[salahesalem]

Hello

Cutting a hole to put in a single gang cable plate, and after cutting there piece of drywall out I'm seeing this green wall board behind it. Image attached. Trying to figure out what it is. I was thinking green board, but this is an interior wall in a townhouse and the wall is the living room wall, so I'm not so sure. It seems solid when I tap it with a hammer, so doesn't seem hollow behind it. Anyone have a clue as to what it is?

Thanks in advance.

 

[BayouRunner]

Looks like a sheet of waterproof sheetrock

 

[salahesalem]

Is that typical to find in a wall not in a bathroom or basement? And why double up at that point?

 

[joecaption]

What's on the other side of that wall?
If it's an ajoining unit your cutting into a party wall, a big no no.

 

[salahesalem]

Neighboring townhouse. Considering there are studs behind, indont see why going into it would be an issue, or much different from using studs to mount a TV or such

 

[joecaption]

Two main reasons it was done that way.
To stop sound from transfuring to the next unit.
And to contain a fire to a single unit.
I'm sure your HOA would be trilled with your idea.

 

[AllanJ]

Wasteful or overkill but maybe when the building was constructed there were some extra sheets of (more expensive) green drywall but no more gray drywall of the desired thickness handy.

Check your bylaws to see whether the apartment boundary (unit boundary) is the outer surface of the wall or against the studs. Usually you may not alter what is beyond your unit boundary without permission from the board of directors.

 

[joecaption]

That would be my guess also.
Same codes and principals and code apply.

 

[jlhaslip]

HOA rules aside, the Fire Rating on that wall is now violated.

 

[Tytryon]

Hello

Cutting a hole to put in a single gang cable plate, and after cutting there piece of drywall out I'm seeing this green wall board behind it. Image attached. Trying to figure out what it is. I was thinking green board, but this is an interior wall in a townhouse and the wall is the living room wall, so I'm not so sure. It seems solid when I tap it with a hammer, so doesn't seem hollow behind it. Anyone have a clue as to what it is?

Thanks in advance.

If it's a wall you share with another unit, the "green" board is 1/4" sound board to help with noise/vibration transfer.

A cheap but somewhat effective way to minimize noise.

 

[cuba_pete]

Is that typical to find in a wall not in a bathroom or basement? And why double up at that point?

Are you intentionally trying to cut a hole into your neighbor's bathroom wall...for...:vs_worry:

 

[FeelTheThunder]

It doesn't appear to be tight against the finish drywall. Sometimes cavities are filled with the scraps, this could just be a scrap piece of aquaboard with more scraps behind it filling the cavity.