In message , Scabbydug
writes
Hoping you can help.Mikie

This
http://en.wikipedia.org/wiki/Sound_transmission_class

Should start you off in the right direction.

Not knowing where you are in the world it would be difficult to offer
better advice as different countries stock different materials etc

On the basis that this newsgroup is 'uk.d-i-y' maybe we should in all cases
assume the poster is in the UK ....:0)

Experience has shown that you really can't make that assumption


--
geoff