LUMENS AND LUXES: WHAT ARE THEY AND WHY YOU MUST KNOW HOW TO CALCULATE THEM
One of the most common mistakes made in the world of interior design is to conceive lighting as a superfluous need or as an futile expense.
The truth is that when a space is conceived, both natural and artificial light have a sense, a practice and necessary argument: SEE AND FEEL the space.
To be able to see and feel a space it’s necessary that the projected light is present in our project, the light has to be analyzed in order to generate the wanted effects and COMPLETE the architectural design.
If we understand that lighting is fundamental in our design we will understand then that light is not a luxury but a need for VALUE that will not only give more to our project but to the people who will inhabit it.
LUMENS AND LUXES: WHAT ARE THEY?
More than 15 years ago, when the LED (Light Emitting Diode) became more efficient in terms of light emission, the terms LUMENS and LUXES began to become popular and with it also came confusion.
When buying light emitters, luminaires, lamps or any luminous body, it is necessary to understand these 2 concepts:
Let’s look at each one individually:
1- LUMENS: AMOUNT OF LIGHT EMITTED BY EQUIPMENT
Lumens refer to the amount of light emission in a piece of equipment.
Lumens is a unit of measurement (just as meters, liters, inches, ounces, etc.) and refers exclusively to the amount of light that EMITS certain luminous body.
Its acronym is “lm” and technically it is called “luminous flux”.
Lumens never refer to the amount of light a space needs. There is a lot of wrong information on the internet that confuses lumens with luxes
2- LUXES: AMOUNT OF LIGHT NEEDED (THAT CAN BE MEASURED) IN A SPACE.
Luxes, on the other hand, does concerned to the amount of light at an specific point in space.
It is the unit of measurement obtained by measuring the luminous flux at an specific position with a device called LUXMETER
WHY LUXES SHOULD BE MEASURED IN A SPECIFIC POSITION?
On the Internet there are tables of “recommendations” for the luxes requirement in generic space (i.e a bedroom, a dinner), but very few or almost none of them indicates from which specific position of the space to measure.
The luxes amount measured at ground level are very different from the luxes that can be measured at the height of a table in the same space.
So, this means that recommendations coming from a generic table of luxes it’s in reality just a unreliable abstraction.
Let’s get this practical: in a Grocery Store, Luxes measured close to the products must always be bigger than Luxes in the aisle.
This is why we consider that those generic luxes numbers recommended on many websites are very subjective. Basically they’re not very reliable when you want to make a professional lighting design.
Remember that “over sizing” the light and then dimming it with a regulator is not a solution either. Here we explain the reasons why the LED dimmer is not the best of the options.
As a conclusion we must understand that lighting design is not just knowing about the amount of light a space needs, just as designing a space is not just knowing the measurements of it.
Understanding what Lumens and Luxes means as units of measurement that serve to quantify light is a big step for this moment in the history of enlightenment. In other posts we will be explaining to you professional and successful ways to calculate luxes and lumens needed for a space.
If you need a team of lighting designers for your project remember that LUMSTOCK architects are here to help you: