Colour Temperature - With conventional lamps, choosing the “colour of light” emitted by a lamp was not a choice that was generally made. With some LED products, there is a choice of colours, choosing a colour will set the mood of your space.

Correlated Colour temperature (CCT) in lighting describes how the colour of the light appears from a lamp, measured in kelvins (K).
 
Imagine a scale from 1000K (very red)  to 10,000K (very blue)  (actual scale is wider).  The higher up the scale you go, the closer the light resembles blue daylight.

Confusingly, colour temperature does not describe the actual temperature of the lamp itself but the colour it produces and counter intuitively; the higher the colour temperature the “cooler” a lamp will look. 

Kelvins Type  
1,000K Candlelight Red/Yellow Very Warm
2,700K-3,000K Conventional Lamp - Yellow Warm White
4,000K-5,000K Halogen/CFL - Blue Cool White
10,000K Blue Sky - Blue Very Cool

Put simply, colour temperature is based on how the colour of a heated metal changes as its temperature is increased - turning from red to yellow then blue.  You can then determine the temperature of a heated metal by its colour.  This range of colours at different temperatures has become useful for describing the colour tint of white light.  The colour of light from an LED lamp is approximated or “correlated” to this scale.      

Warm white or cool white?

There are no rules - the choice is about personal preference and use. If you like the traditional yellowish colour of a conventional lamp then warm white around (2700-3000K ) would be the ideal choice, this is the most popular choice for homes. If you want a modern, clean look, you may prefer the cleaner, brighter feel of a cool white lamp (4000-5000K). 

In commercial applications choosing the right colour temperature is important and will depend on the mood you want to create and the products you are promoting - for example freshly baked cookies and bread may look better under a warm white light. A cool white light may not make the product look as appealing but it would be a good idea to do some trailing to see what works best.

Where can I use them?

Below are some common areas where the different colours are can be used:

  • Warm white – living room, bedroom, hallway
  • Cool white – kitchen, study, bathroom, cupboard, office, retail

 

Mix and Match

There is no reason why you could not have a mixture in the same setting. For example, warm white for the main room lighting and cool white for task lighting over work areas. 

How do I know which one I am buying ? 

All Integral retail packs have a clear icon and colour temperature indicated on the packaging. In addition, each lamp will have the colour temperature printed on the base e.g. " 3000K". 

Due to variations in the manufacturing process and different measurement methods you should consider buying the same model of LED lamp for all the fittings in an area or room. It would also be a good idea to buy spares – as LED technology (as with other technologies such as mobile phones) is always improving and changing.