Author Topic: stc adding  (Read 3333 times)


  • Guest
stc adding
« on: October 11, 2003, 04:37:25 AM »
when adding weight, it seems only a minor benefit is the result.

what about double walls and room in rooms, they have isolation working for them.

if noise enters:

passes through wall st 30

passes air gap...

passes through another wall stc 30

will this system be close to stc 60?

what if the same materials and mass were to be assembled on one wall, what would the stc difference be?

stc 20 difference = 4 times as quiet?



  • Guest
Re: stc adding
« Reply #1 on: October 13, 2003, 07:27:37 PM »

In soundproofing, you're always dealing with the law of "Diminishing returns". The means, for example,  that just because the Mass Loaded Vinyl (MLV) is a 26 STC if you double up on the (MLV) it will not necessarily give you a 52 STC, it will be more like a 45-47 STC. This is just the nature of soundproofing.
Now with the 2 separate walls of 30 STC each, you may get close to a 60 STC simply because of the dead air space between the two walls (this is provided that the dead air space is sealed and not just opened to the room itself).
There again, the same materials used in a separate wall would fall under the diminishing returns rule, because you are no longer dealing in the sealed ded air space.
A.J. I hope this has clarified STC system for you. I know it as clear as...mud... to me. Laughs. Thanks for your post.

Bob Orther
(The Bob Vila of Soundproofing)
Super Soundproofing Sales/Technical Associate.
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