Buying lighting should be simple. Find a light you like, buy it and get it installed it. But as technology has evolved and people’s preferences have changed, the number of options on the market has grown exponentially. There’s not only a huge range of lights available, but within each light you have choices to make. One of these, and perhaps the most confusing of all, is how many lumens should my light bulb be?
We’ve all struggled at one time or another in a room that was just too dim to see what we were doing properly. Whether reading in the living room or chopping veg in the kitchen, the right amount of light is critical to the task, and this is where lumens come in.
What are lumens?
Put simply, this is how bright the light is.
Lumens are a measure of how much visible light is emitted by the bulb and are based on how humans see light. They’re a standard global unit so, regardless of the manufacturer or country, a 500-lumen light bulb will always give out the same brightness of light.
The number of lumens is what you should consider to ensure comfortable and practical levels of light.
What is lux?
One lux equals one lumen per square meter.
Lux is very useful for working out the level of lighting for a room, because it is tied to area measurements. You can think of it as the intensity of light within an area. For example, an office would need to have a higher lux value (greater illuminance) than a living room.
Where do watts come in?
Watts are the amount of power consumed by the light bulb, and don’t actually have anything to do with the brightness of the light that comes out. There used to be a correlation between the two, more watts, more lumens, but this isn’t the case now as technology has evolved. Different types of bulbs have different lumen-per-watt ratios, which is why LED lights can use so much less energy while producing the same amount of light.
How bright should my room be?
As you might expect, different rooms in your house will need different levels of lighting, based on their purpose. The brightness of each space does come down to personal preference, but almost all preferences fall within a given range.
To get the right level of brightness - comfortable, practical and stylish - you need to consider lux and work out your lumens from there. We’ve summarised how many lux you should have for each room of the house:
|
Space |
Lux |
Lumens example calculation |
|
Indoor |
||
|
Hallway |
100 - 300 |
200 lux * 16 m2 = 3200 lumens |
|
Living room |
100 - 300* *If you spend a lot of time reading in your living room, we recomend between 300 and 500 lux would be best |
200 lux * 16 m2 = 3200 lumens |
|
Bedroom |
100 - 300 |
200 lux * 16 m2 = 3200 lumens |
|
Dining room |
500-700 |
600 lux * 16 m2 = 9600 lumens |
|
Kitchen (general) |
300 - 500 |
400 lux * 16 m2 = 6400 lumens |
|
Kitchen (task) For over work surfaces, cookers etc |
500 - 800 |
750 lux * 16 m2 = 12000 lumens |
|
Bathroom (general) |
300 - 500 |
400 lux * 16 m2 = 6400 lumens |
|
Bathroom (task) By mirrors and wash basins |
500 - 700 |
750 lux * 16 m2 = 12000 lumens |
|
Home office |
500 - 800 |
750 lux * 16 m2 = 12000 lumens |
|
Outdoor |
||
|
Driveway & parking |
100 - 200 |
150 lux * 16 m2 = 2400 lumens |
|
Garden lighting |
50 - 200 |
125 lux * 16 m2 = 2000 lumens |
|
Patios & decks |
100 - 200 |
150 lux * 16 m2 = 2400 lumens |
|
Security lighting |
300 - 500 |
400 lux * 16 m2 = 6400 lumens |
|
Workshop |
800 - 1100 |
900 lux * 16 m2 = 14400 lumens |
How many lumens do I need?
In the chart above we’ve included the number of lumens per room for a 4 x 4 metre room. To work this out for your own room size:
lux * room size (in square metres) = lumens
For our 4 x 4m bedroom, that would be:
200 lux * 16 m2 = 3200 lumens
From here, you can work out the number of light (bulbs) that you need by adding up their collective lumens.
In this example, you could have:
- 4 x 800 lumen downlights
- 2 x 1000 lumen pendant lights and 2 x 600 lumen wall lights
The number of lumens should be a guide, and we would always recommend going a little higher if you’re on the fence between higher and lower.
Lumens & efficiency
You may see efficiency mentioned in a light bulb description. This also uses lumens, and is your lumen-per-watt ratios. The higher the number, the more efficient the light is.
LEDs have a very high lumen to watt ration, much greater than old style incandescent bulbs. LED lights can use much less energy while producing the same amount of light.
Dimmers
If you would like some extra flexibility, light bulbs that can be dimmed are a great way to ensure that you have the level of light that you desire and need for all occasions. A dimmer switch can take a room from a focused workspace to a relaxed ambience with the twist or flick of a switch. In the age of home working this has become increasingly popular.
Dimmers reduce the number of lumens output and therefore the brightness of the room. Not all light bulbs are dimmable so ensure that you select a dimmable globe if you are wanting to install a dimmer switch.
Ready to brighten your World?
We hope our guide has helped you demystify these lighting terms and work out how many lumens you might need for that new lightbulb. Light bulbs come in a huge range of brightness, everything from 20 to 8000+. Discover our vast selection of light bulbs online- no matter what shape, size, style, colour, or luminosity you’re looking for, we’re confident we’ll have it.
Contact our friendly team if you have any specific questions or need help finding anything in particular.
