Build additional wall against existing wall for soundproofing

[JoeJoeJoe]

Hello,

My bedroom is wall-to-wall with the neighbor's bathroom and it's extremely noisy. I hear everything

It seems that there is a concrete wall and also a plasterboard between our apartments and maybe some insulation between concrete and plasterboard but not sure about that, however, it's not helping.

I did some research on byggahus.se and found the following solution that I might be able to build myself:
https://www.isover.se/solutions/it05-traregelinnervagg-ei60-55-db

Now the question is: should I build this wall directly onto the apartment floor and thus tear up parts of the laminate flooring or should I build the wall on top of the laminate flooring to get the best sound insulation against the neighbor on my side?

Additionally, it's quite noisy downward towards the neighbor below me too, and if you have any good tips on how to insulate downwards, it would be much appreciated as well. I've read about foam or foam and laminate on top, but I don't see many who have followed up on how it turned out afterward, so it's hard to know how much it helps.

Thank you in advance for all tips and your time.

 

[JoeJoeJoe]

Was the post too long or is there no one who has some input?
So TL;DR;
Should one build a soundproof wall on top of laminate flooring or directly on the apartment's concrete floor for the best soundproofing?

 

[ArneTW]

I would have built on top so that it can be easily restored.

A sound expert will probably show up eventually...

/ATW