Installing too few high bay lights leads to dark, unsafe working conditions and failed code inspections, while installing too many wastes money on unnecessary fixtures and higher electricity bills. Use this simple calculation to get the right number of lights for your warehouse:

1. Key Inputs You Need:

   • Total square footage of your space (length x width)

   • Ceiling height (mounting height for high bays)

   • Required illuminance level (foot-candles): 30 FC for general storage, 50 FC for order picking areas, 75 FC for detailed assembly work

   • Fixture lumen output (listed on every product spec sheet)

   • Coefficient of Utilization (CU): typically 0.6-0.8 for warehouses with light-colored ceilings and walls, 0.4-0.6 for dark warehouses

   • Light Loss Factor (LLF): typically 0.8 for LED fixtures to account for lumen depreciation and dust buildup

2. The Calculation Formula:
   Number of fixtures = (Total Square Footage x Required Foot Candles) / (Fixture Lumens x CU x LLF)

3. Example Calculation:
   For a 100ft x 100ft (10,000 sqft) warehouse with 20ft ceilings, requiring 50 FC for order picking, using 150W LED high bays with 22,500 lumens, CU=0.7, LLF=0.8:
   Number of fixtures = (10,000 x 50) / (22,500 x 0.7 x 0.8) = 500,000 / 12,600 = ~40 fixtures

4. Layout Tip: Space high bay lights evenly in a grid pattern, with spacing between fixtures equal to 1.5x the mounting height for uniform light distribution. For the most accurate results, request a free DIALux layout from our team.