Electrical outlet question

I need to add a gfi outlet to my wifes bathroom. I want to add it to the cu rrent light switch box. This box currently has two switches, one for the fa
n,light and one for the vanity light. Each switch has a white wire, a black wire, and a ground. When checking with a voltmeter, the white wire on both switches always has power. Each black wire only has power when the switch is turned on. I am assuming the white wire is the power wire. Can I take th ese white wires off the switches, connect them to the top and bottom "hot" terminal on the gfi outlet, then feed the switches from both terminals on t he other side of the gfi? When I did this messing around with the switches, everything worked properly. I just thought that the black wire was always the constant power wire.
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snipped-for-privacy@yahoo.com says...

current light switch box. This box currently has two switches, one for the fan,light and one for the vanity light. Each switch has a white wire, a black wire, and a ground. When checking with a voltmeter, the white wire on both switches always has power. Each black wire only has power when the switch is turned on. I am assuming the white wire is the power wire. Can I take these white wires off the switches, connect them to the top and bottom "hot" terminal on the gfi outlet, then feed the switches from both terminals on the other side of the gfi? When I did this messing around with the switches, everything worked properly. I just thought that the black wire was always the constant power wire.
If your switches are wired like the following, then you DO NOT have hot/neutral power at the switches and will need to run a new wire...
http://www.make-my-own-house.com/images/elcodedblack.jpg
If your switches are wired like this, then you have power and can add an outlet...
http://www.buildmyowncabin.com/electrical/wiring-light-switch.gif
If you do not understand the difference, hire an electrician.
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Ok, in the first example, are you saying it is possible to power a gfci and for it to work, just that the GFCI portion will not work on the outlet as intended?
I appreciate it!
On Monday, March 25, 2013 8:15:13 AM UTC-5, snipped-for-privacy@yahoo.com wrote:

current light switch box. This box currently has two switches, one for the fan,light and one for the vanity light. Each switch has a white wire, a bla ck wire, and a ground. When checking with a voltmeter, the white wire on bo th switches always has power. Each black wire only has power when the switc h is turned on. I am assuming the white wire is the power wire. Can I take these white wires off the switches, connect them to the top and bottom "hot " terminal on the gfi outlet, then feed the switches from both terminals on the other side of the gfi? When I did this messing around with the switche s, everything worked properly. I just thought that the black wire was alway s the constant power wire.
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I need to add a gfi outlet to my wifes bathroom. I want to add it to the current light switch box. This box currently has two switches, one for the fan,light and one for the vanity light. Each switch has a white wire, a black wire, and a ground. When checking with a voltmeter, the white wire on both switches always has power. Each black wire only has power when the switch is turned on. I am assuming the white wire is the power wire. Can I take these white wires off the switches, connect them to the top and bottom "hot" terminal on the gfi outlet, then feed the switches from both terminals on the other side of the gfi? When I did this messing around with the switches, everything worked properly. I just thought that the black wire was always the constant power wire.
First off the disclaimer: The newer code requirement is for GFI outlets in bathrooms to be 20-amp and also separate from the lighting circuit. So if you wish to do it the correct way, you have to run a 20-amp line from the panel.
If you wish to do it the way you're intending, then some simple re-splicing is in order. First turn off the power, then take the white wire going to the fan switch and pigtail 3 black wires to it. Leave the existing black wires on each switch alone. Take the white wire off the switch for the vanity light. Connect one of the black pigtail wires to each switch, (leaving one for the moment.) Either up in the attic or behind the vanity light you're going to find the main splice for the bathroom wiring. In this splice you will have to take the white wire that ran to the vanity light switch off of the hot wire splice and splice it to the neutral wires. This leaves you with one black pigtail wire and one white neutral wire back at the switches. Once power is restored, these 2 wires will supply power to the GFI. I'm sure you can figure out that all of the grounds go together and to each device.
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On 3/25/2013 9:29 AM, Rich. wrote:

Not likely there is a "main splice for the bathroom wiring".
The wiring method that makes sense is a 2-wire romex from the vanity light and a 2-wire from the fan.
The NEC requires all wires for a run be in the same cable or raceway. You can't get the hot from the fan and the neutral from the light.
There is a duplicate question from a long thread in alt.home.repair which addresses the issues. The OP probably doesn't like the answers he is getting there.

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snipped-for-privacy@yahoo.com wrote in

This was answered, quite thoroughly, by myself and several others, in alt.home.repair when you posted it there.
You CANNOT do this safely or legally because you DO NOT have a neutral in that box.
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