Tag Archives | LED

LED lighting – what to look for, how to choose

LED lighting has improved immeasurably in the last few years.  Gone are the days of blue light at a high price – LED lighting is now warmer, softer and much more affordable.

Part L, the Building Regulation that covers energy efficiency, states that 75% of fixed lighting within a new build or refurbishment must provide at least 48 lumens per Watt, and 400 lumens per fitting.  Lumens measure brightness.  So it is effectively saying that, for the lighting that’s fixed in your home, you must get a decent amount of brightness for the amount of electricity you are using.  Using LED lighting is a very effective way to achieve this.  But what to consider when choosing a brand for your spotlights?

Colour consistency

I’m sure you’ve all been in a shop, restaurant or someone’s home and noticed one pink spotlight amongst the others.  Or perhaps one that’s slightly green?  Maybe you have one yourself at home.  Good quality brands of LED lighting do not vary in colour in this way.

You probably know that lights in general tend to be available in warm white and cool white.  The colour temperature of light is measured in Kelvins.  Warm white is 2700 Kelvins; cool white is 3000 Kelvins.  While these measurements sound quite precise, in fact a 2700K light could have a pronounced pink or green tinge to it, and still be correctly categorised as 2700K warm white.

So, what we are looking for is manufacturers that have a more limited definition of what measures as 2700K (or 2400K, or 3000K, etc). In other words, manufacturers that categorise(‘bin’) their LEDs based on a more limited criteria.  This variation can be measured as MacAdams ellipses.  If the light is classified (‘binned’) as 2700K, to an accuracy of 3 MacAdams ellipses or less, you can be confident that all the lights from that manufacturer classified (‘binned’) as 2700K will look the same colour to the naked eye.

Colour rendering

Colour rendering measures how accurately colours appear under a certain light compared to daylight. Many cheaper LED light fittings have terrible colour rendering, particularly for reds.  Your reds may look brown, your blues may look grey.  So what we are looking for here is brands that have good colour rendering.

This is measured on the Colour Rendering Index, which compares the performance of the light against daylight.  It is marked out of 100. Above 90 is excellent.  80+ is good.  Anything below 80 is not going to reproduce colours accurately and is best avoided in your home.

You also have to be careful that the manufacturer has included all 14 colours when they state their CRI score for a particular light. It is possible to score only on the first 8 colours and state that the light is a certain CRI score, when if the last 6 colours, which are more challenging, were included, it would be much lower.

Which LED lighting brands?

You can use the above criteria to consider any make of LED bulbs or spotlights. Brands I have personally come across that meet these criteria include EcoLED, Orluna and John Cullen. Of course, good quality costs more, but you get what you pay for – better technology, a better result, a better home. Along with all LEDs, the extremely long life of the bulb (up to a decade!) means you can buy once, and save many times over with the energy savings and replacement savings compared to halogen spotlights.

With the above information, you can make an informed choice, rather than kitting yourself out with cheap LED fittings and then being disappointed with the result and paying more in the long run.

Plug-in lighting

Note that plug-in lamps are not covered by Part L.  Most plug-in lamps, and some ceiling and wall fittings, take traditional bulb sizes.  While standard incandescents are no longer available, the next best solution – aesthetically – for fittings that take E27, E14 (screw-in) or B22 (bayonet) bulbs at the moment is reduced wattage Halogen, such as these from Phillips.

Whether it’s LED lighting or not, always put your lights on dimmers if you can, make your spotlights directional (usually aimed at the walls) rather than pointing directly down, and please don’t put them in a grid on the ceiling!  More about this in a future post.

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