If you have the skill to do so you can save yourself a great deal of money by wiring or rewiring lights in your own home – it’s a comparatively basic procedure, and one that a confident homeowner may feel that they can take on without the assistance of a professional electrician.
Of course, there are a number of safety concerns that surround such a project. Electricity and live wiring is not something to experiment with, so if you have never undertaken such a task before do not even consider doing so without the help of a qualified tradesperson.
Check websites such as Electrical Safety First too, to ensure that you are appropriately qualified, and remember that you should be declared competent to complete such work in the eyes of the law.
If you are clear of red tape, however, read on for a how-to guide to writing a light switch or fitting in your home.
Understand the Flow of Energy Around Your Home
You should also be aware of the power sources and energy flow throughout your home. Learn the location of all trip switches and circuit breakers, and be fully aware of the maximum voltage that any outlet will allow. This will prevent any unfortunate events further into the experience of wiring a light as you will not be pushing the limits of your electricity supply further than they can tolerate.
Acknowledge the Existing Light Fittings
If you’re going to remove all the existing fittings and fixtures in your home in order to replace the wiring, always make a note of the where they were to begin with. Whether you return the original equipment or replace it with new materials, the chances are that you will be working in the same vicinity.
If you are looking into rewiring a light switch, always make a note of which wires were connected to each other – especially the colours of the live wires. Mixing and matching, or making a mistake, can just create more work at best as you blow a fuse or trip the electricity throughout your home, or could even cause a shock at worst. Make a diagram of the fitting if this helps.
Removing the Existing Fitting
First thing’s first; turn off every possible source of power to your light fittings before you begin taking them apart – this is basic electrical safety. Pick up a voltage tester, which can be purchased from any reputable DIY shop, to perform an extra safety check.
This tool should confirm that the circuit is in no way live. Once you have done this, open the cover to your lighting circuits (this is called the ceiling rose) you will be faced with a number of cables that need to be replaced and re-applied.
Identifying the Circuit Type
You will be able to tell what kind of circuit you are working with by assessing the number of cables that enter the ceiling rose.
If one cable enters the ceiling rose, you have Junction Box Wiring.
If two cables enter the ceiling rose, you have a Loop In Circuit. This will mean that you have a circuit cable and a switch cable.
If three cables enter the ceiling rose, you have Loop In Wiring. This will mean that you have two circuit cables and a switch cable.
Wiring the Light
NOTE – a working knowledge of the colouring of UK wires is essential for this task. If you require assistance, read our guide on this subject here.
If you have junction box wiring, run cable that contains two cores and an earth wire from a three terminal junction box above the rose. Having done this, connect the brown core to the live terminal of the rose, the blue core to the neutral terminal, and the earth wire (usually protected by a green and yellow sleeve) to the earth terminal.
If you have a loop in circuit, use a four terminal junction box above the rose. You will have three cores from this box – live, neutral and earth – which are to be connected to three different terminals. This will obviously leave you with one unused terminal, which we’ll get to shortly.
Next, take the brown core of the switch cable and connect it to the live circuit, attach the earth core of the switch cable to the earth circuit, and take the blue core from the switch cable and attach it to your unused fourth terminal. You will then need to add a fourth cable in order to provide your light with power; connect the brown core of this cable to the blue switch, the blue core to the neutral circuit, and connect the earth core to the earth circuit.
Once you have done this, you should be ready to switch on the mains power again and text whether the wiring has been successful using your voltage tester – if so, switch off at the mains once more and replace the light fixture.
Is Wiring a Light Easy?
That depends on your definition of ‘easy’. A qualified and experienced electrician will consider this a very small job that they could perform in no time at all on their way home from a day’s work, but if you have no previous experience in working on such a project you are placing yourself and your home at risk.
Is Wiring a Light Dangerous?
If you don’t know what you are doing then yes, very much so. Do not attempt to tackle this task yourself unless you are confident in your electrical capabilities. If in doubt, consult a professional.
What Happens if I Wire My Light Incorrectly?
You will trip your power socket at best, but the consequences could be considerably graver, with an electrical fire a very real possibility.
How Do I Know if a Socket is Active?
Always use a voltage tester before you even consider touching the wires.
What Colour is the Live Core?
Brown – unless you have an old-style plug, in which case the live core will be red. These old-fashioned plugs are outdated and now illegal, so if you are confronted with wiring of this nature call in an electrician to replace them at your earliest convenience.
What Colour is the Neutral Core?
Blue – but again, outdated and old-style plugs will have a black neutral core. As with the live core, seek professional assistance if you have a black core as opposed to blue, as this is not safe.
What Colour is the Earth Core?
No matter how old your wiring is, this core will always be yellow and green.
I Opened the Ceiling Rose and There are More Wires Than You Listed?
This suggests that a previous owner of your home has wired an additional light into the same ceiling rose, possibly from a neighbouring room. If you are unsure of how to proceed, call in professional assistance.
I Want to Do This Myself, but I Don’t Understand Your Instructions
That is no failing on your part – wiring a ceiling light can be a complicated process if you are not familiar with the technical aspects of such a process. It is strongly advised that you seek the advice of a professional in this instance though, as electricity is not something to be toyed or experimented with.