Light Reflectance Values Calculator

Select the Door Facing, Lipping, Intumescent and/or Ironmongery species/finish from the drop-down lists below to show the Light Reflectance Values (LRV) and visual contrast readings. Examples of our standard facings as used in the calculator can be viewed in our product finish selector by Clicking here.

Door Facing  
Door Facing Type LRV
 
Finish  
00.0
Lipping  
Edge Detail LRV
 
Finish  
00.0
Frame  
Frame Type LRV
 
Finish  
00.0
Intumescent Colour  
Colour LRV
00.0
Ironmongery Finish  
Ironmongery Type LRV
 
Finish  
00.0
  • Lipping to Door Facing
    Lipping Finish
    Door Facing Finish
    LRV Difference
  • Door Facing to Frame
    Door Facing Finish
    Frame Finish
    LRV Difference
  • Lipping to Intumescent
    Lipping Finish
    Intumescent Colour
    LRV Difference
  • Door Facing to Ironmongery
    Door Facing Finish
    Ironmongery Finish
    LRV Difference

Please Note: This LRV Calculator is for approximate guidance only as exact finishes and environments can vary. If more detailed guidance is required, please contact our Technical Support Team on 01623 343111 or email sales@integrateddoorsets.com.

What are Light Reflectance Values?

Light Reflectance Value (LRV) is a universal value for ‘contrast’ which measures the total quantity of visible light reflected by a surface at all wavelengths and directions when illuminated by a light source. It represents a relative light and darkness value rather than an actual colour. Therefore, dissimilar colours could have the same LRV. Differences in LRV are used to assess the degree of visual contrast between surfaces such as door leaves and ironmongery in order to facilitate access into and through a building for the visually impaired.

Why do we need Contrast?

Visual contrast is the perception of a difference between one element of a building and another by reference to their LRV’s. Most registered blind people will still have some vision in colour. Only a small percentage (less than 5%) can see nothing at all, and even people within this group will generally have some sensitivity to light and shade. For people with good vision, differences in hue (the nature of the colour) or chroma (the intensity of the colour) provide adequate visual contrast. Unfortunately, this is not the case for all people who are blind or partially sighted. The main feature of a surface is the amount of light the surface reflects, or its Light Reflectance Value.

The LRV Scale

The LRV scale runs from 0, which is a perfectly absorbing surface that could be assumed to be totally black, up to 100, which is a perfectly reflective surface that could be considered to be the perfect white. Because of practical influences in any application, black is always greater than 0 and white never equals 100. The evidence based research available to date allows a degree of variability concerning the minimum LRV difference that is required to provide adequate visual contrast to people who are visually impaired.

Why are Light Reflectance Values Important?

The Equality Act 2010 requires that all new and refurbished public buildings and work places comply with current regulations via their ‘Access Statement’, ensuring safe entry, exit and safe passage throughout the building. As no detailed physical guidance is offered in the Act, specifiers following the guidance within the Building Regulations Approved Document M and BS 8300 would by default comply with the Equality Act. These regulations mean that people, regardless of disability, age or gender, must be able to gain equal access to public buildings. For visually impaired people this means, amongst other things, that there must be a good visual contrast between various elements of the building, including doorways, fixtures and fittings. As a result, the contrast between, for example, door leaf surface and ironmongery must achieve a certain level – as measured by LRV.

What Light   Reflectance Values are Required?

When specifying door facings and ironmongery, it is important to consider LRV differences and how they can be achieved to meet the requirements of BS8300 and Approved Document M. The definition of Visual Contrast in Building Regulations Approved Document M Volume 2 Para. 0.26 states that ‘the LRV between two surfaces should be greater than 30 points. Where illumination on a surface is greater than 200 lux, a difference in LRV should be a minimum of 20 points. Where door opening furniture projects beyond the face of the door or otherwise creates enhanced differentiation in shade a minimum LRV of 15 points is considered adequate.’

For more information, please refer to Building Regulations Approved Document M - Volume 2 and BS 8300-2:2018, Annex B and “Colour, Contrast & Perception, Design Guidance for Internal Built Environments” – Reading University.