How Many LED Lights Per Square Foot? Commercial Lighting Calculator
Calculate how many LED fixtures you need per square foot for warehouses, offices, retail, parking lots, and more. Includes foot-candle requirements by space type.
One of the most common questions contractors and facility managers ask: "How many LED lights do I need for my space?" The answer depends on the space type, ceiling height, desired light level, and fixture output.
Quick Reference: LED Fixtures Per Square Foot
| Space Type | Required FC | Ceiling Height | Fixture | Spacing | Coverage |
|---|---|---|---|---|---|
| Warehouse (general) | 30 FC | 20-30 ft | 150W UFO High Bay | 20x20 ft | 400 sq ft each |
| Warehouse (detailed) | 50 FC | 20-30 ft | 200W UFO High Bay | 15x15 ft | 225 sq ft each |
| Manufacturing | 50 FC | 15-25 ft | 200W High Bay | 16x16 ft | 256 sq ft each |
| Office | 40 FC | 9-10 ft | 50W 2x4 Troffer | 8x8 ft | 64 sq ft each |
| Retail | 50-75 FC | 10-14 ft | 50W Panel Light | 6x8 ft | 48 sq ft each |
| Parking lot | 2-5 FC | 20-30 ft pole | 150W Area Light | 60x60 ft | 3,600 sq ft each |
| Parking garage | 10 FC | 8-10 ft | 40W Vapor Tight | 20x20 ft | 400 sq ft each |
| School classroom | 40 FC | 9-10 ft | 40W 2x4 Troffer | 8x8 ft | 64 sq ft each |
| Gym/recreation | 50 FC | 20-30 ft | 240W High Bay | 20x20 ft | 400 sq ft each |
Step-by-Step Calculation
Formula
Number of fixtures = (Area × Required FC) ÷ (Lumens per fixture × CU × LLF)Where:
- Area = square footage of the space
- Required FC = foot-candles needed (see table above)
- Lumens per fixture = from product spec sheet
- CU = Coefficient of Utilization (typically 0.6-0.8)
- LLF = Light Loss Factor (typically 0.85 for LED)
Example: 20,000 sq ft Warehouse
- Required: 30 foot-candles
- Using: Auvolar UFO High Bay 150W (22,500 lumens)
- CU: 0.7 (typical for warehouse)
- LLF: 0.85
At wholesale pricing, total fixture cost is significantly below retail. With DLC rebates of $50/fixture, net cost drops further. Contact us for exact project pricing.
Example: 50,000 sq ft Parking Lot
- Required: 3 foot-candles (average)
- Using: Auvolar OT Series 150W Area Light (22,000 lumens)
- CU: 0.45 (outdoor, wider distribution)
- LLF: 0.85
IES Foot-Candle Requirements by Space Type
These are recommended levels from the Illuminating Engineering Society (IES):
Industrial
- Warehouse (general storage): 20-30 FC
- Warehouse (detailed tasks): 50 FC
- Manufacturing (rough work): 30 FC
- Manufacturing (fine work): 50-100 FC
- Loading docks: 20-30 FC
- Cold storage: 20-30 FC
Commercial
- Office (general): 30-50 FC
- Office (task lighting): 50-75 FC
- Retail (general): 50 FC
- Retail (merchandise): 75-100 FC
- Restaurant (dining): 10-20 FC
- Restaurant (kitchen): 50-75 FC
Institutional
- Classroom: 40-50 FC
- Library: 50 FC
- Hospital (general): 30 FC
- Hospital (examination): 75-100 FC
- Church: 20-30 FC (worship), 50 FC (reading)
Outdoor
- Parking lot: 1-5 FC
- Parking garage: 5-10 FC
- Walkway: 1-2 FC
- Building entrance: 5-10 FC
- Sports field: 30-100 FC
Free Lighting Design from Auvolar
Don't want to calculate manually? Auvolar offers free photometric lighting design for any project. Send us your floor plan and we'll create a professional layout with:
- Exact fixture count and placement
- Foot-candle calculations on a grid
- Uniformity ratios
- Energy code compliance verification
- 3D visualization
Contact: sales@auvolar.com or (626) 364-9198 or use our online tool at auvolar.com/tools/photometric-request.
Need Help With Your Lighting Project?
Auvolar provides free lighting design, photometric layouts, and rebate assistance for commercial projects.
Auvolar Engineering Team
City of Industry, California
Our engineering team has 15+ years of combined experience in commercial LED lighting design, photometric analysis, and energy-efficient building systems. We hold DLC QPL listing expertise and work directly with California utilities on rebate qualification. All technical content is reviewed by licensed electrical engineers.