Garage Lighting Lumens & Fixture Count Calculator
Plan bright, efficient garage lighting. Enter room size and choose a target illuminance. The tool estimates total lumens required, recommends a fixture count and a row × column layout, and projects power use & cost. Metric & imperial supported.
How to use
- Choose units (Metric or Imperial).
- Enter length × width × height of your garage.
- Select a lighting level (storage → workshop) or enter a custom value.
- Set your fixture lumens and wattage (typical 4‑ft LED: 4,000–6,000 lm, 30–50 W).
- Click Calculate to see lumens needed, fixture count, a suggested layout, spacing and energy cost.
Worked example
Single garage 6.0 m × 3.0 m × 2.4 m, General level (250 lux), walls Medium reflectance, fixture 5,000 lm / 40 W, LLF 0.85, usage 15 h/week, price $0.30/kWh.
- Lumens needed: 6×3×250 × 1.00 ≈ 4,500 lm → with LLF 0.85 → 5,295 lm from fixtures
- Fixture count: 5,295 ÷ 5,000 ≈ 2 fixtures
- Layout: 1 × 2 grid → spacing ≈ 6.0 m along length, 3.0 m across (centered)
- Power: 2 × 40 W = 80 W → 15 h/week = 1.2 kWh/week → ~$0.36/week
Garage lighting calculator
FAQs
How bright should a garage be?
Storage areas are fine around 150 lux (≈15 fc). For general use, 250 lux; for bench work, 500 lux or more. Detailing/fine tasks can use 750 lux+.
What is LLF / maintenance factor?
It accounts for lumen depreciation and dirt over time. A value of 0.80–0.90 is common for LEDs; the calculator divides by LLF so fixtures provide enough initial lumens.
How do you choose the grid?
The tool picks rows × columns to roughly match room proportions and then shows spacing. Keep spacing near 1.0–1.5× the mounting height for uniform light.
Which CCT/CRI is best in a garage?
4000–5000 K (neutral‑cool) and CRI 90+ give crisp contrast for tools and paint/auto work.