According to the electrical code. I must use a box when I connect
wires. Well, why do I need a small metal or plastic box just to place
a few wirenuts where two wires connect? A house IS A BOX. Any
building IS A BOX. The house or other building is a box in itself.
Therefore, any connection I make on wires contained inside of any
building, IS IN A BOX, and complies with the requirement to put wiring
connections inside of a box.
All right, I'll feed the troll a little (just in case some newbies on
here take him seriously)-
Or to put it another way- a box made out of something other than
kindling material. I found a connection like OP is proposing inside my
bathroom wall when I was cleaning up the wiring, and raising the mirror
cabinet to a height where I could actually see myself in it. The feed to
the original between-the-studs cabinet had been extended with a butt
splice and electrical tape (just floating in the wall), to feed the
lights above the cabinet and the ungrounded GFCI below it. I clipped off
that feed and abandoned it, and fished a new (grounded) wire to the
expanded J-box in the attic.
What I put in probably ain't code, strictly speaking (since I borrowed
unswitched power from an outlet in the bedroom next door to power the
gfci) , but it is a hell of a lot safer than what I ripped out. And the
wire nuts in the attic box are actually screwed on, and there is a lid
on the box now. (The electrician I hired to do an inspection obviously
never went in the attic- the connections were fanned out in the air
above the single-layer octagon box, with the wirenuts just loosely
engaged. I touched the rats nest, and several of the nuts went sproing,
off into the insulation somewhere. No romex clamps on anything, the wire
was just stuffed through the knockouts.)
On Wed, 17 Mar 2010 19:34:22 -0700 (PDT), Jack Hammer
If the box is a metal one, I can see where it may contain a fire, but
plastic boxes will add to any fire. Plastic burns. From having
burned plastic bottles and other plastics in my outdoor burn barrel, I
know how fast and hot plastic burns. I'd guess that plastic burns
hotter than wood. So, requiring a PLASTIC box is just useless
nonsense when it comes to containing a fire. It's just an outdated
code rule which no longer serves any purpose, ever since they allowed
On the other hand, a metal box might contain a fire for a short time.
Of course with modern cable being made with a plastic jacket, the fire
will quickly spread outward as the cable jacket burns. I recall when
both the boxes were metal and the cable was covered with a spiral
metal housing (BX), or the wires were in metal pipe/conduit. That's
when wiring was really safe. These plastic jacketed cables and
plastic boxes are a joke. If sparks fly the plastic will ignite and
burn faster than the wood around them.
I do agree that splices inside a wall are a bad idea because they can
not be located in the event that a connection becomes loose.
Therefore a box does offer a place to look for a bad connection. But
as far as preventing a fire, plastic boxes do nothing to stop a fire,
and actually add fuel to the fire. Personally, I have never purchased
or used a plastic box in my home, and I never will, I use metal boxes
for everything. About the only safe use for plastic boses is for
installing networking cables, phone wiring, or other low voltage low
current wires. In these cases they are not required by code, but they
do help keep the insulation away from wires, makes wiring easier, and
keep cold air from entering the home. This should be the ONLY thing
they are allowed for.
Nope. Consider possibly the oldest of "plastic": "Bakelite." Bakelite is
"thermo-setting" meaning the hotter it gets, the more the molecules hook
together. As some heat point, a Bakelite ashtray becomes one giant molecule!
As such, Bakelite cannot burn. If heated enough, it will char and decompose,
but it will not burn. That's exactly WHY it is used as electrical boxes,
distributor rotors, and electrical plugs.
At the other end of the spectrum are polystyrene packing peanuts. They won't
burn either - at least they won't support comubsion. They will melt and some
of the impurities will flame up but as soon as the igniting flame is removed
they wink out.
Jeeze! Wire insulation (most) won't burn either. UL certification won't
Sniff. Your loss. All commercial, plastic, junction boxes are UL rated and
must pass the ul94 5v test. This test specifies that an applied flame must
NOT generate a self-sustaining fire and no smoldering or burning material
may fall from the test item.
All that said, do you REALLY believe the nannies in federal, state, and
local governments would allow the sale of these things if there were ANY way
they could ban them for the sake of the children?
I will agree that the bakelite is good, and I have seen bakelite boxes
in some situations, especially older trailer houses. I feel pretty
safe with them, and they are durable and I will agree about the fire
But what about those flimsy blue cheap plastic boxes that everyone
uses these days. Not only do they easily break when they are nailed
on (the ones with nail brackets), but they are nothing but cheap soft
plastic which looks like they would ignite with the smallest amount of
flame. It looks like the same plastic they make kids toys from.
Besides the flame issue, the screw holes are not threaded. They are a
major hassle to get the screws into, and if an outlet is removed
several times the plastic strips and screws do not hold, or the
plastic breaks at the screws. In all the years I have done wiring, I
have never had to replace a metal box. If the screw holes stripped, I
just re-tapped them. If those cheap plastic things break or strip,
the whole wall will have to be torn apart, (all of that to save a few
I helped a neighbor wire his garage and he bought these cheap blue
boxes. I hated everything about them. They dont even have round
knockouts for cable clamps. The whole concept seems cheap and junky.
I hate everything about them.
As far as the jacket on romex being flame retardent, I disagree.
Where I live, we have to burn our garbage, unless we want to drive 12
miles to the town dumpster, which is locked half the time. So, I burn
anything that will burn. I have takes the stripped off jacket after
wiring something and tossed it into the fire. It burns hot and fast
leaving a dense black smoke. While a garbage fire is intense, so is
an overheated wire. I cant see that stuff NOT bursting into flame in
the event a wire gets a direct short and a breaker fails. At least
the old BX and conduit installations were encased in metal, which
would get hot, but would not flare up.
No loss. I like my metal boxes.
The government is NOT God. They are often wrong, and far too often
bribed by big businesses. Money talks....... Look at how long it
took Toyota to actually take action about their defective cars. I
wonder how much they paid the govt. to hush up.......
And what happens if in a few years the govt. find that the plastic
boxes are not safe. Will they force everyone to rip apart their walls
to replace them. The old metal boxes have been around since wiring
was first installed in homes. It's reliable. Even the old knob and
tube wiring was safer. Those porcelain insulators going thru every
piece of wood was very safe. The downfall back then was that
flammable cloth/wax insulation on the wires.
So you agree that SOME plastic will not burn. Well, that's a start.
I'm telling you that Underwriter's Laboratories says they WILL NOT BURN. If
you don't believe my reporting or the UL folks, go buy one of the damn
things (19¢) and go to work on it with a cigarett lighter. No luck? Try a
propane torch. Still no luck? Okay, break out the acetylene apparatus!
Report back on your scientific experiement.
Almost ANYTHING will burn if subjected to enough heat, even a human body. If
the house catches fire, I have no doubt that the insulation will disappear.
The operative rule, though, is will the object SUPPORT combustion. That is,
will it burn on its own without being constantly subjected to an external
There is nothing, NOTHING, involved in electrical distribution that will
support combustion. Not plastic boxes, not insulation on wires, not
electrical outlets, not wire nuts. Nothing. Period.
As I said earlier, if you doubt this absolute statement, try it yourself.
And throwing a hunk of insulation inside a 2000° kiln is not the test.
I agree metal boxes are reliable and have a long history of excellent use.
So are slate roofs. But there are other considerations: cost, weight, ease
of installation, and so on. The difference in price for one box is de
minimus - say $1.50 vs thirty cents. But if you're putting fifty boxes in
each new house and you're building a thousand homes a year, pretty soon
we're talking about real money.
And yes, if found unsafe, there may be agitation to rip out walls. It's been
done with aluminum wiring and asbestos.
Have you taken a plastic electrical box and put a lit match to it?
Anything can be incinerated but if you take a propane torch to a
plastic electrical box and set a spot on fire, it will go out as
soon as you remove the flame. It will not support combustion, the
same as plastic electrical insulation. However,it will be consumed
by flames if it's thrown into a fire that's fueled by something else.
Having seen the results of bad connections causing serious overheating and
fire inside of plastic boxes, I can assure you that they contain it well.
Although the plastic will eventually melt if the circuit is not broken, I
believe that in many respects they are safer than metal. They don't transfer
the heat through the plastic, and tend to have fewer openings in them to
allow sparks, and flame to escape, which also helps prevent the fire from
breathing. Secondarily, if you nick a conductor on a steel box, it will
ground. Not so on a plastic box.
thought that a splice has to be in a box and also should not be hidden
behind a wall.
I haven't used it, but I understand that there is an "approved" splice that
can be "hidden" as in not accessible.
I picked up two of them (one for 2 wire + ground, the other for 3 wires +
ground) but haven't used them.
I don't know what the NEC says about these but the UL folks don't seem to
have any problem.
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