In a guest apartment with three rooms the smallest room has two layers of sheet flooring in it. Below the two layers there's some sort of black felt paper. All those layers are glued onto each other and they are not tiles but one big sheet each.
The flooring jobs were done poorly, with the surface showing up to one third of an inch difference in height over maybe a yard distance and many small bubbles and spikes. The flooring was tested, the middle layer contains asbestos.
Now we'd like to put hardwood flooring in, avoiding removal of the existing floor since it contains asbestos. I have just the right amount of click type bamboo flooring (suitable for below grade) with 3mm thick underlayment and would like to use that.
My question is essentially what do I use best to make the existing floor level? Can I pour regular leveling compound over it? I'm afraid that it will be too thin and crumble over time. If I make it thicker, there will be a height distance to the other rooms. Is there some special leveling compound suitable for this situation (thin and over vinyl flooring)?