Fitting wall units, finding fixings

I had a similar situation with a tv bracket, I found a plasterboard wall tv mount was the best. Can’t post a picture but might be worth looking at something like that.
Hope it helps

8mmwall plug with 5x100mm screws would be enough

It sounds like you have a challenging situation with your IKEA Enhet cupboards and the void behind them. You're right to be concerned about the strength of the screws you use because you'll want to ensure that the wall units are securely mounted, especially since they will hold storage items.

Here are some suggestions for your situation:

Use Wall Anchors: Since you're drilling into masonry, you can use wall anchors. These provide extra support and can handle heavier loads. Make sure to choose wall anchors that are compatible with masonry walls. Plastic or metal wall anchors can work well. Drill a hole into the masonry, insert the anchor, and then screw in your bolts.

Longer Bolts: If you can't find bolts with the right head and length combination, consider using longer bolts and cutting them down to size using a hacksaw or a bolt cutter. You can then file or grind the cut end smooth to fit through the keyhole washer.

Washer Modification: If you can't find suitable bolts, consider modifying the washer by enlarging the hole to accommodate a smaller-diameter bolt. You can use a metal file or a step drill bit to carefully widen the hole in the washer. Just ensure that the washer remains structurally sound after modification.

Consult with IKEA: IKEA's customer service may be able to provide guidance or suggest alternative solutions for your specific situation. They might have specific recommendations for attaching their products securely.

Professional Installation: If you're unsure about the right screws and anchors to use, or if you're uncomfortable making modifications, it may be worth consulting with a professional installer. They can assess your specific wall and cupboard setup and recommend the most secure installation method.

When selecting screws and anchors, consider the weight of the wall units and the items you plan to store in them. It's always better to overestimate the strength of the fasteners to ensure safety and stability.

Hi, as far as I remember, there’s a metal bracket that’s fixed onto the wall to support a wall unit. The plastic bits are there to adjust the height. In any case it’s advisable to follow the manufacturer instructions or get a qualified kitchen installer to do the job.