How to soundproof receptacles?

[kiwiaudionut]

I'm retrofitting an existing room to use as a HT room and still do not have a firm plan to soundproof the existing 110V receptacles. I'm GreenGluing 5/8" drywall and affixing it to the existing drywall. I can access the back of two of them, because the back of that wall is still open and so can box them in easily. But the others are a problem. 3 of them are shallow boxes in a furring stripped drywall roughly 3/4" from the concrete wall behind them !

I'm seriously considering eliminating the problem ones altogether - after all, I'm not going to need them in a home theater for any reason I can figure!
Unless a good sealing method pops up, I believe I'll be doing that !!

Eliminating receptacles just goes against my remodelling brain though, you know!

Any ideas?

 

[mtrycrafts]

I'm retrofitting an existing room to use as a HT room and still do not have a firm plan to soundproof the existing 110V receptacles. I'm GreenGluing 5/8" drywall and affixing it to the existing drywall. I can access the back of two of them, because the back of that wall is still open and so can box them in easily. But the others are a problem. 3 of them are shallow boxes in a furring stripped drywall roughly 3/4" from the concrete wall behind them !

I'm seriously considering eliminating the problem ones altogether - after all, I'm not going to need them in a home theater for any reason I can figure!
Unless a good sealing method pops up, I believe I'll be doing that !!

Eliminating receptacles just goes against my remodelling brain though, you know!

Any ideas?

When I built the house I got some boxes from a Canadian company that has a flange with seals so it prevents aid past the opening and drywall, and had seals where the wires pulled into it.
Or, just stuff a lot of insulation around the back and don't place the HT outlets in a cavity that has one already in the other space on the other side of that wall. Any leak will not be passed into that room.

Here you go; I found the box doing storage duty in the garage

http://www.tnb.com/contractor/docs/nutek.pdf

Scroll down and look for the Air Tight models.

 

[Johnd]

Stuffing insulation around a box will result in poor sound insulation. I would use expanding foam about the back, sides, top and bottom. In new construction this is achieved quite easily. It's not too dificult with a remodel box though: have the box and wiring prepared to set, spray in some low expanding foam about the entire cavity, install the box, and set the wings quickly...because you'll never be able to release the wings. It will be glued in place. But you also have a "tight" penetration. I would also consider using a shallow box so as to afford more insulation and less of a hollow cavity in the wall.

 

[Davemcc]

I'm seriously considering eliminating the problem ones altogether - after all, I'm not going to need them in a home theater for any reason I can figure!

That might be against building codes, hard to say if it is where you live. If you have to have an inspection done, you might want to check.

Edit - I see you live in Findlay. I've been there to play Rugby.

 

[kiwiaudionut]

Theres no building codes here Dave, so I can do what I want, but there are a couple of bad rugby teams !
Just kidding - my son plays on one of them. Played a bit myself back in the old country!

Some good ideas here. Thanks guys.

 

[Rickster71]

I wouldn't eliminate any receptacles. If the work is being inspected, it won't pass code.
Also, if you plan to sell in the future, you may not get a CO if the receptacles aren't at 12' Max spacing.

If some of the receptacles are going to end up behind a couch, or other furniture; it may not be as critical.

 

[Johnd]

I wouldn't eliminate any receptacles. If the work is being inspected, it won't pass code.
Also, if you plan to sell in the future, you may not get a CO if the receptacles aren't at 12' Max spacing.

If some of the receptacles are going to end up behind a couch, or other furniture; it may not be as critical.

Well, since we're discussing codes now, I'll go one further than that. Since you've now opened up the wall, per Nec code, the 6-12 rule applies (6' from corners and doorways/openings, and 12' on a wall): other than in kithcens, bathrooms, closets, hallways, etc., where other rules apply, of course.

Oh. No codes? Well then, nevermind.

 

[Rickster71]

Theres no building codes here Dave, so I can do what I want,

How does it work out that you don't have building codes?
The electrical code is national.

 

[Johnd]

How does it work out that you don't have building codes?
The electrical code is national.

How is it you always ask the really tough questions?!

 

[kiwiaudionut]

I wonder if I should cut out the section of drywall with a receptacle in it, seal up the box from behind, then refit and repair the drywall. I haven't yet added the second drywall/GreenGlue layer yet, so this is feasable !

Found these items called putty pads, but again rear access is necessary !

What to do if one cannot access the rear? Heard a tip that uses spring loaded outdoor weatherproof covers - ugly but Hmmm !!

 

[Alex2507]

There is an item available at Home Depot that goes behind the cover plate. It is a relatively thin rubber foam that is arguably of limited benefit but it does seal the cover plate. As mtry mentioned, not having dual outlets in stud bay going to opposite sides of the wall really helps. And as a few have mentioned, codes are everywhere. In Florida my dog house had codes. No joke.

 

[kiwiaudionut]

Yes, I was going to use those anyway Alex, but I don't believe they'll get the whole job done. One plus is that I only have the one area with a back to back problem and that is the switch inside the door. I think I'll tear into that wall and putty pad the back of those switches. The rest I think I'll seal up as best I can inside and around the box with foam and/or silicone, slap that foam gasket on there and see how it is.

 

[Alex2507]

Careful with that foam stuff. That expanding business has caused windows and doors to never shut properly again. That's the one in the yellow can labeled "Great Stuff". There is one in a blue can just for doors and windows. If your dual boxes in one stud bay are at way different heights then you should be fine as the sound would have to go through a couple of feet worth of insulation to get out.

 

[kiwiaudionut]

Yes, that foam stuff is incredible. I filled a small cavity above a window before and it blew the drywall off the wall ! It expands so much more than you would expect and is strong!

 

[kiwiaudionut]

Problem solved !

Just in case anyone else comes across this problem, I have found a solution.
I cut the drywall surrounding the box at the stud lines and siliconed all around the box openings where the wires come out etc. I found a cheaper alternative to "putty pads" which were $50 for 10 sheets 4" x 8".

At my local Menards store I found a product called "Protecto Dual Guard Threshold tape" for $10 (5.5" x 6.5 feet roll) I removed the sticky back tape and moulded this around the back of the receptacle box and to the stud and drywall, then caulked any gaps.
Then refit the drywall piece and repair as you normally would.
I then installed the next drywall layer with Green Glue and on to the next one !

I hope this helps someone else that is unsure about how to seal receptacles.
Picture below shows one that I was able to attack from the rear !

 

[Exit]

I have used caulk with a caulking gun to seal the space between the electrical boxes and the drywall. I did this mostly to stop some drafts and save energy. I don't know if this helps acoustically. Maybe you could do the same thing with green glue.

 

[mtrycrafts]

I have used caulk with a caulking gun to seal the space between the electrical boxes and the drywall. I did this mostly to stop some drafts and save energy. I don't know if this helps acoustically. Maybe you could do the same thing with green glue.

Sure it helps. With air leaks you also carry the acoustic power into another room if that has a connection through that air passage.
Just like heating vents can do.

 

[mperfct]

I have used caulk with a caulking gun to seal the space between the electrical boxes and the drywall. I did this mostly to stop some drafts and save energy. I don't know if this helps acoustically. Maybe you could do the same thing with green glue.

You'd be wasting your money if you use green glue. Just use a 50-year/acoustical caulk and you should be fine. GG is not a substitute for caulk, even though it comes in caulk tubes.

 

[mperfct]

FF 6 months...

I used the putty pads in my theater and they seem to work great. They are pretty stinky, but very easy to work with and seem dense enough that they would do the job we need them too.

Two thumbs up.

Also, don't buy as much as you think you need. I way overestimated and have 50% or so leftover.