Last week, I asked the new apprentice electrician at work to grab me the 1 gang 2 way light switches. He looked at me as if I had two heads and just spoke in some made-up language. Then I explained what 1 gang and 2 gang light switches mean and he realised it’s pretty straightforward once someone has explained it in plain English.
This got me thinking that there must be lots of people who are confused by this funny lighting lingo. This post will explain in clear plain English what the terms 1 gang 1 way, 1 gang 2 way, 2 gang 1 way and 2 gang 2 way mean as well as a few other common terms. I’ve also added some comparison tables for costs of switches to help readers decide what their best options are!
The number of gangs a light switch has simply refers to the number of physical switches on one plate. The number of ways refers to the different operating functions each switch has. We are most likely to find a two-way switch at each end of our hallway.
That is the concise explanation in handy quick read form. Don’t worry if it’s still a little confusing we’ll go on to break it down further so you know exactly what light switch you need. If you are looking for info on lighting motion sensors, you can find that in our article linked here.
Let’s start with breaking down what a light switch gang means then we’ll move on to what light switch ways are referring to.
One, Two and Three Gang Meaning for Light Switches
As we mentioned, the number of gangs refer to the number of switches on one plate. The most common type of switch in our houses is a one gang switch. This is a simple light switch as pictured below.
We can see that there is just one switch on the backplate. This would be known as a one gang switch on a single backplate.
When we talk about the plate we are referencing the plastic bit at the back that the screws are in. This is what we would call a single size backplate
These single backplates are all the same size. The construction industry got together and determined that this would be the universal size used for a single plate (FYI: it’s the same size as a single socket). If you buy any single plate size switch it will fit as a replacement where another single size plate once was.
It makes logical sense that if we have one switch for a one gang light switch we would expect to see two switches on a two gang light switch, and that’s exactly what we get. (I would always advise buying good quality branded switches like my preferred ones linked on Amazon here.)
2 Gang Light Switch
Below is a photo of a 2 gang light switch. It simply means there are two switches positioned next to each other on the same backplate.
When it comes to gangs on light switches it really is that straightforward. In domestic properties, we will most often find one and two gang switches.
Occasionally we will find 3 gang or 4 gang switches in our homes (usually in a kitchen where we need to have several lighting controls all in the same place)
3 Gang Light Switch
The image at the start of this post, which I’ll put below as well, shows a 3 gang light switch.
We can see we now have three switches on one backplate. This means we can control 3 different lights from one position in our home. This 3-gang switch on amazon is a good option in most use cases.
It’s not that obvious from the photo but there’s something we need to be aware of. As we now have 3 light switches on the same plate the size of the backplate does sometimes increase. In the photo above it is no longer a single backplate it is now a double backplate.
Worth noting we can get 3 gang switches on a single size backplate as the photo below taken from Screwfix shows.
As with single plate sizes, the industry got together and agreed on a size for all double backplate sizes. All double backplate size switches are interchangeable (this also happens to be the same size as a double socket)
The reason the industry has standardised these sizes is it makes replacing electrical accessories (such as light switches) a much easier job. The backbox is buried in the wall which the plate can screw into. There is no need to change the backbox when changing the light switch as the size is standardised.
In commercial premises, we can go crazy about the number of gangs, especially in large open floor spaces. We can have dozens of gangs on each backplate. However, for the purpose of simplicity, I’ll stop at 3 gang.
Dimmer Switches have Gangs
We’ve used common light switches in all our example photos above but the exact same rules apply to dimmer switches. A dimmer switch is still just a switch so we can have a 1 gang dimmer switch, 2 gang dimmer switch and so on.
Below is a photo of a 3 gang light switch but one of the gangs is a dimmer switch.
Pull Cord Light Switches (Common Bathroom Light Switches)
To round off our understanding of light switch gangs we should briefly mention pull cord switches. These are the type of switches most commonly found in bathrooms. A basic type from a good manufacturer like this one on amazon is all most people need, there’s no need to break the bank. The switch is on the ceiling and a rope hangs down so that our wet hands don’t go anywhere near the electricity.
Although technically the pull cord switch imaged below could be considered a one gang switch, I’ve personally never seen a two gang pull cord switch and a quick google demonstrates to me that they are not easy to find.
If you searched for a pull cord light switch the image below is what you would find.
Hopefully, that has explained the differences in the gangs of the light switches. Sorry if I’ve laboured a point but I’m always told I have a habit of explaining too fast so I’ve tried to break it down as much as possible.
Now we understand light switch gangs we can look at what we mean when we talk about the number of ways a light switch has!
Also See: Can You Use Indoor Lights Outside?
One Way Light Switch Explanation
A one way light switch is the most basic type of light switch. It means the light switch has one primary function, the switch can be flicked downwards to make the light come on and flicked upwards to make the light switch off. One way switches, such as these on Amazon, are commonly found in bedrooms as there is often only one doorway in and out of the room.
Anywhere in your home, you have one doorway, such as a bedroom or living room, you are likely to find a one way light switch. This is because you are going to leave via the same door you entered the room and therefore we are going to operate the exact same switch to turn the light back off as the switch we used to turn it on.
This talk of doorways may be a little strange but stick with me as it is the best way to explain lighting ways.
The photo below shows the wiring of a one way light switch I have taken off the wall to demonstrate. The wiring in the switch is as simple a circuit as it gets. The switch closes (or turns on) to make the circuit complete and the switch opens (or turns off) to break the circuit and turn the light back off.
As we can see there is power in and power out. A very basic light switch as described above.
There is one switch (1 Gang) on the backplate, and it is a one-way switch. Therefore we refer to this type of switch as a 1 gang, 1 way light switch (on a single backplate). See how it all starts coming together!
Although the switch is basic and simple the circuit wiring isn’t. This post is to get an understanding of the jargon only. There are many ways to wire a lighting circuit so I would always advise getting a qualified electrician to do any electrical work for you.
Two Way Light Switch Explanation
Two way light switches are used when we need two different switches to operate the same light. The most common place we can find examples of two way light switches are at opposite ends of a hallway. Any room we may enter through one door and exit through a different door usually have two way light switches.
2 way light switching is slightly more tricky to understand but it shouldn’t be too difficult with an example (hopefully). Here is an example of a 2-way switch available on Amazon.
In my hallway at home, I can enter through the front door and then exit the hallway into the kitchen and bedroom out the back. The great thing is I can turn the hallway light on when I enter through the front door via the light switch positioned beside this door. As I exit the hallway into the kitchen at the back I can turn the hallway light off via the switch positioned beside this kitchen door.
Sticking with our example, in the morning I can enter the hall via the kitchen door and turn the hallway light on, I can then exit via the front door and turn the hallway light off.
We need the two light switches to be able to operate the hallway light in whatever position is required.
Try this at home by switching the lights. You may have not taken much notice, but you probably have hallway lights like this, or perhaps a light switch at the top and bottom of the stairs that controls the same light.
We can see that flicking the switch down no longer definitely means the light comes on and flicking the switch up no longer definitely means off. It depends on the operation of the other light switch as well.
We need the two different light switches to operate in different ways. This is where 2-way lighting comes in.
A 2 way light switch can be paired with another 2 way light switch at opposite ends of the room and they both work together to control the same light.
The image below shows the wiring at the back of a two way light switch. This is one I have taken off the wall at home to demonstrate, all in the name of science!
We can see there are more cables this time and the wiring for two way lighting is more complicated. The additional cables are known as ‘strappers’ and they allow the two light switches to communicate with each other (this isn’t technically true but helps explain the point I feel)
The purpose of this post is not to explain how to wire the lighting as I would always advise getting an electrician in to complete any electrical tasks.
The image above has 1 switch on the backplate (so it is a 1 gang switch) but it needs to work in conjunction with another light switch at the opposite end of the hallway (so it is a 2-way switch) This means that if ordering this switch we would ask for a 1 gang, 2 way light switch.
Hopefully, readers can see that the gangs and the ways of light switches are separate issues to consider. We can have a 1 gang, 1-way switch or a 1 gang 2-way switch. They are independent of each other.
Intermediate Light Switching
Intermediate light switches are used when 3 or more light switches are needed to control one light fitting. A place in our home we may find intermediate switches would be in a large bedroom with one light switch beside the door, one next to the ensuite door and one switch by the bed, all-controlling the same light in the middle of the bedroom.
2 way light switches work perfectly when we have two separate light switches controlling the same light. If we need more than two light switches, like in the example above, then we need to start adding intermediate switches.
We can add as many intermediate switches as necessary.
Below is a photo of the rear of an intermediate light switch. I don’t have an intermediate switch in my flat I can take off the wall so I’ve borrowed an image from Screwfix. Readers can see we now have 4 terminals at the back to secure the cable into.
The same rules regarding gangs still apply, so the above image is a 1 gang intermediate light switch.
Wiring for intermediate switches starts even more complicated again, so even the keenest DIYer should contact an electrician (as with all electrical work needing to be done).
Cost Comparison For light Switches
Many electricians choose to stock their vans with two-way lighting rather than one way as the costs are pretty similar.
A 2 way light switch can be used as a replacement for a 1 way light switch. The same is not true in reverse, if we need a 2 way light switch we cannot use a 1-way switch, we must leave the job to go and buy the correct 2-way switch.
Light Switch Cost Comparison
| Brand | Type of Light Switch | Cost (£) |
|---|---|---|
| MK | 1 Gang – 1 Way | 1.69 |
| MK | 1 Gang – 2 Way | 1.81 |
| Mk | 2 Gang – 2 Way | 3.36 |
| MK | 3 Gang – 2 Way | 6.51 |
| LAP | 1 Gang – 2 Way Dimmer | 8.05 |
| MK | 1 Gang – 2 Way Dimmer | 26.49 |
We can see from the table above that the difference in cost between a 1 gang – 1 way and a 1 gang – 2 way light switch is less than 20p. For this reason, it is often easier and more cost-effective to order a bulk lot of the 1 gang – 2 way light switches.
Final Words
Hopefully, that’s cleared up everything and you now realise what 1 gang light switch means and what 2 gang light switch means. If you would like to read our article on the time it takes to replace a light I’ll link it here
