We are building a duplex house, with one dwelling on the upper floor and another on the lower floor, and therefore we have extra soundproofing (partly in the joists, and partly under the floor with two chipboards with 19 mm Paroc step sound mat in between. The upper chipboard has been laid floating.
The tiler will apply leveling compound for the slope, arrange for the waterproofing, and install the tiles.
We have done the same in the bathroom, and the issue is that it has been questioned that it is floating in the bathroom and that we might encounter problems. The floor can move and the waterproofing may be damaged.
There is a 30 cm distance between the beams in the joists.
What should we do? Should we also screw the top chipboard? Of course, it is not possible to glue the top board as the step sound mat is in between.
Usually, you only have a 22 mm chipboard that you screw-glue (glue and screw, but remove the screws once it has dried?)
