Adding a light to a switched circuit with power into light?

[SuburbanDad]

My garage currently has a light switch for a single lamp holder. I'd like to add a second lamp holder to the same circuit. The power from the panel runs to the lamp holder box, then on to a constantly powered outlet (garage door opener plugs in here) and to the light switch.

I am an electrical novice so I took a few photos from the attic space above the garage and tried to draw what I see, with the second lamp holder added. I omitted the grounds for simplicity, and pretended blue is white (neutral).

Looking for feedback regarding whether what I've drawn up is logical and won't cause any obvious issues. I understand codes are local so I'm just looking to see if this is the basic idea.

Essentially I'm asking if I can just add 14-2 Romex via pigtail at the existing light to the red switched hot and white neutral. Seems there's an unused slot on the box, so a simple job if I'm thinking about this correctly.

 

[The Cobbler]

simply add 14-2 to the wires that are feeding the existing lampholder

 

[SuburbanDad]

simply add 14-2 to the wires that are feeding the existing lampholder

Thanks! Took me longer than I'd like to admit to understand the current situation since the switch is not receiving power first. I'm a mechanical guy... or at least more mechanical than electrical.

 

[SuburbanDad]

Mike93lx replied in a duplicate thread I made accidentally. His message was:


"Either way, get rid of the back stabbed switch or at least move the wires to the screws.

As-is, it looks OK to me. Adding another fixture should be fine. Where are you located?"

Mike, I'll probably wire in a smart switch but good catch on the back stabbing. Every time I open something up in this house...

Located in VA.

Thanks for the help!

 

[mike93lx]

Mike93lx replied in a duplicate thread I made accidentally. His message was:


"Either way, get rid of the back stabbed switch or at least move the wires to the screws.

As-is, it looks OK to me. Adding another fixture should be fine. Where are you located?"

Mike, I'll probably wire in a smart switch but good catch on the back stabbing. Every time I open something up in this house...

Located in VA.

Thanks for the help!

Adding your location to your profile will help in the future.

If there is one back stabbed, there are more. I'd spend a day digging through switches and receptacles

 

[The Cobbler]

I meant to merge the 2 threads and delete the unnecessary posts, but I goofed .

 

[mike93lx]

I meant to merge the 2 threads and delete the unnecessary posts, but I goofed .

Pay cut for you!

 

[SuburbanDad]

Adding your location to your profile will help in the future.

If there is one back stabbed, there are more. I'd spend a day digging through switches and receptacles

Probably right. I've replaced many of them and don't remember others being done that way, but I get the sense that parts of this house were built on a Friday afternoon...

I can open up the rest of them and check to make sure.

I'll add location now. I've been a lurker but there are too many helpful folks here not to take advantage.

 

[beemerphile]

Thanks! Took me longer than I'd like to admit to understand the current situation since the switch is not receiving power first.

Looks like it does to me. Line goes to switch then to light. Neutral runs straight to light. If the line went to the light first, it would be a switched neutral - which would make the light go on and off but is not good practice for wiring a light switch.

 

[SuburbanDad]

Looks like it does to me. Line goes to switch then to light. Neutral runs straight to light. If the line went to the light first, it would be a switched neutral - which would make the light go on and off but is not good practice for wiring a light switch.

There's no wiring running directly from panel to light switch - it runs to the light, then to the switch and back.



I think it's like the bottom arrangement here, just with one light currently:



I think I see what you're saying though. The switch is still in the hot black wire rather than running through bulb and switching on the neutral side before returning to panel?

 

[beemerphile]

The wire goes first into the box that the existing lamp is in, but the circuit takes it through the switch before it gets to the lamp. They are using the lamp box as a junction box for the wiring.

 

[SuburbanDad]

The wire goes first into the box that the existing lamp is in, but the circuit takes it through the switch before it gets to the lamp. They are using the lamp box as a junction box for the wiring.

Think I've got it now! And that keeps the outlet hot at all times. I suppose I understood the path, but was not describing correctly. The junction box explanation makes sense.

 

[SuburbanDad]

Any idea why my switches all have a neutral wire even though house was built in early 90s? (Realized this when I started replacing with wifi switches.)

 

[mike93lx]

If power is fed to the switch box first, there has to be a neutral

 

[SuburbanDad]

If power is fed to the switch box first, there has to be a neutral

I'm probably not asking the right question again. Guess I'm asking why they did the below version of this:



With only one light on the circuit, couldn't you simply do the top version and run switched hot white wire directly to lamp holder? Thereby running 2 wire Romex instead of 3? Most areas of the house seem to have the cheapest possible installation.

 

[beemerphile]

It was uncommon in the 90’s to run the neutral to the switch because it cost money and performed no function as evidenced by its being coiled and nutted. Good to have these days though so you lucked out.

 

[SuburbanDad]

It was uncommon in the 90’s to run the neutral to the switch because it cost money and performed no function as evidenced by its being coiled and nutted. Good to have these days though so you lucked out.

They did that, but seemed to have beaten holes in the engineered I joists with a big rock rather than using the perforated knockouts.

 

[sparky 1971]

It was uncommon in the 90’s to run the neutral to the switch because it cost money and performed no function as evidenced by its being coiled and nutted. Good to have these days though so you lucked out.

It was fairly common in bedrooms especially. Power to the light box, 14/3 to the switch (hot, neutral, ground, and switch leg). Then 14/2 was pulled to the receptacles from the switch box, and also from the light box, maybe to the opposite wall, maybe to another bedroom. I've never done it that way, but have been in plenty of houses that did, going back into the 1950's. I'm guessing it was to save wire, which it probably did.

OP: don't worry about it. All you have to do is run a cable to the new location and hook up to the same wires powering the existing fixture.

 

[beemerphile]

It was fairly common in bedrooms especially. Power to the light box, 14/3 to the switch (hot, neutral, ground, and switch leg). Then 14/2 was pulled to the receptacles from the switch box, and also from the light box, maybe to the opposite wall, maybe to another bedroom. I've never done it that way, but have been in plenty of houses that did, going back into the 1950's. I'm guessing it was to save wire, which it probably did.

I've never seen that shortcut, but I don't have your level of experience going in behind someone else's work. Since the neutral was not used for downstream receptacles, this one was just wasted wire. I would not wire the circuit this way because I always separate lighting and receptacle circuits so you aren't left in the dark with a shorted plug in your hand that you just attempted to plug in. I also wire all receptacle circuits with 12 AWG and all lighting circuits with 14 AWG. Wiring power first to the switch box provides the neutral for electronic controls and eliminates the need to use a taped white on a 14/2 for a switch leg return to the light box.