From what I remember just putting insulation between the joists isn't going to block much sound from escaping since it only affects the highest frequencies. Putting insulation in then a couple of layers of drywall on top would help with a wider range of frequencies.

Unfortunately the things you do to stop sound from escaping the room are often not the changes you would make to improve sound WITHIN the room (ie bare insulation in the ceiling probably WOULD help the sound inside your theater by damping reflections off the ceiling).

Here are a couple of useful links on wall construction -- I imagine the same works for ceilings. The isolation clips sound interesting; don't know anything about them though :

http://www.audioasylum.com/forums/rives/messages/2378.html

http://www.audioasylum.com/forums/rives/messages/2365.html

Shouldn't affect room temperature very much, I imagine... you probably have some kind of impermeable floor covering on the top of the joists anyways ?

Last edited by bridgman; 07/18/05 01:49 PM.
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