Lighting calculations Excel sheet

Lighting Calculations Excel sheet : Free excel sheet for illumination and lighting Calculations for building This spreadsheet calculates the required illumination for eatch room in a building.

Lighting Calculations
 Lighting Calculations Excel sheet 

 Lighting calculations Excel sheet


Factors affected on illuminance calculations:

1-Room Reflectance

The room is consldered to consist of three main surfaces:

  • The ceiling caity.
  • The walls,and 
  • The floor cavity ( or the horizontal working plane ).
The effective reflectances of the above three surfaces affect the quantity of reflected light received by the working plane.

2-Luminaire maintenance factor (LMF)

Is the proportion of the initial light output from a luminaire after a set time to the initial light output from a lamp after a set time .

Three factors must be considered in its determination:

  • the type of luminaire
  • atmospheric conditions, and
  • maintenance interval.

3- Room surface maintenance factor ( RSMF )

is the proportion of the illuminance provided by a lighting installation in a room after a set time compared with that occurred when the room was clean

4- Utilization factor ( UF )

Is the proportion of the luminous flux emitted by the lamps which reaches the working plane.

Factors that affect the value of UF are as follows:

  • Light output ratio of Luminaire 
  • Flux distribution of Luminaire
  • Room proportions
  • Room Rflectance
  • Spacing/Mounting height ratio