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  1. #1
    Join Date
    Dec 2009
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    15

    Default House not wired with ground

    I bought a house built in 1950's and am doing some updating throughout. The wiring in the house does not include any ground. If I am replacing 2 prong outlets and going to 3 prong, can I use a ground wire from the ground screw and ground to the metal box? If not any suggestions other than starting from scrath and re-wiring house from panel??

  2. #2
    Join Date
    Oct 2010
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    17

    Default Re: House not wired with ground

    Quote Originally Posted by cregan529 View Post
    I bought a house built in 1950's and am doing some updating throughout. The wiring in the house does not include any ground. If I am replacing 2 prong outlets and going to 3 prong, can I use a ground wire from the ground screw and ground to the metal box? If not any suggestions other than starting from scrath and re-wiring house from panel??
    Does the main panel have a ground? Either to a grounding rod out side or to a water pipe that goes threw the ground to the street.

  3. #3
    Join Date
    Sep 2009
    Location
    Albany, GA
    Posts
    19

    Default Re: House not wired with ground

    Quote Originally Posted by cregan529 View Post
    I bought a house built in 1950's and am doing some updating throughout. The wiring in the house does not include any ground. If I am replacing 2 prong outlets and going to 3 prong, can I use a ground wire from the ground screw and ground to the metal box? If not any suggestions other than starting from scrath and re-wiring house from panel??
    Based on your description ("The wiring in the house does not include any ground."), running a jumper between the grounding screw on a 3-prong receptacle and the grounding screw on a metal box will have no effect and could actually create a serious safety hazard. While you may be able to plug a three-plug cord into the receptacle, there will be no grounding protection, which could lead to electrical shocks or fires. The grounding terminal on a receptacle is designed to divert electricity away from you and your house wiring in the event of a short-circuit in a plugged-in device, as well as triggering the circuit breaker to shut off. Without this protection, you risk the possibility of severe injury from shock/electrocution as well as fire caused by overheated wiring.

    The same is true if you use a grounding adapter. Unless the metal box is connected to a ground wire, the adapter would provide no grounding protection.

    *ONLY* if your metal boxes are grounded back to the service panel with a third wire, then you can safely use a jumper wire between the receptacle and the grounding terminal on the metal box, assuming that the service panel is properly grounded to the earth. Considering your description of the wiring as well as the age of the house, I highly doubt that is the case.

    Your best solution is to consult an electrician about upgrading your wiring. Another option is to use GFCI receptacles instead of standard three-prong receptacles. A ground-fault circuit interrupter (GFCI) would provide you with a 3-prong receptacle as well as electrocution protection (a GFCI functions by detecting imbalances in amperage between the hot and neutral wires and is designed to quickly shut off the circuit to prevent electrocution; they are required by code in wet-locations like outdoor receptacles, kitchens, bathrooms, garages, etc.). You can purchase 15-amp GFCI receptacles for about $15 apiece. If you do you use this solution, you are required by code to label the receptacle as "ungrounded."

    Note that GFCIs are sensitive devices that must be wired in a precise manner in order to function properly. If you use them, be sure to follow the including installation instructions exactly. Also, GFCIs need to be tested once a month, as they do eventually wear out and stop providing electrocution protection (when this happens, they still provide electricity, which can be a dangerous situation). Another factor is that, because they are designed to be personal safety devices, they are extremely sensitive and sometimes "nuisance-trip," particularly when supplying high-current appliances. While this might not be a big deal for an outlet controlling a lamp, imagine going on vacation for two weeks and coming home to find that your refrigerator has been without electricity for all that time because of a nuisance trip.

    While the GFCI solution may provide a work-around, it won't cover everything. It's still possible to receive a shock from a device plugged into a GFCI (especially an ungrounded one), although the devices generally trip quickly enough to prevent serious injury. Persons who are especially sensitive to electric shock (such as folks with pace-makers or heart conditions) may still be at risk for severe injury. Additionally, the GFCI will still not provide true grounding protection. All of today's fancy modern electronics are very sensitive to inevitable variations in line voltage, so surge protectors work by diverting excess voltage into the ground wire. Even if you plug the surge protector into a GFCI that is not grounded, voltage spikes would have no escape path out of the protector and would be passed into your electronic device, potentially causing severe damage.

    My strongest and best suggestion is to have a licensed electrician upgrade the wiring to modern standards.
    -Cameron Lashley

  4. #4
    Join Date
    Dec 2009
    Posts
    15

    Default Re: House not wired with ground

    The main panel does not have a ground. In re-wiring the house, what kind of cash am I looking at for a 4 bedroom cape??

  5. #5
    Join Date
    Dec 2010
    Posts
    5

    Default Re: House not wired with ground

    Quote Originally Posted by cregan529 View Post
    The main panel does not have a ground. In re-wiring the house, what kind of cash am I looking at for a 4 bedroom cape??
    Get 3or4 quote's from professional licensed electricians. It will be well worth it to have the peace of mind that you have a safe home for your family.

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