soundproofing mezzanine floor

Hi,

I want to sound proof my mezzanine floor from the (rented) room below. I have read a load of threads on this and decided that I will use soundblock PB on the ceiling below (maybe 2 layers), acoustic rock wool 100mm between joists. osb, then acoustic pb then acoustic mat then floating glued t and g plywood above.

I realise this isn't the ultimate solution, but should be fine for my situation as the mezzanine is only really a sleeping platform.

My question is about the OSB. its purpose is just to support the acoustic pb above the joists. How thin could this board be? There is a UB section in the middle of the platform which sticks up 9mm from the top of the floor joists. Would 9mm OSB be sufficient to stop the PB from breaking?

many thanks,

John.

9 mm will fit the protruding beam but will not provide, or in anyway help with the acoustics. Accoustic fiber sound block boards might be a better idea, although if my memory serves, I think it is a 1/2" board?...pinenot

Thanks for your response pinenot.

I was really just wondering if the osb at that thickness would do enough to support the acoustic pb above it, ie spreading the narrow loading of the joists, but I think I'll just play it safe for the sake of a few mm and use 18mm.

thanks again.