Ideas for mounting a 4" electrical box

[Dan5602896]

Hello,
I'm installing (new construction) 2, 220v outlets and a switch for my compressor. I need to use 4" boxes. I have not found any with mounts that are offset for sheetrock like a standard outlet box.

So, I would like to know what others do to use a 4" box such that the cover for the box is flush to the surface of the sheet rock.

 

[Aceman]

You want a 4 sq deep bracket box with a mud(plaster ring). You can google it to see what it looks like. Mud rings are sold seperately to match drywall thickness. For instance, they come in depths like 1/2, 5/8, 3/4, etc.

 

[Norcal]

You want a 4 sq deep bracket box with a mud(plaster ring). You can google it to see what it looks like. Mud rings are sold seperately to match drywall thickness. For instance, they come in depths like 1/2, 5/8, 3/4, etc.

Use a 1/2" for 3/8" thick drywall, 5/8" for 1/2", and 3/4" for 5/8" and the ring will be flush w/ the finished surface, this is very important for preventing "floating" receptacles, otherwise they will be 1/8" below the finished surface.

 

[Dan5602896]

Can I use a single riser like the picture, as I'm using #8 wire with a 30 amp switch and 2, flush mount outlets, or do they make covers for the switch and outlets that then cover a mud ring that is punched for both a single or double gang?

The 4th box is to run the wire to the compressor from the switch. If I use a mud ring, is there a cover that lets me attach the conduit?

Thanks to all for your help.

 

[mrb]

im a bit confused by your question. a cover that lets you attach the conduit? Is this from the box to your compressor? If that is the case, then yes just use a single gang mud ring, then a blank cover with a 1/2" knockout in it.

please explain "2, flush mount outlets, or do they make covers for the switch and outlets that then cover a mud ring that is punched for both a single or double gang?"

also, how many HP is your compressor?

 

[babzog]

Hello,
I'm installing (new construction) 2, 220v outlets and a switch for my compressor. I need to use 4" boxes. I have not found any with mounts that are offset for sheetrock like a standard outlet box.

So, I would like to know what others do to use a 4" box such that the cover for the box is flush to the surface of the sheet rock.

2x4 block between the studs, set back sufficiently to allow the box to stand proud of the studs by an amount roughly equal to the thickness of your finishing material. If it's a little bit recessed into the wall, that's okay, it's easier to deal with that then if the box protrudes past the wall surface.

Then, just screw the box to the 2x4 with a couple of screws and that sucker isn't going anywhere.

 

[kbs2244]

What babzog said, but I use a pice of plywood.

 

[Dan5602896]

im a bit confused by your question. a cover that lets you attach the conduit? Is this from the box to your compressor? If that is the case, then yes just use a single gang mud ring, then a blank cover with a 1/2" knockout in it.

please explain "2, flush mount outlets, or do they make covers for the switch and outlets that then cover a mud ring that is punched for both a single or double gang?"

also, how many HP is your compressor?

Yes, from the compressor to the box. I am using 2 boxes for the compressor. One to receive the feed to the switch, then to the 2nd box to the compressor. #8 wire is required for my compressor per manual. 5 hp.

Below is an example of a flush mounted outlet. The mud rings I've seen, are like the one in the prior picture or the ones that are a double gang. If I use the double, I want to make sure there is a cover for it and the outlet and switch.

 

[Dan5602896]

2x4 block between the studs, set back sufficiently to allow the box to stand proud of the studs by an amount roughly equal to the thickness of your finishing material. If it's a little bit recessed into the wall, that's okay, it's easier to deal with that then if the box protrudes past the wall surface.

Then, just screw the box to the 2x4 with a couple of screws and that sucker isn't going anywhere.

Simple, I like it. Duh! Thank you.

 

[MrMark]

That outlet fits best in a two gang box.

You are not going to try to jam a switch and that outlet in a single box, are you?

The 2X4 backing is a great idea. The mounting flange on the boxes is somewhat flimsy and for rough service they move around some. I wish I had used the 2X4 backing. I hate how flimsy those mounting brackets are.

 

[MrMark]

OK, I think I see what you are doing. Yeah, there are covers.