Warm White, Cool White, Day Light? - Which colour temperature is right for you?

What is light bulb temperature?

Why should you care?

Ok, smarty, but which temperature is right for me?

Lighting Colour Temperature is something that many people overlook. Understanding lighting temperature is one of the cheapest and most affordable ways to improve the atmosphere in your house. In this article, we are going to explore what light bulb colour temperatures are right for your environment based on your needs. Changing the temperature of your light bulbs is one of the most affordable ways to improve the ambience and environment in your house.

Light Bulb temperature - that's hot.

When we refer to light bulb temperature, we're not actually talking about physical temperature caused by heat. The units used to refer to the colour temperature of a bulb or light fixture are "Kelvin" this is because kelvin is used to measure temperature universally. Say for example, that a bulb is 3500k, this means that the light it emits is equivalent in colour to that of something burning at 3500k. A bulb that has 3500k colour temperature has the same colour qualities as a star burning at 3500k, however not the same thermal temperature qualities, fortunately. Now, this is where it gets a bit confusing. Let's take some molten metal, for example, the metal burning at 6500k is hotter than the metal burning at 3500k. This is not the case when it comes to light bulbs and fixtures. When a lightbulb is 6500k we call it "Cool White" but when it is 3000k we call it warm white. Light bulb temperatures can vary from 1500k to 8000k and of course, there are some exceptions.

So, why should you care about light bulb temperature?

This is a very valid question, why should you care? When you walk into an office building or hospital one of the trademark features is many light fittings. What you'll also notice is that most of these lights give off a white/blue hue. This is because "Cool White" or "Day Light" gives off a better ambience that is conducive for working. Now, let's think about a cold winters day, you are sitting by a fireplace and you feel warm not only because the fire is letting off heat but it's also letting off a warm orange glow. Our perceptions of heat are programmed by things like firelight and sunlight. Fire gives off an intense warm heat. There is a study that found that people placed in environments with more "cool light" felt cooler and people in environments with warm light felt warmer.

Again going to the fireplace example, our perceptions of what is warm and cosy are that of an environment with warm light. And on the other side of the spectrum, an environment with similar light to that of the outdoors - "daylight", would be more conducive for productive work.

Ok, smarty but which one is right for me?

To put it quite simply. If you want to foster an ambience of warmth or cosy-ness, warm light is going to serve you better. This is ideal for lounges, dining rooms, bedrooms and sometimes bathrooms. Cool Light is more suited to environments where you are performing work - like your kitchen, garage and perhaps your bathroom. You'll notice that there is some overlap, that is because at the end of the day it's open to your opinion. This is your house we are talking about and you need to find what works for you.

Resources

Study on how light affects the perception of heat: https://onlinelibrary.wiley.com/doi/full/10.1111/ina.12500