If running new electrical romex, run 14/3 or 12/3 for today's smart devices

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Just wanted to toss this out there if anyone is currently or future remodeling: best to run 3 wire electrical wiring for today's smart switches (ex: light or fan switch) such as 14/3 or 12/3.
My house was built in 2007 so I may be ok (NEC code did not require running neutrals til 2011'ish?). I have to investigate this coming weekend to see if I have all white wires in a wire nut behind my existing manual switches and do some testing to ensure they are indeed the required neutral white wire for smart switches.

I'm no stranger to doing my own DIY electrical wiring work. My 2 car garage came with a single light bulb and a single 15amp outlet. After lots of research and having the city inspector come pass my inspection, I have a subpanel, 12 110v, 5 220v receptacles and T5 lights everywhere (it's my wood working shop).

But this neutral wire required is...confusing. I'll be talking to some electrical industry buddies about it for clarification. What confuses me is many talk of using 14/3 instead of the standard 14/2 to give you that extra red wire. But then, many talk of re-using the 14/2 white wire and putting black tape upon it to re-identify it as a load wire.

I guess (i'm no electrical expert, I just play one on TV) if you are curious about smart switches in your house in the future and are remodeling now, talk to a licensed electrician about neutral wire requirements for a smart home.
 
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should have a running post here about what kind of devices people have installed into their households for automation. I know light switches and electrical outlets and thermostats. I just now came across a whole house humidifier that requires it's own 18/7 wire (thermostat wire) since the device and controller attaches to your furnace unit. Great...another wire to run! Luckily, have not yet patched up my drywall so is still possible.
Later down the road, will be looking at smoke detectors and such as well.
 

mat200

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FYI - I really enjoyed the following video on the subject of Smart Homes from

TYM Smart Homes & Home Theaters
Published on Dec 18, 2017

How To Wire A Smart Home - Top 8 Things for Smart Home Wiring

 

eeeeesh

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Wait

When you talk about 14-3 or 12-3, the Romex cable actually has 4 wires. The 14 or 13 is the wire size. #12 is a heavier gauge, can handle up to 20 amps and usually has a yellow sheath. #14 has a white sheath and is good for up to 15 amps
  • Black - Hot
  • White - Neutral
  • Bare Copper - Ground
  • Red - Usually an extra 'Hot'
Most circuits is a modern house are commonly wired with 14-2 Romex (Black, White, Bare) that's all you need for a smart switch

It is very common to use 14-3 or 12-3 when you have a Fan with a light and you want two different switches controlling it. OR you have a situation where you want two switches to control one light (called a 3-way) where the Red wire is designated as a 'traveler'

Smart switches require a neutral to work, because without it they can not use the 120v electricity to power them (just like a light wont work, unless it is connected to a not and a neutral).

Some people try to cheat by using the ground wire instead of the neutral, after all the neutral and ground are connected together in the main panel, but this is not safe to do.
 
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Wait
Most circuits is a modern house are commonly wired with 14-2 Romex (Black, White, Bare) that's all you need for a smart switch
As I'm learning this... yes, you only need 14-2 for a switch to give yourself the neutral requirement IF the power feed comes to the switch first. There are those older homes out there that the power feed comes to the source (light, fan, etc) first, not the switch so they remarked the white with black tape to identify it as hot, not neutral (well, I mean that was the allowable code before 2010'ish but they changed it because many electricians or DIY folk did not mark the white with black tape and that caused injuries). So that means, you would need an additional wire from the source to the switch to carry along the neutral. The old method was what was called switch loop or such which is no longer electrical code. And if this is done using the ground wire or using switch loop (since both are a no no in today's electrical code), your home insurance doesn't have to pay anything if house fire damage.
 
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FYI - I really enjoyed the following video on the subject of Smart Homes from

TYM Smart Homes & Home Theaters
Published on Dec 18, 2017

How To Wire A Smart Home - Top 8 Things for Smart Home Wiring

I've watched that vid months ago and it did help me. However, there are the tiny itty bitty things that the gentleman can not cover. Such as my new found whole house humidifier (really helps during winter time for heating...and for allergies through the year) which is attached to the furnace return or exit and requires a thermostat. For now, I'll be running a 18/7 wire from my future Home Automation box to this humidifier thermostat. Later, I'll investigate what it takes to convert to Z-Wave or something. Never tackled thermostats before so unsure if 18/7 is overkill or if a wire is needed at all. But since I have holes in my wall, best to hardwire it now.
Hence, my idea that here in Home Automation forum, for folks to list the items they have hardwired or done with wireless so that others can be aware of. I'm only going off a Amazon review of a person who installed this to his Nest thermostat which requires 18/7. Who knows...I could be totally wrong :)
PS: new retail is around $200. Gots a guy selling new in box for $50. Is why I am jumping on it. I love bargains!
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mat200

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... Never tackled thermostats before so unsure if 18/7 is overkill or if a wire is needed at all. But since I have holes in my wall, best to hardwire it now.
Hence, my idea that here in Home Automation forum, for folks to list the items they have hardwired or done with wireless so that others can be aware of. I'm only going off a Amazon review of a person who installed this to his Nest thermostat which requires 18/7. Who knows...I could be totally wrong :)
..
lol.. I would probably also run N+1 ( in this case 2 ) cat6 to it also.. thinking one day I'll upgrade it to a wired MS Goonestazonple ( after the big merger ) IoT voice activated humidifier...

man.. smart home stuff can quickly over whelm you.
 
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lol.. I would probably also run N+1 ( in this case 2 ) cat6 to it also.. thinking one day I'll upgrade it to a wired MS Goonestazonple ( after the big merger ) IoT voice activated humidifier...

man.. smart home stuff can quickly over whelm you.
ahh...yes! good idea! 2 more Cat6 cables wouldn't hurt! My furnace is located in a small room which contains my hot water tank and sprinkler system rainbird control box. Hmm... Maybe I should run 4 cat 6 :)
 

mat200

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ahh...yes! good idea! 2 more Cat6 cables wouldn't hurt! My furnace is located in a small room which contains my hot water tank and sprinkler system rainbird control box. Hmm... Maybe I should run 4 cat 6 :)
BTW @Holbs here's another youtube channel on home building that I enjoy watchings:
 
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will check that out mat.
Side note: I think this Home Automation thing is leading me down a dark path, the same as wood working did. Started off with a Bosch 4100 contractor saw and a router which eventually lead me down to taking over my entire 2 car garage for wood working equipment :)
My newest consideration for Home Automation pre-wiring considerations: z-wave controlled motorized cellular window shades! Guess I should slap in some 16/2 speaker wire to every window for future proofing. Rather spendy for motorized shades/blinds. DIY stuff would run over $100 per window. Full retail setup would run $300-$500 per window.
 
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