Simple Calculation of Flood Light, Facade Light, Street Light & Signage Light-(Part1)


  • Outdoor Lighting can be classified according to the location where it can be installed or its function which use for highlight landscape area.
  • Outdoor Lighting can be classified as
  1. Flood Lighting,
  2. Facade Lighting and
  3. Signage Lighting
  4. Street Light

(A) General Outdoor Flood Lighting:

  • Normally Pole mounted floodlights are used to illuminate general lighting area of parking lots and storage yards. 
  • There are three factor should be consider while designing of outdoor flood lighting.
  1. Mounting Height.
  2. Spacing
  3. Aiming Distance.
  4. Horizontal Aiming.

1) Mounting Height:

  • Mounting height should be one half the distance across the area to be lighted.
  • If the area to be lighted is 16 Meter, the lowest recommended mounting height is 8 Meter. 
  • Mounting height = 1/2 distance to be lighted
  • 1/2 (16 Meter.) = 8 Meter. 


2) Spacing:

  • When more than one Luminar / pole is required than distance between two adjacent luminar / Pole is 4 times Mounting height of luminar /pole.
  • If the mounting height of luminar /Pole is 8 Meter than distance between adjacent Luminar is 32 Meter.
  • Pole Spacing = 4 x mounting height.
  • 4 (8 Meter pole) = 32 Meter between poles


3) Vertical Aiming:

  • The fixture should be aimed 2/3 of the distance across the area to be lighted and at least 30 degrees below horizontal. 
  • If the area to be lighted is 16 Meter across, the recommended aiming point is 10.6 Meter.
  • Aiming point = 2/3 Distance to be lighted.
  • 2/3 (16 Meter) = 10.6 Meter aiming point
  • To minimize glare, the recommended aiming point distance should never exceed twice the mounting height.
  • If a pole is 8 Meter high, the vertical aiming point should not exceed 16 Meter.  
  • 2 (8 Meter mounting height) = 16 Meter. 


4) Horizontal Aiming:

  • When two floodlights is mounted to a single pole then horizontal aiming also must be considered.
  • Each floodlight should be vertically aimed according to the two-thirds rule. 
  • The floodlights should be aimed up to 90 degrees apart. 


About Jignesh.Parmar
Jignesh Parmar has completed M.Tech (Power System Control), B.E(Electrical). He is member of Institution of Engineers (MIE) and CEng,India. Membership No:M-1473586.He has more than 16 years experience in Transmission -Distribution-Electrical Energy theft detection-Electrical Maintenance-Electrical Projects (Planning-Designing-Technical Review-coordination -Execution). He is Presently associate with one of the leading business group as a Deputy Manager at Ahmedabad,India. He has published numbers of Technical Articles in “Electrical Mirror”, “Electrical India”, “Lighting India”,”Smart Energy”, “Industrial Electrix”(Australian Power Publications) Magazines. He is Freelancer Programmer of Advance Excel and design useful Excel base Electrical Programs as per IS, NEC, IEC,IEEE codes. He is Technical Blogger and Familiar with English, Hindi, Gujarati, French languages. He wants to Share his experience & Knowledge and help technical enthusiasts to find suitable solutions and updating themselves on various Engineering Topics.

8 Responses to Simple Calculation of Flood Light, Facade Light, Street Light & Signage Light-(Part1)

  1. KVM says:

    very informative

  2. Mohamed Akram Khan says:

    Thank you, Eng Parmar. Before we consider the distances mentioned in your post, surely we need to consider the required LUX and the lumens of the luminaries.
    Please let me have your response to this question.
    Kind regards
    M. Akram Khan

  3. gk says:

    Great ideas for deciding the required parameters. Well explained !

  4. Imelda Alumbro says:

    Thank you sir.

  5. p manikandan says:

    super very usefull

  6. Master Electrician IT says:

    Dear Sir,

    Do you have a calculation for making distribution box / electrical Panel entrance of building and warehouses, could you please quote us. I plan to put up a small electrical service. I need complete data and illustration.

    Thank you
    Khalid Morales

  7. Khurshid Hafiz says:

    Good and simple way of explaining. We need to consider the LUX of the luminaries as well as the relevant standards.

  8. Thank you for sharing useful information it helps in manual calculation but now these days alots of tools and software support in calculating.

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