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How To Add Ground Wire To Old House

How To Add Ground Wire To Old House

Thinking of upgrading? Wondering how to add ground wire to an old house? You came to the right article.

As a general rule short of running new grounded wire. It is acceptable to install gfci protection on all non grounded circuits within the house. This is considered by code to be an equivalent to a ground. However this is only acceptable to avoid running a new circuit to each outlet or switch. Which will eventually be the outcome.

Some areas of the world will not accept this as a substitute.

1.How To Add Ground Wire To Old House

Adding ground wire to an old house can be done a couple of different ways. This can be run with a seperate conductor from outlet box to outlet box. It can also go from switch box to switch box.

Note that is is just as time consuming as actually re-wiring and also just as expensive.

If we’re retrofitting a knob and tube wiring system with a modern ground wire, here are some general guidelines.

#1: Be sure the wiring is properly grounded to the metal water pipe of the house.

#2: Hook up the ground wire to a GFCI outlet that is on your main panel (the one with all the breakers).

#3: Run the wire from this GFCI outlet to your new grounding device. In most cases, this will be either a Ground Rod or an Earth Plate mounted on a concrete pad outside your house.

#4: Connect your new grounding device to the ground wire in step 3.

#5: If you have no additional circuits within the house that are not grounded, do not install gfci protection on any non grounded circuits (knob and tube wiring).

2. How To Add Ground Wire To Old House Main Ground

An expectable means of a system ground would be two 10 feet ground rods. These ground rods would be spaced ten feet apart. A piece of ground conductor #6 green awg would be connected between the two ground rods and then back to the main neutral connection of your home’s main panel.

Alternatively one can use a ground plate. This ground plate must be standing upright. it must also be dug to a depth of 600 mm or 2 feet. A piece of number #6 green must be installed from the ground plate back to the main panel.

how to add ground wire to old house

3. How To Add Ground Wire To Old House Branch Circuits

One way to add ground wire without fishing is to install a ground fault circuit interrupter (GFCI) in the circuit.

A GFCI will detect when there is an unintended current path and interrupt the flow of electricity by shutting off the power until a repair or replacement can be made.

A GFCI is necessary for kitchens, bathrooms, garages, and crawl spaces in new home construction. It’s also recommended for most non-commercial buildings over 30 years old.

The gfci can act as a false ground and is an acceptable means.

4.How much does it cost to install a ground wire in a house?

We’ll use our example of a 3 bedroom house with old non-grounded circuits to calculate the cost. The calculation will be based on the square footage of each room in the house and then it’s just a straight multiplication to determine how much it would cost.

The average cost for installing a ground wire is between $1,000 and $2,000. This doesn’t include any extra labor or equipment costs.

5. Is ground wire necessary?

Ground wire is not required in all cases. Sometimes it is possible to install a gfci outlet on non-grounded circuits and rely on that outlet in place of a ground wire. This will be acceptable by code as an equivalent to a ground.

However, in some places it is illegal for this to be done. There are three main reasons for this:

1) All wiring must have a ground loop to prevent shock hazards

2) Ground wires must be at least #14 gauge in size

3) The grounding electrode cannot be connected directly to any other conductor such as the neutral or hot wire

Consult with your local electrical inspection authority for rules an regulations

6.Do all homes have ground wire?

No, not all homes have ground wire. Some areas of the world will not accept this as a substitute.

If your home does not have a ground wire you can still install gfci protection on every non-grounded circuit, this is considered by code to be an equivalent to a ground.

Older wiring must be replaced to bring it up to date with a ground.

7.Is GFCI as good as ground?

GFCI protection is considered by code to be an equivalent to a ground.

If your property has metal wiring, you need to add ground wire or install GFCIs on all non grounded circuits in the house.

The problem with GFCI is they are not as reliable and safe as a grounded circuit. They can trip off when there’s no power. This could lead to nuisance tripping .

As a general rule, it is acceptable to install GFCIs on all non-grounded circuits for the purposes of code compliance, but again, keep in mind that this does not offer safety benefits like grounding does.

8.Can I run a separate ground wire?

This is a question that comes up frequently. In the United States, it is acceptable to install gfci protection on all non-grounded circuits within the house. This is considered by code to be an equivalent to a ground wire.

Some areas of the world will not accept this as a substitute for running new grounded wire.

One can run a seperate ground wire to each outlet and switch. This would need to be a minimum of #14 gauge. However at this point you might as well just run new wire and property ground the circuit.

9. Will GFCI outlets work without ground?

Yes GFCIs will work without a ground. That is what they are designed to do. They sense the unbalanced electricity between the 120 volt circuit and trip if there is any leakage of power. In a case where there is not grounded wire the gfci will protect you from getting electrocuted.

10.What is Ground Fault Circuit Interrupter (gfci)?

A ground fault circuit interrupter is a device which detects when a current flows through the neutral conductor. If a current flows in the wrong direction, it will shut off automatically and stop any further flow of electricity.

The device is used to protect people from electrocution by detecting if there is a potential problem in an electrical system. Ideally it should be installed where there are high-risk locations such as bathrooms, kitchens, garages, and basements.

11.Why should you add a ground wire?

The reason many people don’t add a ground wire is because they think it’s unnecessary. But before you start running a new grounded wiring for your outlets, read this post to find out the benefits and how easy it is to add a gfci protection.

GFCI safety switches

Should you install GFCI protection on all of your circuits?

This question may seem strange, but in recent years, many homes have been wired with GFCIs. The process of installing these safety switches can be confusing and tricky. If you’re not familiar with the concept or if you want to make sure that every non-grounded outlet is protected, then we’ll show you why adding GFCI protection is a smart choice.

First, let’s define what a GFCI is. A GFCI (Ground Fault Circuit Interrupter) device detects when there are two conductors that are touching each other on the same circuit – which can be caused by an electrical fire or shock. When this happens, it automatically disconnects the current in order to avoid harm from happening to someone nearby – like your child. In order to prevent electrical fires from happening, codes require that every household have at least one GFCI installed

12.The work installing the gfci is not safe.

The work installing the gfci is not safe.

Personally would never install a GFCI on a non-grounded circuit as you will eventually run out of circuits to install them on. Always contact your local licensed electrician to help you with projects like this.

13.Proper way to install gfci protection.

There are two ways to install a GFCI. The first is to install a GFCI on an existing non-grounded circuit. This will prevent the flow of electricity in the event of a short circuit, and is considered by code to be an equivalent to a ground. However this is only acceptable to avoid running a new circuit.

The second way is to install a GFCI on all circuits in your house that are not grounded, which requires you to run wire from each outlet or switch into the box where the GFCI will be installed.

14.What can I use if I don’t have a ground wire?

If you don’t have a ground wire and you need to install Gfci protection, then the solution is to install a Gfci on each outlet or switch. This will not run new grounds in your house as it is considered by code to be an equivalent of a ground. This will be acceptable if one were not available.

15.Can you just add a ground wire to an outlet?

The answer is yes, you can. However, this is not the preferred solution and it is not required by code in order to be compliant. If you do this it will be considered an equivalent to a ground and by code it does not need a permit.

However if your goal is to avoid running new grounded wire in order for your outlet or switch to have gfci protection on all non grounded circuits then you should install gfci protection at each outlet or switch location.

If you are installing gfci protection from the breaker box, there will be a requirement for a permit and the only requirement will be that all wires from the breaker box must terminate in a terminal strip within 2 feet of the panel and that they be bare copper.

16.Where do you connect ground wire if no ground?

It is not required by code to connect ground wire in a home unless it is already there. If the circuit or outlet has no ground wire, then all you need to do is attach gfci protectors to all non grounded outlets or switches within the home. This will provide protection from any potential shocks that may result from an electrical current running through them. Be sure the gfci protectors are plugged into a wall outlet with a ground wire.

17.Do all houses have grounding rods?

No. Not all houses have grounding rods in them. This is a method to avoid the need for running new grounded wire and instead use gfci protection devices on all non-grounded circuits within the house.

18.Can I use rebar as a grounding rod?

In theory, no. But in practice, this is not a recommended option because the rebar will not have enough surface area to provide adequate current protection. Rebars are also very heavy and difficult to install.


Ground Fault Circuit Interrupter (gfci) protection is a safety device that protects electrical circuits from overheating and catching on fire. Most homes have a built-in gfci, but if your home does not, it is a relatively simple process to add a new gfci. However, the installation of this device needs to be done by professionals and the work is not safe.