Following on from our blog on warm white vs cool white, we wanted to delve a little deeper into CCT, and answer some confusing questions around the use of the term CCT. As ever, if you are still not sure, please get in touch and we’ll do our best to help!
What is CCT lighting?
CCT stands for Correlated Colour Temperature - it is to do with the colour appearance of a light.
However, while you may think that a higher temperature equals a higher number, it’s the opposite way around. A bright (cold) white light would have a higher colour temperature than a warm white light. If you think about a flame burning, it’s usually red/ orange. As it gets really hot, though, it’ll become white/ blue. Lighting follows this principle so a higher number CCT is a ‘whiter’ light.
A common example is night mode on your phone. This will lower the CCT, making it a warmer softer light.
Confusingly, CCT is used in two different ways by lighting manufacturers. Either it can be used to specify a single CCT value, such as 3000K (equivalent to warm white), or to tell you that the light is CCT adjustable. In general if a light says CCT it means CCT adjustable.
For the avoidance of doubt, in this article we will refer to CCT adjustable but in our products, CCT means CCT adjustable, unless there is a value specified.
Do all lights have a CCT? What lights are not CCT?
No, not all lights have a CCT number, and all lights are certainly not CCT adjustable either. All white lights do, but coloured lights do not. You may have seen RGB lights (example here) - these do not have a CCT number.
Can you get lights that have multiple CCTs or are adjustable?
Yes you can. You may see these referred to as CCT adjustable lights or tri-colour lights. As mentioned above, they may also simply be called CCT. In general, if a light says CCT but does not specify a CCT number or description, it is likely to be CCT adjustable. However, we recommend always checking to confirm this.
Tri-colour lights have three set colour temperatures. These set temperatures vary from manufacturer to manufacturer, and sometimes even light to light, but are usually around 3000K, 4000K and 5000K. Giving you warm white through to a bright white light. Sometimes they will go as far as 6500K (daylight).
Adjustable CCT lights may refer to tri-colour, but may also refer to a light which can take on any CCT value within a range. This will work similarly to a dimmer switch, but is actually changing the colour temperature of the light, not the lux output (which is what dimming does).
What CCT number do I need?
If you’re trying to pick your preferred, single CCT for your new lights, we recommend reading this blog on warm white vs cool white. Another option is to opt for an adjustable CCT to save the choice!
Why should I choose CCT adjustable lights?
There are three main reasons we would recommend CCT adjustable lights:
1) One area where CCT lights really excel is ambience. This might be considered a nice to have but it makes a significant difference. For example, using a cooler white shade in the summer will help a space feel cooler, whereas a warmer glow in the winter will give a more cosy feel. It’s the same principle when wanting a romantic evening dinner versus plenty of bright light whilst cooking pr waking yourself up in the morning!
2) You're not sure which colour is right. If you opt for a CCT adjustable or tri-colour light, you don't have to choose immediately. Even if you want to go for one static colour in the end, you can play around with your electrician with the light in situ to choose the colour
3) You'd like to use the same light throughout the property to give a flowing effect, but might need different light colours. For example, a bright white for task lighting in the kitchen and a warmer white for the living area. Choosing a CCT adjustable light will allow you to use the same light and set the relevant CCT for each light.
Are CCT adjustable lights more expensive?
In general, the pricing is around the same, and more differentiated by other features of the product. Manufacturers are increasingly making CCT adjustable lights to save having to create multiple variants of the same light.
CCT adjustable and tri-colour lights are becoming the norm in downlights in particular, and there is no difference in the price between CCT and single colour. What you might find is there is a slightly higher cost to install, but this is typically minimal.
Globes and LED strips aren’t far behind - you’ll see many options here priced almost the same as their single colour equivalent. One of our best-selling products is the Luma Oyster light, which has tri-colour technology built-in.
Do I need special switches for CCT lights?
With CCT adjustable lights, you will need a mechanism to control the colour. The most popular choice is a standard dimmer switch or remote.
A stepped dimmer switch is often used with tri-colour lights.
Can CCT adjustable lights be installed as a single colour temperature light?
Yes, they can, which is why manufacturers find the colour temperature changing technology valuable to include. If a customer wishes to use an adjustable or tri-colour light as a single colour, this is possible.
Should all of my lights be CCT adjustable?
While you can choose for all of your lights to be CCT adjustable, it’s not strictly necessary. For example, if you have a room which has a combination of downlights and pendants, a good solution might be to have CCT adjustable downlights, but a fixed colour pendant. This is a combination which we commonly see, particularly as not all lights will be adjustable or compatible with globes that are.
Shopping for CCT adjustable lights
The use of CCT for multi-CCT lights does make shopping sometimes a little confusing. Most websites will filter their collections down to help you out here. For example, our collections can be filtered by colour temperature or adjustable CCT.
