LRV, definition and purpose

2020, November

LRV is the acronym for Light Reflectance Value.  This coefficient is the total quantity of light, visible and usable, reflected in all directions and wavelengths by a surface, when illuminated.


How does it work? 

LRV runs on a scale of 0 to 100%, zero being absolute black and 100 being perfectly reflective white. These two extremes are purely theoretical because the darkest black usually reaches the value of 5% and the most immaculate white reaches 85%. Some yellows can also reach 80-90%.

Below the mid-point of 50%, the colour will tend to absorb more light than it reflects in the room. On the contrary, a colour with a LRV higher than 50% reflects more light than it absorbs. In short, the higher the value, the lighter the color.

Careful with yellow!
LRV can be misleading when it comes to yellow. Yellow is one of the most reflective hues in the spectrum. In addition, the more area it covers the more intense it grows exponentially. People err when choosing yellow more than any other color. They end up with a too vivid lemon yellow that borders on needing eye protection to enter the room when they really were going for a softer, buttercream color. For this colour, it is better to consider the coefficient of visual intensity (how bright or dull the colour is) rather than LRV.
In practice
EN 12464-1 standard specifies the following range for the main walls:

                                                          LRV1

In practice the following default values are recommended:
                                                          LRV2

What is the purpose of LRV?
A first use concerns colours planning, depending on the type of use of the interior space. For example, in workplaces, careful configuration for proper visual ergonomics is paramount.

Another main purpose relates to energy savings. The building’s environmental standards that are currently in force, such as HQE label for example, integrate light reflection factors into their referential. In the specifications of some projects, the required LRV must exceed 20%, in order to minimize lighting electricity consumption.


TecSOM’s brightly coloured carpets offer very high LRV, they reflect light well and promote energy savings. All the collections are made with solution dyed yarns, providing high colours fastness, even for the lightest shades which are more fragile, and guaranteing the beauty of the product over long years.


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