50mm or 75mm

HI.. one quick question. How much difference would the STC and TL be if i had a double 13mm gypsumboard wall construction on 45x95mm woodstuds, if i put 50mm pcf insulation or 75mm??? Will there be any other advantage/disadvantage?? Thanks... Andy

Can you detail the construction more? For example; single frame, single with Resilient mounting one side, Staggered studs with common caps and plates, double frames with wallboard only on the outside of each frame, etc - If you can't do a sketch, just list each component of the total wall, starting at one finished surface and travelling through the wall to the OTHER finished surface... Steve

construction look like this: the orange is ofcourse the insulation in question.. 50 or 75mm??

whoops.. .the walls are ofcourse gonna be turned the other way FROM eachother.. but i gues you figured that out =)

Yeah, I thought you were building some of John's "inside out" walls :? Here's a link that should help you - http://www.johnlsayers.com/phpBB2/viewtopic.php?t=2154