ᐅ Kallax out of level after laminate flooring installation – how to fix it?

I would like to add a structured solution that I often use myself for furniture on uneven floors. The goal is to proceed step by step in a systematic way:

Step 1: Check the floor
- Use a spirit level, ideally a digital precision tool or a laser level, to accurately determine the unevenness.

Step 2: Inspect the furniture feet
- Check if the original feet of the Kallax are replaceable. If so, get adjustable furniture feet with a thread length of about 2-3cm (1-1¼ inches) to allow enough adjustment range.

Step 3: Gather leveling materials
- For minor unevenness, plastic or felt leveling wedges that can be stuck or placed under the feet are suitable.
- For larger differences, small wooden wedges, carefully cut to size, are an inexpensive option.

Step 4: Installation and adjustment
- Attach the new feet and make rough adjustments.
- Position the shelf unit at its intended location and check the level with the spirit level.
- Add wedges as needed for precise fine-tuning.

Step 5: Check stability
- Make sure the shelf does not wobble under load.
- Non-slip pads or furniture stoppers are helpful to prevent sideways movement.

Summary: Often, a combination of adjustable furniture feet plus fine-tuning with wedges is sufficient. Install the feet first and add wedges if necessary.

This method is reversible and rarely causes damage to the floor or furniture. I hope this guide helps you!

Domebla schrieb:
The idea with the OSB board sounds interesting.

Regarding the OSB board: If you choose this approach, I recommend using a thin board, ideally between 6-10 mm (1/4-3/8 inch). Thicker boards are more stable but increase the overall build height and can cause problems later when fitting doors or baseboards.

It is also important to treat the board's surface properly—a sealant will protect against moisture and make cleaning easier.

For height adjustment, small wooden shims can be placed under the board. Alternatively, threaded adjustable furniture legs as supports under the board provide a precise and final level adjustment system.

In my opinion, a combination of both solutions (OSB board plus adjustable feet) is the most robust. This creates a flat, load-bearing base without unwanted stress on the shelving.

If the floor is not extremely uneven, you don’t need complex substructures; feet or shims will suffice.

I can definitely relate to the feeling when a shelf wobbles, as it personally annoys me too. Especially with a popular piece of furniture like Kallax, which I use several times myself, you naturally want it to stand stable and secure without creaking or wobbling.

Besides the technical tips, I just want to reassure you: It is completely normal for laminate flooring not to be perfectly even, especially in older buildings or with minor unevenness in the floor. So you are not alone with this issue!

What I’ve learned is that small wedges or felt pads often provide a lasting solution, especially when the furniture is only slightly uneven. And if the differences are larger, a stable base or adjustable feet really make sense.

Don’t worry, you’ll definitely find a solution for your Kallax that you feel comfortable with in the end and that is durable. 🙂

Tevin schrieb:
Many users have successfully used height-adjustable furniture feet on Ikea shelves like the Kallax.

Thanks for the tip, I immediately checked at a hardware store for height-adjustable furniture feet in the right size. This really seems like a straightforward solution. Also affordable, and above all reversible.

rubybi schrieb:
Furniture feet with a thread length of about 2–3 cm (1 inch), so you have enough adjustment range.

Sounds good – I assume this means I can adjust the height with millimeter precision? Another important point for me: Are there differences in the load capacity of these feet? My shelf will definitely hold several books, so it will be relatively heavy.

I would appreciate if someone with experience could share how stable this solution is in everyday use. Do the feet stay firmly set for a long time, or do they tend to move again?

Thanks again for the advice so far.

Domebla schrieb:
Are there differences in the load capacity of the feet?

Yes, definitely: furniture threaded feet come in various materials and quality levels. Inexpensive plastic threaded feet or simple plastic bases often support only up to 15-20 kg (33-44 lbs) per foot. Steel feet or those with metal threads can carry significantly more weight—often 30-50 kg (66-110 lbs) or more per foot.

Since your Kallax shelf will be loaded with books that can quickly add several kilograms per shelf, I recommend using more robust metal threaded feet. These also provide better long-term stability, so the adjustment usually stays well maintained.

In addition, high-quality models often feature rubberized bases to minimize slipping.

If you like, I can also share manufacturers or suppliers that have proven reliable for such purposes.

I would like to add a point to the discussion that is often underestimated:

When installing and adjusting height-adjustable feet, it is important to secure the shelving unit on a solid surface to prevent shear forces or lateral movement.

If the shelving wobbles due to side-to-side rocking, using additional wall fixings or angle brackets to secure it to the wall can help. This is especially important for tall shelving units, not only for stability but also for safety.

Although it may require more effort, balancing the shelving using height-adjustable feet can be combined with wall fixings to achieve optimized stability.

Finally: leveling out uneven floors should be done with the goal of avoiding tension within the shelving (no twisting of the frame), as material deformation over time can lead to damage.