How to calculate the amount of lighting needed for a space?

What are the parameters to consider? With Silumen , your lighting is successful.

The lighting needed is specific to each room and space. We tend to use lighting power (calculated in Watts) to define the illuminance of a room.

Today, let's talk about Lumens and not Watts. The LED allows a light output much higher than its congeners for a lower energy consumption.

Lumen is a unit of measurement of luminous flux indicating the total amount of light emitted by a luminaire. The power, expressed in Watts, indicates the amount of energy consumed, which turns out to be irrelevant to the efficiency of the LED.

On the energy level, the power to the number of Lumens becomes weaker and weaker. How to calculate the amount of lighting needed for a space? What are the parameters to consider? With Silumen , your lighting is successful.

Led suspendu blanc chaud

The correlation between "Lumens" and "Watts"

Calcul de la consommation électrique et le flux lumineux

Watts (W) = power consumption

This unit measures the electrical consumption or power used by the lighting device. The luminous efficiency of a light source was correlated with the electric power. Today, this unit of measurement only indicates the amount of energy used for the LED, which is low consumption.

Lumens (LM) = luminous flux

Lumens define the amount of light emitted by your light source. We are talking about its luminosity or luminous flux. The higher the number of lumens, the more your lighting system produces a significant light output and illuminates efficiently.

The same power consumption (calculated in Watts) does not necessarily produce the same brightness (calculated in Lumens).

When buying your luminaire from Silumen , think Lumens and not Watts!

In summary, Watts and Lumens: what's the difference?

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- The power of a light is not just about the energy consumed and the watts.

- The lumen is the parameter which directly measures the quantity of light emitted.

- LED bulbs are energy efficient and produce more light than compact halogen / fluorescent bulbs.

In LED, 1W is approximately equivalent to 100lm. Either way:

Luminous intensity approx. (in Lm) = Number of watts x 100

Power consumption (in W) = Number of lumens / 100

Another data: Lux (LX) = quantity of light per m2

This trick will allow you to quickly and easily calculate the light output of a lighting product.

This is data that is used to calculate the amount of light needed in a space. Lux measures the efficiency of lighting or illuminance.

Light flux received by an object or a surface (in lx) = Number of lumens / area in m2 to be illuminated ...

How many Lumens for my space?

Several factors must be considered in order to properly think out the layout and characteristics of your lighting equipment:

The type of room to be lit (shape, size, height of ceilings, etc.);

The type of luminaire used; The living spaces, those to enhance or highlight. The activity practiced. More subjective The desired atmosphere;

The furnishing style of the room (colors, furniture, etc.)

Below, some lighting tips:


Sought after atmosphere



Recommended color

Living room, dining room, bedrooms

Subdued, intimate atmosphere.


White hot

Living room, dining room, kitchen, bedrooms

Friendly atmosphere, moments of relaxation and rest.


White hot

Living room, dining room, kitchen, bedrooms.

General lighting of all types of rooms


Neutral White

Office, library, games room.

Atmosphere of work, games.


Neutral White

Activity areas (office, workshop) and passageways (corridors, entrance). Working atmosphere


Neutral White / Cool

Example A

Your room has an area of 15m2 to be fitted with two E27 LED 6W 220V G45 bulbs producing 600lm each for a consumption of 6W.

Calculate the brightness of your bulb per m2. Or, 600 lm / 15 m2 = 40 lumens / m2 or lux of illumination. Add the sum or multiply by the number of light points. Here we have two bulbs of the same type: 40 x 2 = 80 lux Refer to the table to get an idea of the mood of your room or space. We have a room conducive to relaxation and rest.

If you are looking for a more subdued atmosphere, you will simply have to opt for bulbs producing a lower light intensity, therefore less Lumens, to reduce the illumination.

By using the same light sources mentioned above in the example, 80 lumens per m2 for a living room of 25m2 will obviously be insufficient. The whole room cannot be lit.

So, how do you calculate the number of light sources needed to obtain satisfactory illumination?

Number of light points = Total recommended Lux / Lux produced by your luminaire

Example B

150 lux recommended for a living room / 40 lux produced by the LED bulb = 3.75 or 4.

To be even more specific, divide your space into different zones and determine the amount of Lux needed to create the desired mood in each zone. You will thus be able to illuminate each area or space according to your desires.

How do I know the number of lumens of Silumen products?

Let us always take the example ofE27 LED bulb 6W 220V.

The number of lumens is indicated in each product sheet.

How to get there? Expand the product sheet and click on "Technical sheet". Look for "Brightness (in lumens)".

Ampoule E27 6W fiche technique