In article ,
"Mike Marlow" wrote:
I cannot take any exception to the above post - it is technically correct.
I'll only add that I don't carry rolls and rolls of wire, so I'll simply
pull 12ga for everything. For me - it's easier and more cost effective.
For a commercial electricain who lives and dies by this work - maybe not so
much. The other benefit - many if not most of my work is subject to
"improvements" down the road - and not by me. Anticipating that home
owners, or church members or any other likely candidate will almost
assuredly have their fingers in this at some point, I do a couple of things.
I lightly load circuits, and I wire with all 12ga. Yeah - I know it does
not cover every conceivable in-house add-on, but I've at least done my best
to accommodate that eventual "oh - I'll just tie into this circuit" by the
well-intendeds of the world. Sure - it is overkill. Sorry about that. I
wasted $1.39.

For a 9'3" run. It's about a 15 cent per foot differential if buying 500
foot rolls and running 3 wires.

Depending what you have on hand and what you have to buy, the economics
work out various ways. If the outlets are already wired, you ONLY need
to wire the lights, and you're looking at buying black/white/green (or
bare) in 500 foot rolls it's $120 to get three rolls of #14 and $195 to
get three rolls of #12.

If you need the #12 anyway for outlets, and 500 feet is more than
enough, the #12 can actually be less money overall if it means not
buying any #14 - more or less your position.

If you are buying it by the foot (the economics of that are rarely good,
but should be checked at local suppliers especially if the total footage
is short) the #14 will definitely be cheaper.

On the third hand, 250 feet of 14-2 NM will only set you back $48.20
(all are HD's local prices, yours may be better or worse or better not
at HD.)

And, if you can find someone else's leftovers on craigslist (et al), it
might be a LOT cheaper if your job is not larger than their leftover
wire. If not wiring until March, that's a good opportunity to hunt for
someone that bought 3-4 rolls of THHN and ran out of project before they
ran out of wire - might try the wanted section to troll for that,
assuming you can filter the resultant spam. Otherwise just keep an eye
on it looking for THHN.

--
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