Downlights: Mains Voltage (230V) vs. Low Voltage (12V) vs. LED (Light Emitting Diode)

“What is the best type of downlight? Mains, low voltage or one of these new LED’s?”

This is one of those typical questions that I expect to have to answer almost daily. And our lives would all be a lot easier if there was a simple answer to this question but I’m afraid there are number of different aspects one needs to consider when making this decision for your home. Namely: safety, cost, legal considerations and personal taste. In this section I will begin by explaining the difference between the two types of halogen lamps, highlighting the pros and cons of each, and then move onto the modern LED equivalent before finishing off with a summary in the form of an easy to use reference table.

MAINS VOLTAGE vs. LOW VOLTAGE

Before we begin you will need to learn how to differentiate between the two “caps”. The cap is the part of the lamp that either pushes or screws into the light fitting. The modern 230V halogen downlight will use a “twist in” GU10 cap while its 12V counterpart will have a “push in” GU5.3 cap, more commonly known as a MR16 cap.

Having a lower voltage than the GU10 lamp, the MR16 fitting will cause a less severe shock and, while still painful, is less likely to induce a serious injury. For this reason most under cabinet lights and other fittings which are used at lower levels are manufactured to be used in conjunction with a transformer which lowers the voltage of the electricity being fed to the lamp.  I personally prefer the use of 12V fittings in wet rooms, such as baths and saunas, as a faulty fitting could allow electricity to flow through any condensated water and potentially shock occupants. However please don’t let this put you off using 230V fittings in the rest of your home. Reputable manufacturers take every possible precaution to make sure the modern halogen downlight is safe so the risk of coming into contact with a live faulty fitting, 230V or otherwise, is minuscule. The drawback of the MR16 halogen lamp is that it tends to allow a lot of its heat to escape out of the back of the fitting and can become a fire hazard if fitted anywhere near timber or other flammable materials. Although this can be combated with the use of the more expensive aluminium backed MR16 lamps, they should probably only be installed in a property where you will be changing the lamps yourself as tenants and janitors will invariably just put in whatever is cheapest . 

Unfortunately the initial cost of installing 12V downlights is substantially higher than installing 240V downlights. This is due low voltage lamps having to make use of transformers which are largely comprised of copper, a metal which is constantly undergoing price fluctuations. When it comes to transformers, you really do get what you pay for so, if you decide to go down this route, please be willing to spend a little extra cash on a trusted brand. Otherwise you might find yourself either having to constantly replace them or having to put up with a very annoying humming sound. Over the long term however, the low voltage lamp does pay for itself in that it is much cheaper to replace and also often has a life approximately twice that of their 230v counterpart.

The laws on what type of lighting can be used and where is changing yearly and should always be consulted before making any plans. These laws may sometimes seem a bit over the top but adhering to regulations is extremely important. Not only does it keep you and yours safe but it also keeps building inspectors happy and prevents a big loophole for insurance companies to deny pay-outs should any damage occur due to an electrical fault. Therefore ensure that you always employ qualified electricians who can produce legal paperwork and certificates for all work they undertake in your home. See my guide on “Choosing an electrician” for further details. However, as a rule-of-thumb reverence, I have summarised the current legislation on using lights in the bathroom under the heading “Locations Containing a Bath or Shower”. These guidelines allow light fittings with different IP ratings and voltages to be mounted throughout the bathroom depending on which zone they are installed, however most electricians and interior designers will insist on a low voltage downlight fitting with the highest available IP rating available being installed throughout the bathroom. Not only does this make them safer but also means that all the fittings will match both in looks and light output.

HALOGEN vs. LED

The 230v and 12v halogen lamps are great light sauces but both have two major downsides that you should be aware of. Firstly they have a very short lifespan of approximately 1000 to 4000 hours depending on manufacturer/voltage and therefore need to be replaced often. Meaning you will continually be forking out cash and climbing ladders to keep them all working. Once they are installed they also use a considerable amount of energy (the standard being 50watts per lamp) and overtime will cost you a small fortune. The solution is to use a LED lamp from a reputable manufacturer. Today’s LED lamps have on average an estimated life of 50,000 hours and only use 4 or 5 watts of electricity. This means massive savings of both time and money in the future. As an added bonus they don’t rely on halogen gas and therefore are available in three different shades of white irrespective of the voltage they are being supplied. The three shades being Warm White, Cool White and Natural White (aka Daylight).

Sadly the initial cost of installing these lamps is currently quite high and thus deters a lot of uninformed customers. However this high cost is due to the energy saving technology that can cut the electricity being used by 90%! The overall savings are easily illustrated when we use my “LED Money Saving Calculator” on hypothetical new-build home where the owners, Mr and Mrs Smith, decided to install ten LED lamps over ten standard halogen lamps and managed to save themselves an average of £100.60 per year. These calculations were based on an electricity cost of 10p per kilowatt and 5watt LED (£18.00) and 50watt halogen (£1.75) lamps, which were being used for 5hrs a day, 48 weeks a year (the Smiths are fortunate enough to be able to spend their full 4 weeks annual leave each year on a remote island). You can see the LED quickly pay for themselves.

In conclusion, I would strongly urge anybody who is building or renovating their home to use LED lamps if they can afford to do so. Even if you cant afford them now, make sure when you purchase your fittings that they can be retrofitted with LED lamps in the future (in other words, make sure that any if your fitting has a fire hat that it has enough room to take a LED lamp). If you still decide that you wish to go for the standard halogen, make sure to remember that the 230V gives a warm shade (orange/yellow) of light which I believe gives a more welcoming and comforting light while the 12V tends to be cooler (bluish) ideal for the more cleaner and “sheeker” feel. So make sure to choose your lamps accordingly.

	Mains Voltage	Low Voltage	LED
Voltage	240v	12v	240v or 12v
Cap	GU10	MR16	GU10 or MR16
Colour	Warm white	Cool white	Warm, cool or natural white
Transformer Required	No	Yes	Dependant on voltage
Initial Cost	£	££	£££
Average Lamp Life (Hr.)	1500 - 2000	3000	50,000
Lamp Cost	££	£	£££
Electricity Consumption	£££	£££	£

The views expressed are that of the author alone and do not constitute as advice. If you need formal advice on the particular facts of renovating a premises, please consult a qualified professional.