Hello All! I am new here and looking forward to learning alot and contributing anything I can.

We have an unfinished basement we just finished Framing and I have roughed in all the outlets and wiring for them. I have installed the recessed lights but have not wired them yet.

So the way it is wired right now is confusing me. So When you come down the steps and hit the one 3 way switch, it turns on two lights in the main room and one in the laundry room. The other end of that 3 way switch is by the exit door. The Smoke detector is also going into that switch box but i can't imagine it being on the switch since it doesn't come on and off. The smoke detector than goes up to the other smoke det. Im guessing.

All the outlets will be on their own 20amp circuit.

Question 1: How would I run it if I want a switch in the laundry room for the two lights in there? On a separate circuit? or tap into the existing one?

Question 2: Should I rewire the smoke detector and how?

Sorry for the poor illustration and I am trying to do it from memory..... See Before and After.

 

I can't follow the diagram but my suggestion would be, to identify the each feed to each switch. You may have to disconnect all the switches, to do that. Mark each feed with a piece of black tape. Then connect one wire at a time, to see where it goes. Make a note of those too. There is no reason to have the smoke detectors on any of those switches.

 

The circuit for the smoke alarms needs to stay as is. Do not mess with it.

You cannot have any 14-2 on a 20 amp circuit.

 

Question 1: How would I run it if I want a switch in the laundry room for the two lights in there? On a separate circuit? or tap into the existing one?

Run a 14-2 cable from the panel into the laundry switch box.
Run another 14-2 cable from the laundry switch to the first 3-way.
At the laundry switch box, you can feed power to both the laundry switch and the first 3-way.

Question 2: Should I rewire the smoke detector and how?


Test the smoke detector and as Boss said, leave as is. Ensure you don't require a combination Smoke/CO detector.

Let us know if you need any advice on the actual connections.

There's an error on your drawing. 14-3 will be ran from stair 3-way to 2nd 3-way. 2nd 3-way will feed the can lights. You show cable going up to the lights from both 3-ways.

 

Why should the smoke detector be on a light switch?

 

Thanks for all the replies! That has helped a lot. To clarify, I am not using 14-2 wire on a 20-amp circuit. The 20a is for the outlets and I am running 12-2 there.

So run a 15amp circuit from the breaker box to the laundry room switch, then to the 1st 3 way and the two laundry room lights. Then a 14-3 to the other 3 way by the exit door. Then 14-2 up to the can lights.

What about the 3 ways in the stairs? How am I accounting for that power?

 

Whether you need a new circuit for listing is going to depend on the new and existing load on the circuit. How much is on the circuit now.

As for the smoke and the switch, it may have just been a convenient place to grab a power source, not that the switch controlled the smoke.

 

The cable that goes from the smoke detector to the old switch box can be eliminated. You will have a new power source. I can see you planned that in your drawing.

Stair 3-ways will be the same as the can lights.
Run another 14-3 cable to 2nd stair switch, then 14-2 from 2nd switch up to light.

So in the 2 gang box by the stairs, you will have 3 cables:
14-2 source power
14-3 to can light switch
14-3 to stair switch

 

Ok.... I modified my plans.... Take a look. Circuit #2 will supply power to the all the smoke detectors and the laundry room lights and switch. Circuit #1 will be the can lights and the steps. Circuit #3(not pictured will be the outlets).

In wiring the smoke detector to not be on the switch be receive power, do I just wire nut power source to smoke det. line and a pigtail to the switch?

 

Yes, the smoke detector should be wirenutted to the constant source. Depending on your local building/fire code you may also need a hardwired carbon monoxide detector (or combo smoke+CO) and it may need to be interconnected to detectors on other floors. You may not just be able to put it back as is.

 

OK, I didn't realize the detector, and other things, were fed by a non-switched source from the old switch box.

So now the laundry switch box will have 3 cables. Source, light, detector.
Connect all whites together.
Connect black source to detector, with a pigtail to the switch.
Connect light black to other switch terminal.

 

Ok thanks all. That helps tremendously! Feeling pretty confident now.