Question 1

How many lumens do I need per room?

Accepted Answer

Multiply room sq ft × foot-candles needed. Living room: 10-20 fc → 100-200 sq ft room needs 1000-4000 lumens. Kitchen: 30-50 fc. Bedroom: 10-20 fc. Bathroom: 50-70 fc.

Question 2

What is the difference between ambient, task, and accent lighting?

Accepted Answer

Ambient: general room illumination. Task: focused work lighting (desk lamp). Accent: decorative highlighting (art lights). Good design layers all three types.

Question 3

What's the difference between lumens and lux?

Accepted Answer

Lumens measure total light output from a source. Lux measures light arriving at a surface. Same lumens in a smaller area = higher lux.

Question 4

How do I convert old wattage to lumens?

Accepted Answer

Roughly: 40W incandescent ≈ 450 lumens, 60W ≈ 800 lumens, 100W ≈ 1600 lumens. LED equivalents use 80-90% less power for same lumens.

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