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Sound comparison: standard drywall, QuietRock, Green Glue

The Knock Test


REPOSTED FROM MY PREVIOUS BLOG:

By knocking on a wall,  you get some idea of how well dampened it might be for certain types of noise...or not.

I made a very short video demonstration in my own home to compare the audible differences between making an impact noise on normal, uninsulated gypsum drywall and two alternatives. The first example shows how it sounds to knock on a hollow piece of 1/2" gypsum board. This type of drywall is typical for mid-century American homes. 

Then compare it to:

1) a second layer of sheetrock glued on top of the original drywall with Green Glue in between the two layers -- no demolition required.

2) a layer of QuietRock 525 that replaced the existing layer of gypsum -- demolition required. Original 1/2" drywall was removed and fiberglass insulation was added before screwing the new QuietRock into the wall studs. One layer only. 
(NOTE from 2023: Now I know better, and I would have decoupled the drywall from the wall studs instead of screwing it in!)

Notice how "dead" the Green Glue wall and the QuietRock sound, compared to the original drywall!

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Comments

  1. Ryan W.December 23, 2010 at 6:47 AM

    looks like the volume of the sound is roughly proportionate to how hard you knock. : )

    ReplyDelete

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