How soundproof is cinderblock?

[onthaherb]

Lets say I built a room entirely out of cinderblock & motar. No openings, just a block room (no door) built on paved cement (standard dual cavity blocks).

Would I be able to hear two 6" maxfans if it was dead silent and I was standing right outside of it?

 

[hup234]

probably not ,if you solid fill the cavities,or go with styrofoam blocks,sound might travel through the ceiling...look up sound rated walls @usg.com

 

[the gnome]

insulation used for cinder block is vermiculite.
it was gret as far as sound goes.
mite be better out now, this was my exp. 20 yrs ago.
you can also add foam on the inside for better results.

music outlets now have material for drummers to sound proof their rooms, very effective, and very pricey too.
but it works