Lighting Calculator

Calculate optimal lighting requirements for any room based on size, function, and light type to ensure proper illumination levels and energy efficiency.

How Lighting Calculator Works

Lighting Requirements by Room Type

Room Type	Foot-Candles	Purpose
Kitchen/Workshop	50 FC	Bright task lighting for detailed work
Office/Study	40 FC	Bright work lighting for reading/writing
Bathroom/Dining/Laundry	30 FC	Bright, even lighting for grooming/tasks
Living Room	25 FC	Comfortable ambient lighting
General/Basement	20 FC	Standard general lighting
Bedroom/Closet	15 FC	Soft, relaxing lighting
Garage/Hallway	10 FC	Basic illumination for safety

Light Type Efficiency Comparison

Light Type	Lumens/Watt	Lifespan	Best For
LED	100	25,000 hrs	Most efficient, all applications
Fluorescent	70	10,000 hrs	Large areas, offices, garages
CFL	60	8,000 hrs	General lighting, retrofit
Halogen	25	2,000 hrs	Accent lighting, spotlights
Incandescent	15	1,000 hrs	Least efficient, warm ambiance

Calculation Formulas

Total Lumens Required:

Room Area (sq ft) x Required Foot-Candles

Total Watts Needed:

Total Lumens / Lumens per Watt (efficiency)

Number of Fixtures:

Total Lumens / Lumens per Fixture

Annual Energy Cost:

(Watts / 1000) x Hours/Day x 365 x Rate per kWh

Lighting Design Tips

Layer your lighting: Use ambient, task, and accent lighting together
Choose LED bulbs: Most energy-efficient with longest lifespan
Install dimmer switches: Provides flexibility and energy savings
Consider color temperature: 2700K warm, 3000K neutral, 4000K+ cool
Use natural light: Position workspaces near windows when possible
Avoid glare: Use diffused lighting and proper fixture placement
Plan for tasks: Provide extra lighting for reading, cooking, working

Cite this page as:

Daniel, P. Lighting Calculator. Available at: https://constructioncalculators.com/lighting-calculator/. Accessed: October 25, 2026.