ᐅ Reinforcing KALLAX Shelves with Metal Strips – How to Install?

Hello everyone,

I am planning to reinforce my KALLAX shelves from the IKEA system with metal strips because I want to store somewhat heavier items on them and reduce the sagging of the original shelves. My specific question is: What is the best way to attach the metal strips so that they are securely fixed without causing damage to the shelves or the shelving unit?

I have considered drilling or screwing them in myself, but I am unsure whether this might negatively affect the material structure or if there are more elegant solutions. I am also interested in what type of metal strips work well (aluminum, steel, flat or L-profile) and whether I need washers or special screws.

Who has experience with this or can provide a step-by-step guide? Thanks in advance!

I recommend using aluminum L-profiles and attaching them to the underside of the shelves with small wood screws. Pre-drilling before screwing is important to prevent the wood from splitting. The screws should not be too long, as they could damage the base panel.

Hello,

to effectively reinforce your KALLAX shelves, metal strips are a good option. It is important to attach the strips to the underside to avoid interfering with the visible surface. For the material, aluminum is recommended due to its weight and good strength. Steel would be stronger but also heavier and more difficult to work with.

To prevent damage, you should definitely pre-drill using a drill bit slightly smaller than the screw diameter. This helps avoid splitting. Flat-head or countersunk screws work better because they sit flush and don’t protrude from the shelf bottom.

A small tip: use washers if the screws don’t grip well or if the wood is too soft. Also, make sure to buy metal strips longer than the width of the shelves so they support well on both sides.

If you like, I can send you a list of recommended screws and matching drill sizes.

Metal strips are best screwed from underneath with countersunk screws. Pre-drill holes to prevent the MDF wood-based panel from splintering. Use a drill bit of 3-4 mm (approximately 1/8 inch), depending on the screw. I usually use aluminum profiles, as they are lighter.

A note on stability: The KALLAX shelves are made of medium-density fiberboard (MDF), which is quite sensitive to point loads. Metal strips should therefore be supported across their full width to distribute the load evenly.

When assembling, I recommend fastening the strips not only in the center but also at the ends to prevent bending. Drill holes carefully using the appropriate drill bit to avoid cracking.

If screwing directly into the MDF, use screws with coarse threads that grip well without pre-drilling, although pre-drilling ensures cleaner results. Washers help prevent pull-through. For those who prefer not to use screws, there are also special clips or brackets that can be inserted without drilling.

PeoDaniel schrieb:
It is important to attach the strips on the underside to avoid disrupting the visible surface.

Thanks for the tip about positioning. Should I attach the metal strips along the entire length of the shelf board, or are sections in the middle sufficient? Would there be enough stability if only about 2-3 strips are mounted parallel to the depth?

Furthermore: If I fix the strips with screws, would additional wood glue be advisable or rather overkill?