KelvinPlanHow much light each room needs, and what colour it should be.

Lighting a 8 × 18 ft home office

Total light needed
6,480lumens
144 ft² × 45 foot-candles
Room area144ft²
Target light levelIES guidance for a home office45foot-candles
Total lumens6,480lm
Colour temperatureneutral white keeps alertness up4000K
Bulbs (800 lm each)9bulbs
Recessed cans (4 ft spacing)720 lm each9fixtures
Room
home office
Width
8 ft
Length
18 ft

Where 6,480 lumens comes from

Lighting is specified in foot-candles — lumens landing on each square foot of the surface you care about. A home office is worked to 45 foot-candles. Across 144 ft² that is 6,480 lumens in total.

Split it up

One fixture putting out 6,480 lumens and 9 fixtures adding up to the same number light a room very differently. A single source throws hard shadows and glare; several spread the light and make the room feel larger. Aim for layers — ambient, task, and something low for the evening.

Colour temperature

4000K suits this room. Warmer light reads as relaxed and is what you want where people wind down; cooler light keeps edges and colours crisp, which matters where there is work to do.

Notes

  • Foot-candles are lumens per square foot at the work surface. Ceilings above 9 ft, dark walls or dark flooring all eat light — add roughly 10% per extra foot of ceiling height.
  • Spread the total across several fixtures rather than one bright source. One 6,480 lm fixture and 9 smaller ones add up the same but look completely different.

Nearby sizes