Re: blown cellulose for sound proofing

That's typically how it's done - drill holes at the top and use the
smaller nozzle to blow the cellulose into the wall. It'll probably
help deaden the noise, but bear in mind that it does settle over time
so you might notice the sound gradually getting louder again. Also,
interior walls may not be sealed as tightly as exterior walls so you're
going to get dust leaking into the two rooms from any holes like
fixtures, outlet boxes, switch boxes, under the baseboard molding, etc.
while you blow it in. Once you're done blowing it in, the dust should
settle down.

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