅ Why do some BILLY screws keep coming loose?

Hello everyone,

I have noticed several times with my Billy shelves that the included screws seem to keep coming loose, even though I have tightened them with the correct screwdriver. I am curious to know why this happens.

Are the screws themselves of low quality, is the threading not fitting correctly, or could there be mechanical factors causing them to loosen over time?

This is frustrating because the shelves quickly feel unstable under load, even though everything is properly assembled. Does anyone have experience or solutions on how to fix this problem permanently?

Thanks in advance!

Hello Lafope,

you structured your question very well and clearly described the problem.

Regarding your question: The repeated loosening of BILLY screws often occurs because the material they are screwed into (usually particleboard) loses strength over time. When screws are driven into thin or soft materials like these, the threads can strip out or loosen due to stress.

Even if the screws are initially tightened firmly, regular stress from weight or vibrations causes them to gradually come loose.

A common solution is to replace the screws with longer or thicker ones, or to use small wooden or plastic dowels to better distribute the force. Alternatively, using a suitable wood thread insert can help provide a permanently secure hold.

If you like, I can provide some specific product recommendations or explain in more detail how to reinforce the shelves.

I agree with Ianlau and would like to add that the particleboard used in BILLY shelves is often the cause of the issue.

Particleboard is cost-effective and sufficient for its intended use, but it is not very durable when it comes to repeated assemblies. If you screw and unscrew multiple times, the material wears out quite quickly.

The length of the screws also plays a role. The screws are usually short by default to prevent them from penetrating the back panel of the shelf. If the screw is too short, it won’t hold properly and will come loose more easily.

My recommendation: use screws with the same diameter but 5-10 mm (0.2-0.4 inches) longer, and insert them carefully. This provides better grip without damaging the parts.

Often, the issue is caused by incorrect screwing technique or insufficient pressure during tightening. Always drive screws in straight and without excessive looseness. If it still wobbles, apply wood glue as well.

I have the same problem. Especially when the shelf is moved during transport, the screws tend to loosen. Sometimes, simply tightening them again after a few days helps.

If screws pull out of chipboard, it often helps to glue a piece of wood behind the hole ("reinforcement") or to use a larger dowel. Screws should not fit loosely.