We live in an apartment built in the late 1920s. A few years ago, I mounted a lamp hook in the ceiling and remember being a bit puzzled by the ceiling, but didn't think much of it as it seemed to hold. In another part of the apartment, I used drywall anchors as there was a gap where it could expand, but not in this room. Since it held, everything seemed fine and the lamp has been hanging there for three years without any problems. However, we now have plans to switch to a really heavy ceiling lamp, and after some research, I've realized that we probably have a "kloasongtak" with reeds; a neighbor has found reeds in the walls. I want to review the attachment to feel secure, and I wanted to simply ask if anyone knows how thick the reed layer usually is. Surely, I must have hit a plank when I made the previous attachment? Currently, there's a reasonably large Moroccan metal lamp hanging there, and I can't imagine it would have stayed if the screw was only anchored in reeds and plaster. 
The reason I'm asking is that I'm abroad and have my eye on a lamp that will require a secure mount. Hopefully, it's just a matter of replacing the ceiling hook with a longer screw eye or something similar. It's possible that only part of the hook is in the plank today, and honestly, I don't remember how solid it felt when I put it up.
The reason I'm asking is that I'm abroad and have my eye on a lamp that will require a secure mount. Hopefully, it's just a matter of replacing the ceiling hook with a longer screw eye or something similar. It's possible that only part of the hook is in the plank today, and honestly, I don't remember how solid it felt when I put it up.Thank you for your responses, much appreciated! The lamp was purchased and is on its way in a huge package to Sweden. I'm back in Sweden myself and going out to get a sturdy screw eye!
Thank you very much! The picture is truly descriptive!T tergo said: