I live in a furnished attic in a multi-family house from 1910. The floor structure to the floor below consists (at least) of 30-40 gravel and sand (with transverse thick beams that extend between the outer walls), on top of this a layer of boards, then bricks. On top of this, a layer of sand on which chipboard panels have been laid floating (with masonite/or chipboard pieces between the joints). I realize that the chipboard panels probably lie floating for soundproofing reasons.
The floor has become uneven, probably because the sand has shifted in connection with the builders needing to dig holes in some places that were then filled in.
My builder now suggests that the floor be stabilized with a wooden framework with sand between the beams where chipboard panels are then laid on the beams/sand.
I am concerned that this might be a problem with sound insulation downwards, should I be, or should all the mass of stone and sand under the bricks be sufficient to insulate against impact and other noise?
