1. What is an LED Light Requirement Calculator?

Definition: This calculator determines the total lumens needed for LED lighting based on desired illuminance (in foot-candles) and the area to be illuminated.

Purpose: It helps lighting designers, architects, and homeowners properly size LED lighting installations for optimal illumination.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• Lumens — Total light output required (lm)
• FC — Desired illuminance level (foot-candles)
• Area — Size of the area to be illuminated (square feet)

Explanation: The desired illuminance level is multiplied by the area size to determine the total lumens needed from the light source(s).

3. Importance of Proper Lighting Calculation

Details: Accurate lumen calculation ensures adequate lighting for tasks, energy efficiency, and visual comfort while avoiding over-lighting and wasted energy.

4. Using the Calculator

Tips: Enter the desired illuminance in foot-candles (typical values: 10-20 for general lighting, 30-50 for task lighting) and the area in square feet. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What are typical foot-candle requirements?
A: Residential: 10-20 fc; Office: 30-50 fc; Retail: 50-75 fc; Detailed work: 75-100 fc.

Q2: How does this differ for LED vs traditional lighting?
A: The calculation is the same, but LEDs typically produce more lumens per watt, making them more energy-efficient.

Q3: Should I account for light loss factors?
A: Yes, consider adding 20-30% to the calculated lumens to account for fixture efficiency, room reflectance, and light depreciation over time.

Q4: How do I convert lux to foot-candles?
A: 1 foot-candle = 10.764 lux. For lux-based calculations, divide by 10.764 before using this calculator.

Q5: Does this account for multiple light fixtures?
A: No, divide the total lumens by the output of individual fixtures to determine how many fixtures you need.