Plastic versus metal recep/switch boxes

[W-Cummins]

"The one reason I HATE the light weight blue boxes has nothing to do with any electrical requirements. I hate them because I like to use a roto-zip tool to cut out the drywall and I also like 5/8" drywall. The dam cutter cuts through the side if the blue plastic box like it's not there... And unless your VERY carefull makes a mess....

William...."

Ever try a pilot tip roto zip blade? This is also a great place to insert my brother-in-laws favorite saying, "That's why mud comes in five gallon buckets!"

Of course I use the pilot tipped bits, that little pilot area on the tip turning at 20k (and hot to boot from the bit cutting the dry wall) takes about a micro second to melt its way into the box

Trace the box onto the wall with a pencil and THEN cut the hole.

Gez that sounds like a great idea, only problem is I don't mark the holes before I cut them as that would require an exact measurement of them, and remove the advantage of the tool, ie. hanging the sheet over the boxes and cans and then cutting them in the sheet for a perfect fit.

William.....

 

[VHF]

This thread had a good discussion of metal boxes, blue plastic boxes, and even the brown (fiberglass?) boxes, but no one mentioned the gray PVC boxes that come with slip-joint fittings ready to glue to PVC conduit.

I'm considering doing my whole garage with the gray boxes & PVC conduit. Advantages are no air infiltration through the boxes themselves, and with everything in conduit I can make future changes and additions. In addition to boxes with outlets for immediate use, I would probably locate several empty boxes around the garage--fed by PVC conduit run back to the panel--reserved for future applications.

That way, when I get a bigger compressor, lift, welder, or whatever down the road I can just pull the appropriate wires to the desired location at that time w/o having to tear open walls or resort to surface run conduit.

Any thoughts on the gray plastic boxes or the idea of putting in some extra empty boxes in the walls for future applications?

 

[rinny_tin_tin]

This thread had a good discussion of metal boxes, blue plastic boxes, and even the brown (fiberglass?) boxes, but no one mentioned the gray PVC boxes that come with slip-joint fittings ready to glue to PVC conduit.

I'm considering doing my whole garage with the gray boxes & PVC conduit. Advantages are no air infiltration through the boxes themselves, and with everything in conduit I can make future changes and additions. In addition to boxes with outlets for immediate use, I would probably locate several empty boxes around the garage--fed by PVC conduit run back to the panel--reserved for future applications.

That way, when I get a bigger compressor, lift, welder, or whatever down the road I can just pull the appropriate wires to the desired location at that time w/o having to tear open walls or resort to surface run conduit.

Any thoughts on the gray plastic boxes or the idea of putting in some extra empty boxes in the walls for future applications?

I have used those gray (carlin) boxes only in cases where I use the pvc conduit - and they are great. Mostly in wet spaces, etc. The only problem I had with them is getting appropriate screws and making them fit tight in the provided holes to hold on a cover. In many cases, I wind up stripping the holes, or the screws are too small and turn out

 

[Charles (in GA)]

That way, when I get a bigger compressor, lift, welder, or whatever down the road I can just pull the appropriate wires to the desired location at that time w/o having to tear open walls or resort to surface run conduit.

Any thoughts on the gray plastic boxes or the idea of putting in some extra empty boxes in the walls for future applications?

Those are weather proof, exposed use boxes that really are not designed to be mounted to studs (most I've seen have ears on the back of them for mounting), and poke thru sheetrock. They are very slightly tapered and won't lay flat on a stud and have the face parallel to the sheetrock.

Charles

 

[LoneGunman]

FS boxes are great for outside use, we use a lot of them on docks. I see no advantage in running PVC instead of EMT in the walls besides PVC being easier to work with.

Extra boxes with blank covers are always a good idea.

 

[tfi racing]

PVC in contact with thermal insulation is a no-no on this side of the border,not sure why,likely something to do with the FT-4 fire rating that pvc doesn't have,or maybe because the PVC boxes aren't really designed to be covered by wall sheeting.If its in the Canadian code book,the same rule may in the NEC as well.

 

[hidollartoys]

How about this, "I will use what I like and what I am comfortable with...... If you don't like it, TUFF!!"



"AMEN"

 

[Aceman]

PVC is hokey indoors IMO(except for wet locations). Diyer's do seem to like it though.......

But, if someone was holding a gun to my head and I had to run pvc, I'd go with 4 sq bracket boxes and mud(plaster rings). Trying to use pvc boxes (meant for surface mounting) installed flush with sheetrock is a disaster and just the wrong way to go about it. Emt and 4 sq brkt's are standard procedure when specs call for raceway installed wiring, rather than the typical cable method(romex,mc). Pvc must be secured much more often than emt too with 3/4 pvc needing supports every 3' and strapped within 3' of every box, etc.

 

[VHF]

I'd pretty much figured the gray PVC boxes were intended for wet locations & surface mounting, but thought maybe I could come up with a way to make them work in-wall (i.e. install blocking in the stud cavity onto which to mount boxes.)

Maybe it's time I got a tubing bender and learned how to work with EMT!

 

[octavio3311]

Hey guys - newbie here. I've been lurking for a couple of weeks gathering info for my garge make over this spring - I've found this forum very helpful. Thanks to all for all the great ideas.

Anyway - I've never posted before - but being an electrician, i felt inclined to do so.

The grey PVC boxes are intended for surface mouting - not recessed mounting. They are moisture & vapor resistant and are actually required for barn applications - real barns with horses and etc. They are to be used with romex or THHN (individual strands).

Blue boxes are the residential standard. They come in various depths and sizes - single all the way up to 6 gang I believe. They can be mounted on the studs (new construction) or you can use the old construction type that clamps the wall with wings. Blue boxes are to be used with Romex wire.

Metal boxes are for commercial applications - BX for most commercial buildings and MC for hospitals and medical facilities. Sometimes schools also require MC. MC is just like BX, however it contains a 3rd wire inside - a ground wire. When using metal boxes with BX wire and BX connectors - you will have to ground the device to the green ground screw in the box.

Sorry for the long post.

 

[octavio3311]

I'd pretty much figured the gray PVC boxes were intended for wet locations & surface mounting, but thought maybe I could come up with a way to make them work in-wall (i.e. install blocking in the stud cavity onto which to mount boxes.)

Maybe it's time I got a tubing bender and learned how to work with EMT!

PVC tubing is very easy to work with - you can heat it up with a heat blanket or a torch (low flame) and pretty much get any bend necessary. The also make 90 degree elbows and 45 degree couplers - depending on what you need, chances are you might not need to bend anything

 

[octavio3311]

Hey guys - newbie here. I've been lurking for a couple of weeks gathering info for my garge make over this spring - I've found this forum very helpful. Thanks to all for all the great ideas.

Anyway - I've never posted before - but being an electrician, i felt inclined to do so.

The grey PVC boxes are intended for surface mouting - not recessed mounting. They are moisture & vapor resistant and are actually required for barn applications - real barns with horses and etc. They are to be used with romex or THHN (individual strands).

Blue boxes are the residential standard. They come in various depths and sizes - single all the way up to 6 gang I believe. They can be mounted on the studs (new construction) or you can use the old construction type that clamps the wall with wings. Blue boxes are to be used with Romex wire.

Metal boxes are for commercial applications - BX for most commercial buildings and MC for hospitals and medical facilities. Sometimes schools also require MC. MC is just like BX, however it contains a 3rd wire inside - a ground wire. When using metal boxes with BX wire and BX connectors - you will have to ground the device to the green ground screw in the box.

Sorry for the long post.

 

[rinny_tin_tin]

Hey guys - newbie here. I've been lurking for a couple of weeks gathering info for my garge make over this spring - I've found this forum very helpful. Thanks to all for all the great ideas.

Anyway - I've never posted before - but being an electrician, i felt inclined to do so.

The grey PVC boxes are intended for surface mouting - not recessed mounting. They are moisture & vapor resistant and are actually required for barn applications - real barns with horses and etc. They are to be used with romex or THHN (individual strands).

Blue boxes are the residential standard. They come in various depths and sizes - single all the way up to 6 gang I believe. They can be mounted on the studs (new construction) or you can use the old construction type that clamps the wall with wings. Blue boxes are to be used with Romex wire.

Metal boxes are for commercial applications - BX for most commercial buildings and MC for hospitals and medical facilities. Sometimes schools also require MC. MC is just like BX, however it contains a 3rd wire inside - a ground wire. When using metal boxes with BX wire and BX connectors - you will have to ground the device to the green ground screw in the box.

Sorry for the long post.

Good and concise summary Oct! Thanks