I have a very small house and have begun wiring rooms with 12/2 with 20
amp breakers. I realize this is overkill especially for overhead
lighting (of which I have only 2 lights). But the increased cost
doesn't bother me and it makes my circuits and wiring job much simpler.
Also most of the lights and switches are rated for 15 amps with the
exception of outlets which actually need to support appliances
requiring a 20 amp circuit. The overhead lighting shares the circuits
with other lights and outlets.
Are there any problems wiring this way with regard to safety or code
Nope. There's nothing wrong with with going with 20A and 12/2 instead of
15A and 14/2. I just built a new garage, and did it all with 20A and 12/2.
I was like you, yes, it cost more, but I wanted the heavy-duty stuff.
Besides, the only extra cost is really in the wire.
20 amp on light ONLY circuits are probably a bad idea.
most light fixtures have very small wires, 14 or even 16 gauge.
lets say a partial short occurs.........
a 15 amp breaker will likely trip a 20 amp will continue to happily
supply the short:(
I had a overhead light above my bed do this one time in middle of
night, walking out of bedroom for bathroom i turned on light and heard
arcing saw sparks reflected off wall......
i had lost pillow and need light to find it.........
turned off switch fast and didnt get back to sleep. talk about instant
arc fault breakers didnt exist at the time about 10 years ago. i
replaced every fixture in the house...
pure lighting circuits have no need for 20 amps!!!
volts times amps is roughly watts. on what home application would you
need over 6120 watts of lighting on a single circuit?
no 20 amp light only circuits I am not lighting a ballfield......
I don't know if code supports this...but I personally agree with you.
In my new house, all outlets and dedicated circuits (fridge,
microwave/vent) are 20 amps on 12/2 (yellow PVC jacket), and all
lighting circuits are 15 amps 14/2 (white PVC jacket).
Speaking of over kill, I'm probably adding nearly twice as many
circuits as required...lots of outlets.
Well the 12/2 wiring is already in and would be a PITA to remove.
Nothing wrong with a 15 amp circuit with 12/2 wiring for
lights....right? Also, I could easily extend the circuit to additional
The 20 amp circuit in the dining room stays. We run an air
conditioning unit in there. The lights used to dim when we turned it
on. Not any more.
In practical terms, fitting a mess of 14/2 wires into a box is a whole
lot easier and safer than the same number of 12/2 wires. Infact, code
says how many more 14/2 you are allowed.
There is nothing "easier" about going all 12/2, unless you can't tell
the difference between a "2" and a "4". Hell, here the 14 is even
yellow coated instead of white, so you don't even have that. Buy one or
two rolls of each, and replenish as needed.
And unless you have some wierd applience plug, then everything you have
is 15A or less, as are all the switches, lamps, outlets, etc.
many switches and outlets have easy wire connectors for 14 gauge wire,
12 gauge probably wouldnt fit, of course you can always wrap the wire
around the screws but sometimes its helpful to use the back install
connectors where the screw holds the wire
the backstap connections are poor quality i dont recommend them
try a little piece of romex in your planned outlets and switches.
of course you can pay big bucks for 20 amp rated outlets
keep the light circuits seperate from the outlets and dont foget GFCIs
Outlets that have easy wire connectors will work for both 12ga
and 14ga - US market would demand it. These tend to be spec-grade
(like Hubble), and they're not going to skimp on something like that.
US "T" style 120V outlets with both 15A and 20A interchangeability
aren't very expensive.
They may be in Canada, where 120V/20A general purpose circuits are
just being permitted, but that won't be for long.
Chris Lewis, Una confibula non set est
It\'s not just anyone who gets a Starship Cruiser class named after them.
Frankly I use 12/2 exclusively. I'd use 10/2 but it is too hard to work
with. I sleep better knowing overkill is awake. When everything is new
14 may be sufficient, but as time takes its toll, 12 will stay safer
Just my 2 centavos worth, but ...
If you need 12/2 it's not overkill. If you don't, it is,
b/c 12/2 is harder to work with, costs more, and
could cause more trouble if you have a short.
The real issue for po' me would be circuit design.
If one designs a circuit with reasonable expectation
that it'll draw max amps of 15 in any normal usage, then
14/2 is indicated. If max 20 a. then 12/2.
And if circuit design hasn't been fully considered,
it's time to bone up on it.
I realize that there may be a circuit or 2 in some
situations where it's difficult to predict usage,
amp draws, etc. Fudge factor could be called for.
To wire *everything* well above expected usage
(i.e. nickel/dime light circuits) is quite another thing.
Pease pudding hot,
Pease pudding cold,
Pease pudding in the pot
Nine days old.
keep existing lightning only circuit just that but protect 12 gauge
romex with 15 amp breaker.
i have a couple circuits like that around here one is 10 gauge 20 amp
feeding shed, its a long run i didnt want line losses if someone ever
used a circular saw back there....
i use shed for styorage only but someone else is all set
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