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

Recessed lights for a 26 × 26 ft bedroom with a 9 ft ceiling

Recessed lights needed
36lights
6 × 6 grid, about 4.3 ft apart in a 26 × 26 ft bedroom
Layoutacross the 26 ft dimension × along the 26 ft dimension6 × 6
Spacing (rule of thumb)half of the 9 ft ceiling4.5ft
Actual spacing to mark outafter rounding to whole fixtures4.3 × 4.3ft
First light from the wallhalf a spacing — closer washes the wall, further leaves dark corners2.2 × 2.2ft
Room area676ft²
Target light levellow ambient; reading needs its own lamp15fc
Total lumens needed10,140lm
Lumens per fixtureabout 4 W each in LED282lm
Room width
26 ft
Room length
26 ft
Ceiling height
9 ft
Room
bedroom

The grid

Spacing for recessed cans is ceiling height divided by two. A 9 ft ceiling gives 4.5 ft, which across a 26 × 26 ft room works out to a 6 × 6 grid — 36 lights.

Rounding to whole fixtures moves the real spacing to 4.3 × 4.3 ft. Mark the ceiling off those numbers, not off the rule of thumb. The first row sits 2.2 ft from the wall — half a spacing. Closer and you get a bright band down the wall; further and the corners go dark.

What to buy, not just how many

676 ft² at 15 footcandles needs 10,140 lumens in the room, which is 282 lumens per fixture — around 4 W in LED.

That is the number to shop by, and it is the one most layout calculators leave out. A 4″ LED downlight typically runs 600–800 lm; a 6″ runs 800–1,200 lm.

Before you cut

Find the joists first. A 6 × 6 grid rarely lands clear of framing on the first attempt, and shifting a can six inches to miss a joist is invisible once the trim is on. Put the whole layout on a dimmer while the wiring is open — it costs almost nothing then and cannot be added cheaply later.

Notes

  • The spacing rule is ceiling height ÷ 2, which gives 4.5 ft here. Rounding to whole fixtures moves it to 4.3 × 4.3 ft — mark the ceiling off the real numbers, not the rule.
  • 282 lumens per can is the figure to shop by. A 4″ LED downlight typically runs 600–800 lm and a 6″ runs 800–1,200 lm, so you could drop to 4″ cans or dim these down.
  • 15 fc is an ambient level, which is what you want here. Recessed lights alone make a room look flat; the fix is lamps and wall light, not more cans.
  • Put them on a dimmer. It costs almost nothing at install, and it is the difference between a ceiling that works at dinner and one that works at 11pm.
  • Check the joists before marking. A 6 × 6 grid rarely lands clear of framing on the first try, and moving a can 6 inches to miss a joist is invisible once the trim is on.

Nearby sizes

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