K&T to Romex

[jtfoxman]

Hey all.
I have K&T running in my attic that I assume is coming from one of my outlets in a bedroom since the attic is on a bedroom circuit and they just didn't replace the k&t. Now there is an old style knob switch that controls the attic light, a closet light and an outlet in the bedroom. This switch must be on for any of these to get power. I want to change that by replacing all the k&t in the attic with romex but keeping all the k&t that runs into the attic and just changing over to romex once the k&t hits the attic. The one problem I am having is the switch has 2 k&t wires and I do not know what they are. I was wondering if I could remove the switch and splice these wires together in a box and eliminate the need to keep the switch on to operate the lights since the power will all be on. I hope this was explained well enough. Can anyone help me out?

[HayZee518]

any switch that is installed either on romex or knob and tube is switching the hot wire. the neutral is never switched except when its used as a traveler in a three way switch circuit and should be marked with a wrap of black tape on both ends. yeah go ahead and splice them together.

[jtfoxman]

Thanks alot.

[jtfoxman]

Ran into another issue. Just found out the rest of the circuit is ungrounded. All the outlets have ground wires connected but I'm guessing the K&T runs to it first so there is no ground. There is an outlet that is on another circuit on the other side of the wall where the power feeds the first outlet on the circuit. My question would be can I ground this circuit to the other outlets ground wire. The other circuit is grounded and has only 3 outlets on it. The circuit without the ground has 3 outlets and 3 lights.
Thanks!

[HayZee518]

ungrounded circuits which consist of outlets are replaced with gfci receptacles. they don't sell two wire outlets anymore. with k&t the lights don't worry bout a ground.

[jtfoxman]

So I can't just run a new ground at the start of the circuit? Every other outlet the grounds are all connected back to the first one.

[HayZee518]

ok, if you wanna run a ground wire to each receptacle ok but each box has to be grounded also. if I remember correctly in the old days they used three inch octagon boxes and cast iron ceiling cases with a clamp that locks the loom into the case. these also need to be grounded. any metal enclosure has to be grounded for safety. minimum size is #12 solid or stranded with stakons.
each box in your run has to be bonded to the entire grounding system.
some of these old cast iron boxes are fastened to the old "gas" lighting piping. they terminate at a fitting called a hickey.

[jtfoxman]

So every receptacle and switch box in my house needs to be grounded?

What could happen if the receptacle ground wires are just connected to the receptacle ground screw, or the switch ground wires just to the switch or together if there is no ground screw? Same with a light fixture without a ground screw? Is this dangerous?

My home when i first moved in all the receptacle wires were grounded to only the box and the tester showed that none were grounded. So I wired the grounds to the receptacles and all was ok. I just don't understand the need to round everythng to the box also when all the grounds run back to the main breaker and the receptacle is screwed right to the box.

[HayZee518]

some outlets had a spring attached for intimate contact with the yoke and fastening screw [6-32] so when the device was screwed into the box it automatically grounded it, but the code part was re-written to ground all boxes plus grounding the device yoke regardless of the grounding feature. it was all a matter of safety. an ungrounded box "could" become an energized hazard for personnel. touch a box and a earth ground say a faucet and you could get electrocuted. a fault current, [ leakage path" ]to ground may be a high resistance, not enough to blow or trip a breaker would in fact energize the box to 120 volts - more than enough to kill someone.

[jtfoxman]

So what you are basically saying is that i should go to every light switch and receptacle in my house and pigtail the ground wires to the junction box along with the switch/receptacle with an appropriate ground screw. What happens if the box does not have a grounding screw hole? I don't believe any box in my house is grounded like this. All are just grounded to the receptacle\switch. Thanks for the clarification HayZee.

[HayZee518]

box screws, like the ones that fasten a wire to the box has a clamp with a 1" long screw that holds the clamp and wire - it can be either 10-24 or 10-32 thread. even the old , and I mean old boxes of stamped galvanized metal from the 1920's have tapped 10-24 holes in the box. the cast iron boxes don't have grounding screws mainly because they didn't need them. circa 1920 knob n tube wiring, they didn't know anything about grounding. services used a solid #8 copper wire in a metallic sheathed jacket from the panel to the water pipe. most services were 30 amp or 60 amp.

[jtfoxman]

I hate to bother you with more questions but I like to know as much as possible when I'm doing something. And you seem to be the resident expert on electrical work. Why wouldn't the box become hot if there was a problem with the ground with it grounded right to the box? If the receptacle can become hot if there is a problem why not the box?

Thanks for all the direction. All my boxes have the clamp with the screw in the back holding the wire coming into the box so all I'll have to do is pigtail a piece of wire from the existing ground wires and connect to this screw. Should take me a few hours to do my whole house if all goes smooth. I don't believe i need to do this as soon as possible but some time soon should suffice. You agree?

[HayZee518]

well, this is why they say to scrape off all paint off enclosures when installing a grounding lug or bar [i.e. sub-panel] make sure the metal in a box is shiny and bright, use a sta-kon to make up the ground, [the crimp has to be tight] if you use a grinder with a three wire cord and if something happens within the field coil that causes the insulation to break down and 120 volts is applied to the "grounded" green wire. you'll have 120 volts on the supposedly grounded wire when in actuality it isn't grounded because of a loose wire on the outlet [green screw ground] or box grounding screw. [pigtail from outlet to box] grounding system from any box to the panel ground should be at zero potential anywhere in the system.

[jtfoxman]

Thanks for the knowledge. I think I'm all set.

[jtfoxman]

ok, if you wanna run a ground wire to each receptacle ok but each box has to be grounded also. if I remember correctly in the old days they used three inch octagon boxes and cast iron ceiling cases with a clamp that locks the loom into the case. these also need to be grounded. any metal enclosure has to be grounded for safety. minimum size is #12 solid or stranded with stakons.
each box in your run has to be bonded to the entire grounding system.
some of these old cast iron boxes are fastened to the old "gas" lighting piping. they terminate at a fitting called a hickey.

So your saying I can run a wire from the first outlet on the ungrounded circuit and connect it to the last outlet on the grounded circuit. The first outlet on the ungrounded circuit feeds the rest of the outlets and all ground wires are attached to each outlet exept for that first one. That's why i just want to run the ground wire to a grounded outlet on another circuit since they are practically back to back.
Is this allowable by code to jump a ground to another circuit? And I will make sure all outlets are also grounded to the box as per code.