ᐅ Tip for a stable combination of multiple KALLAX shelving units?

Hello everyone,

I am currently planning to combine several IKEA KALLAX shelves side by side or stacked, but I definitely want to avoid the structure becoming shaky or unstable. My question to experienced KALLAX users here is:

Is there a proven trick or method to securely and firmly connect multiple KALLAX units? Especially when stacking or placing them side by side, the individual modules tend to tilt or wobble slightly. I would appreciate specific tips for stabilization, for example, which types of fasteners you use, whether special connectors are helpful, or how you handle arranging the shelves vertically or horizontally.

Thank you in advance for your detailed advice!

kajon schrieb:
Is there a reliable trick or method to securely and firmly connect multiple KALLAX shelves together?

Hey kajon, it’s great that you want to combine several KALLAX units! 🙂

My advice: definitely connect the shelves using metal brackets that you screw on the inside at the back. That works really well! Also, make sure to attach the units to the wall – this is essential to prevent any wobbling! I used furniture anchors for that; they are very sturdy and easy to install.

If the units are stacked vertically, it’s best to also screw through the top panel into both modules to firmly join them. Then they won’t wobble at all. This is a really effective solution and makes using them much easier!

GAGRAHAM schrieb:
Be sure to connect the shelves with metal brackets screwed on the inside at the back.

That’s a good start, and I’d like to add some points. The stability of KALLAX shelving units mainly depends on properly connecting the individual modules and securely anchoring them to the wall. Here is a detailed approach:

1. First, I recommend using flat brackets (also called furniture brackets) when combining the shelves. Screw these onto the adjacent side panels of the modules so they cannot move relative to each other.

2. For additional stabilization between vertically stacked KALLAX units, it’s advisable to insert screws with wall plugs (dowels) through the threaded holes in the top panel and bottom cover. This will create a very firm connection that prevents tipping.

3. The back panel of the shelves usually consists of a thin fiberboard. While this provides some stability, it typically won’t be sufficient for multiple modules, especially if the shelves are loaded.

4. Therefore, it is absolutely necessary to install extra wall fixings. I recommend special furniture anchors or, if possible, hooks with wall plugs that are directly screwed into the wall.

5. Minor unevenness in the floor can be compensated for by placing furniture pads under the feet. Otherwise, even small floor irregularities can encourage tipping.

One more question: What kind of surface will you place the shelves on exactly? Hard floors or carpet? This can influence the choice of securing methods.

I completely understand that you’re looking for a secure solution, as unstable furniture can be very stressful.

kibutar schrieb:
That’s why it’s absolutely necessary to install additional wall anchors.

I agree with that. No matter how many brackets or screws you use between the shelves, without wall anchors they can easily tip over, especially if there are children or pets in the home.

What I’ve also tried myself is placing thin anti-slip mats between the shelving units and the wall. This helps prevent the units from shifting if wall anchors aren’t an option.

At the same time, I would make sure to place the shelves on a level surface, otherwise they will wobble. I hope this helps you a bit.

kibutar schrieb:
1. First, I recommend using flat brackets (also called furniture brackets). 2. Install screws with wall plugs. 4. Add additional wall mounting.

These traditional recommendations sound reasonable but mainly focus on structural stability. I want to take it a step further and point out that when using multiple KALLAX units, the load distribution may not be optimal.

This means: relying solely on brackets and screws might lead to what is called resonance susceptibility, which can cause wobbling, for example, with doors or heavy items.

So, my theoretical recommendation is: in addition to connecting the units with brackets, consider whether adding cross braces or a panel could stiffen the entire structure. Especially for taller stacked units, a solid base panel at the connection level can work wonders.

I’m curious if anyone has already implemented such ideas or alternative approaches in practice?

Connect all modules using brackets.
Then secure the shelves to the wall.
Level the feet with washers.
Done.