Thanks for all the awesome posts, hopefully, it helps more than just me who is thinking the same!
So, for me, it will be like this I think: Nivell floor - Walls ON the Nivell floor with steel studs/steel tracks 45mm - Drywall with an air gap behind.
A few concluding questions:
1. Thinking about reinforcing the drywall wall with OSB boards behind it. Good idea? Is there anything better? There will be quite a bit of play down in this space and maybe a child might fall against the wall. Also, I would like to hang something on the wall, maybe as heavy as an LED TV.
When I built the interior wall between two bedrooms I put OSB behind it - my brother who is a carpenter thought it was good, precisely because they can handle pretty much anything. I put up a shelving system on the entire wall, so you can screw with "regular" screws, no need for drywall anchors or anything like that - it becomes much more stable that way!
