What is Reflection Factor?
Gharpedia.com helps to Build/Own/Rent/Buy/Sell/Repair/Maintain your dream house by providing all the tips & tricks in easy languages. It provides solutions to all problems pertaining to houses right from concept to completion.
Different objects reflect the light in different ways. For example, diffuse surfaces appear the same when viewed from different directions, whereas a mirror looks very different from different points of view!
Must Read: Aims of Good Lighting in a House
Courtesy - 123rf
Reflection factor is a ratio of luminous flux reflected by a body (with or without diffusion) to the flux it receives .i.e.
Reflection factor = luminous flux reflected by a body / luminous flux received by the body
The ratio of the total amount of radiation, as of light, reflected by a surface to the total amount of radiation incident on the surface.
In other words, it is the fraction of radiant energy that is reflected from a surface.
Some symbols used for reflection factor are:
rc= Reflection factor of ceiling.
rw = Reflection factor of parts of the wall between the working surface and the luminaires.
rf= Reflection factor of floor.
Light reflecting factors of commonly used materials:
|Aluminum, pure, highly polished||80 – 87|
|Aluminum, anodised, matt||80 – 85|
|Aluminum, polished||65 – 75|
|Aluminum, matt||55 – 75|
|Aluminum coatings, matt||55 – 56|
|Chrome, polished||60 – 70|
|Vitreous Enamel, white||65 – 75|
|Lacquer, pure white||80 – 85|
|Copper, highly polished||70 – 75|
|Nickel, highly polished||50 – 60|
|Paper, white||70 – 80|
|Silvered mirror, behind glass||80 – 88|
|Silver, highly polished||90 – 92|
|Oak, light polished||25 – 35|
|Granite||20 – 25|
|Limestone||35 – 55|
|Marble, polished||30 – 70|
|Plaster, light||40 – 45|
|Plaster, dark||15 – 25|
|Sandstone||20 – 40|
|Plywood, rough||25 – 40|
|Concrete, rough||20 – 30|
|Brick, red||10 – 15|
|Paint, white||75 – 85|
|Paint, medium grey||25 – 35|
|Paint, dark blue||15 – 20|
|Paint, light green||45 – 55|
|Paint, dark green||15 – 20|
|Paint, light yellow||60 – 70|
|Paint, brown||20 – 30|
|Paint, dark red||15 – 20|