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What is LRV? What is Light Reflectance Value?
Understanding LRV is crucial when choosing color for the built environment, interior and exterior.Lori Sawaya, Color Strategist Albert R. Sawaya II, EE, MBA • Metrology Expert
©2005 all rights reserved
LRV - You may have noticed these three letters on manufacturer’s color specifications, on the back of paint swatches or noticed an entire column dedicated on precious few square inches of space available in the index of paint fandecks. What do those letters stand for? What does the LRV number mean and how is it used? It is rather simple. Paying attention to a color’s LRV can prevent poor color/paint color selections by helping you determine and evaluate certain color characteristics.
Keywords: LRV, Light Reflectance Value, brightness, lightness, visual ergonomics
LRV is the acronym for Light Reflectance Value. As mentioned, LRV is on the back of most color swatches and in the index of all major brands’ fandecks. Value is often confused with the term intensity. Intensity is about vividness or dullness – is the color clear or muted. Value is an important term used in color and it speaks strictly to the lightness or darkness of a color.
What is LRV Light Reflectance Value?
Light Reflectance Value (LRV) is the total quantity of visible and useable light reflected by a surface in all directions and at all wavelengths when illuminated by a light source. (ref. British Standard BS 8300:2001/A1:2005)
LRV is a measurement that tells you how much light a color reflects, and conversely how much it absorbs. LRV runs on a scale from 0% to 100%. Zero assumed to be an absolute black and 100% being an assumed perfectly reflective white. An absolute black or perfectly reflecting white does not exist in our everyday terms. Approximately speaking, the average blackest black has a LRV of 5% and the whitest white 85%. Some yellows can measure up into the 80′s or 90′s as well.
How do color pros use LRV Light Reflectance Value?
Color consultants, architects, and designers use LRV data in several stages of color planning. Many examples can be found in the workplace. Careful planning for proper visual ergonomics is paramount in color design. From individual work surfaces to the outside walkways, ramps, hand-railings and everything in between. From a sustainability point of view, a wall color with a higher LRV supports lighting plans by helping to propagate daylight deep into the space. Thereby reducing the standard number of lighting fixtures required to enable employees to efficiently and safely perform their tasks.
How can homeowners use LRV Light Reflectance Value to choose paint colors?
Most important for the do-it-yourselfer is to refer to color specifications for exterior products. For example, vinyl siding. Painting vinyl siding with a color that has too low of an LRV, that absorbs too much light and energy and thus retains too much heat, could result in warped siding. Some paint manufacturers have developed special formulations for painting heat-sensitive exterior surfaces. They offer diverse color choices. However, if you do not use one of those specially formulated products, you are limited to a paint color that is within the same LRV range as the original color. Else you risk warping and voiding any warranties.
Interior Color: LRV provides a reference as to how light or dark a color could look and feel once up on all the walls. Remember LRV runs on a scale of 0% to 100%, 50% would be a mid-value paint color. Fifty percent LRV is the common guideline for residential interiors.
Below the mid-point of 50%, and you know the color will tend to be darker absorbing more light than it will reflect back into the room. Thus, an interior lighting plan that accounts for the darker paint color should be a priority.
Colors with LRV higher than 50% will be lighter and will reflect more light back into the room than is absorbed.
When sampling paint colors, paying attention to Light Reflectance Values as you try different hues, tints, tones and shades creates benchmarks that can assist you in arriving at color selections quickly and efficiently.
What are the precautions?
It is true that LRV Light Reflectance Value communicates a lot about a potential wall color, possibly provides even more of a sense of the color than those very small color chips – and we all know the issues with relying on just the small color chips.
LRV refers to the percentage of light reflected by the paint color regardless of how much light is present. The LRV number is a measurement, a piece of data and is one of the few things about a color that is a consistent factor. No matter from what direction the natural light enters a room, no matter what reflection of color you get from the other elements in the room, no matter what other conditions exist that will affect the context in which the wall color is experienced, the LRV is the LRV. However. . .
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 it grows more intense exponentially. People err when choosing yellow more than any other color. They end up with a too bright Lemon Chiffon yellow that borders on needing eye protection to enter the room when they really were going for a softer, more muted Buttercream color.
There is a difference between Light Reflectance Value and visual brightness albeit subtle. When choosing yellow wall colors, consideration of visual intensity – how bright or dull the color LOOKS – would be a more prominent consideration than the LRV Light Reflectance Value number.
LRV is a guideline. A relative point of reference for predicting how light or dark a color will look and feel once up on the walls. It is not a set standard by which to choose colors. Rather an indicator to help you make your best guess. And choosing wall colors is all about guessing.
No one can predict how a color will feel once it is out of the can and on structure. No matter who it is, designer, professional color designer, architect, or your next-door neighbor… they guess. The difference is some people are better guessers than others. What makes some people better paint color guessers than others is a matter of knowledge, taste, and experience.
With your new knowledge and clearer understanding of LRV Light Reflectance Value, you are one-step closer to expertly choosing paint colors that are pleasing and appropriate for the inherent lighting and chosen design style of interior spaces and best suited to exterior applications.
©2005 Lori Sawaya – LRV Light Reflectance Value All rights Reserved