When you’re installing new switches and sockets, you will usually find a disclaimer telling you the importance of grounding everything you set up. That said, there can be a lot of confusion on why we ground our electrics in the first place.
Unscrewing a switch plate will reveal a number of cables, and, in most modern homes, one of these will be a ground wire. Grounding light switches have become commonplace, used as a preventative safety measure.
It is perfectly legal to wire a light switch without the inclusion of a ground. Dimmers will require a ground wire but traditional toggle-type switches will not. Omitting a ground wire on any switch is not recommended.
What Happens If I Don’t Ground A Light Switch?
Before we get into grounding and its importance, let me quickly explain what the ground wire does.
Electrical charges are naturally attracted to conductive surfaces like metals, which can then be passed onto our bodies. This phenomenon is known as electric shock.
The purpose of a ground wire is to give that excess charge an alternative route that keeps us safe from severely dangerous electrical shocks or potential fire.
To achieve this, the ground wire extends deep into the earth below your home. The wire takes charge off the surface into the ground and releases it there safely.
Now, as you understand the purpose of grounding, let’s see what happens when you don’t wire the ground cable.
The plug without a ground cable is dangerous because there is no alternative path for the charge to escape from the circuit.
As a result, the conducting area is under the voltage. You then run the risk of coming into contact with the deadly excess charges that emit from power outlets.
As you can see, the ground wire only provides benefits to your circuit.
If you have the option, then wiring up a ground cable really is a no-brainer.
Especially, using the switch with wet hands like in a bathroom or kitchen, you can save yourself many issues.
Part of the ground’s role in the circuit is also forcing the breaker to trip when there is an electrical fault. Without this, the dangerously high current wouldn’t be halted going into the appliance.
Is Ground Wire Legally Required?
While I said that a ground wire is a no-brainer, the legal requirements and restrictions vary nationally.
Although many families live safely without grounding their light switches, many inspection services hold a much stronger opinion on their omission.
For example, to meet building regulations or to pass an electrical inspection on a government/council-owned building, all light switches will require grounding.
Whether the task becomes the responsibility of the landlord or homeowner will vary on a case-by-case basis.
But you will struggle to convince local authorities that your own wiring is non-hazardous if they find the switches are not grounded.
Metal Vs Plastic Box: What Are The Grounding Requirements?
Particularly with old houses, replacing a light switch can provide more problems than you would have initially thought.
If your switch uses a metal box, it must also be grounded, whereas non-conductive plastic casings will not.
The most common problem is that new light switches often do not come with an earth wire.
That is where we should compare metal and plastic switch plates.
Metal faceplates are particularly useful for older houses. Most old connections will have an earth wire but no backbox to connect to. In this case, you can connect the earth to the backplate.
Plastic faceplates are inadequate for earthing purposes. The same situation would require a connector block that the wire could then be connected to.
Metal switch plates also have a distinct advantage over plastic plates in their durability.
When screwing in the plate, even slight over-tightening will often crack plastic plates, exposing the internal wiring.
While metal switch plates are often the more expensive choice, the premium price tag goes towards an easier installation – especially for older builds – and a clear display of quality.
There is also an alternative to a physical ground cable. Lots of modern switches have a ground screw that diverts the excess charge through it.
The bottom line is, as long as there is metal-to-metal contact between your ground and the switch covering/box, your light switch will be grounded.
Do Smart Switches Need To Be Grounded?
Smart switches are still in their infancy, but they allow us to control our lighting from the tap of a phone screen, the press of remote control, or our voice alone.
For the most part, smart switch installation functions similarly to that of a regular light switch.
Suppose you make a note of how your current switch’s cables are connected. In that case, the new installation is much easier as the cable configuration is identical.
However, with smart technology being such a new integration in our homes, most smart switches will require a neutral wire – something hard to come by in houses built before the 1980s.
There are some exceptions to this rule. These smart light switches are noticeably higher in price to compensate for this easier installation route.
Regardless of the switch type, whether it is a smart or “dumb,” the same grounding rules apply.
As I said before, grounding is highly recommended as it is a key safety measure that will be noticed in an inspection or if you are looking to meet building regulations.
How To Ground A Light Switch Without Ground Wire?
I have briefly mentioned above that there is one alternative to using a ground wire found in some homes.
Some light switches will not have a ground cable, and in that case, the electrician has opted to use a metal screw as bare ground.
It is crucial to ensure your new switch plate accommodates for this grounding screw as connecting without this is not recommended.
In numerous instances, chiefly, when dealing with older houses that use metal boxes, the box itself may be grounded in this way without a cable.
As long as the metal box itself is grounded, the circuit will be grounded if there is a metal to metal contact.
Again, if the box is not grounded, you run into the same disclaimer encompassing this article.
Personally, I would always recommend grounding your switches as moisture/damp hands can result in a lethargic shock without the safety measure in place.
So there you have it, your home may opt for screws, cables, or grounded boxes, but your switches should all have a ground outlet to ensure your safety is secured.
Without it, you put your body at risk of completing a circuit holding lethal electrical charges.
Have you found that your switches aren’t grounded? Need a hand making sure you pass an upcoming inspection?
Leave me a comment, and we can have a chat all about it!