Soundproofing house from 1940 - Replace sawdust with mineral wool?

[EllenR]

I have removed the original flooring in certain areas of my house from 1947 (different original layout, will be laying down equivalent plank flooring again).

Now I'm considering a bunch of "while we're at it" things, including whether to replace the sawdust with mineral wool due to very poor sound insulation between the floors. But is mineral wool better? Can it be supplemented with mineral wool up to the floor, or should air be left?

I know it doesn't help with impact noise.

 

[Du och 19till]

I would add more spån. I believe it dampens sound better than mineral wool since spån is heavier.

 

[EllenR]

I would add more wood shavings. I believe it dampens sound better than mineral wool. Since the shavings are heavier.

Thanks! So no air gap necessary?

 

[Workingclasshero]

With an air gap should be quieter.
/W