Number of Lights Calculator

Number of Lights Formula:

\[ \text{Number of Lights} = \frac{FC \times Area}{Lumens\_per\_light} \]

Number of Lights:

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is a Number of Lights Calculator?

Definition: This calculator estimates the number of light fixtures needed to achieve a desired illumination level in a given space.

Purpose: It helps architects, interior designers, and lighting professionals determine the appropriate number of lights for optimal illumination.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ \text{Number of Lights} = \frac{FC \times Area}{Lumens\_per\_light} \]

Where:

\( FC \) — Desired illumination level (foot-candles)
\( Area \) — Area to be illuminated (square feet)
\( Lumens\_per\_light \) — Light output of each fixture (lumens)

Explanation: The total required lumens (FC × Area) is divided by the lumens provided by each light fixture.

3. Importance of Proper Lighting Calculation

Details: Accurate lighting calculations ensure adequate illumination for tasks, energy efficiency, and visual comfort in spaces.

4. Using the Calculator

Tips: Enter the desired illumination level in foot-candles (common values: 30-50 for offices, 10-20 for hallways), area in square feet, and lumens per light (default 800 lm/light).

5. Frequently Asked Questions (FAQ)

Q1: What is a foot-candle (FC)?
A: A foot-candle is a unit of illuminance equal to one lumen per square foot.

Q2: How do I determine the required FC level?
A: Refer to lighting standards (e.g., IES recommendations) based on space type and activities.

Q3: Why does the result show whole numbers?
A: The calculator rounds up since you can't install a fraction of a light fixture.

Q4: Does this account for light loss factors?
A: No, consider multiplying the result by 1.2-1.5 to account for light loss due to aging, dirt, etc.

Q5: What's a typical lumens value for LED bulbs?
A: Common values: 800-1600 lumens for residential bulbs, 3000-5000+ for commercial fixtures.