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LuxPlan
168 sq ft · 300 lux target

12×14 home office:
12 lights

12 fixtures A 12×14 ft home office (168 sq ft) needs approximately 12 recessed lights at 800 lumens each — about 10,390 lumens in total — laid out 4 across by 3 deep.

Space them 3.5 ft apart along the 14 ft wall and 4 ft apart along the 12 ft wall, starting 1.8 ft from the end walls.

Fixtures12at 800 lm each
Total lumens10,390to hit 300 lux
Spacing3.5′× 4′ apart
Wall offset1.8′from the end wall

The ceiling plan

Drawn to scale, with each fixture at its computed position and the pale circles showing roughly where each one lands on the working plane.

14 ft 12 ft 4 across × 3 deep · 3.5 ft × 4 ft apart · 1.8 ft from the end walls

Same room, different fixtures

If you have already chosen a fitting, read across from its lumen output.

Fixture outputRough equivalentFixtures neededSuggested grid
450 lm 40 W incandescent 255 × 5
650 lm 50 W incandescent 164 × 4
800 lm 60 W incandescent 124 × 3
1000 lm 75 W incandescent 93 × 3
1200 lm 100 W incandescent 93 × 3

Fewer, brighter fixtures give more contrast; more, dimmer fixtures give flatter, more even light. Both rows deliver the same total.

How the 12 was calculated

Target illuminance for a home office300 luxpublished range 400–500 lux
Floor area15.6 m²168 sq ft
Mounting height above the working plane5.5 ft8 ft ceiling, 2.5 ft working plane
Room index1.17(L × W) ÷ (Hm × (L + W))
Utilisation factor0.56from the room index, light surfaces
Maintenance factor0.8dirt and lamp depreciation
Lumens required10,390 lm300 × 15.6 ÷ (0.56 × 0.8)
Fixtures at 800 lm12delivering about 277 lux

The brightest room on this list. The ceiling layer is sized to 300 lux and a desk lamp is assumed to take the working plane the rest of the way — lighting a whole office to 500 lux from the ceiling alone is glary and wasteful.

Other ceiling heights

CeilingFixturesGridSpacingMax spacing
8 ft124 × 33.5′ × 4′7.2′
9 ft164 × 43.5′ × 3′8.5′
10 ft164 × 43.5′ × 3′9.8′
12 ft164 × 43.5′ × 3′12.4′

Questions

How many recessed lights do I need for a 12x14 home office?

About 12 fixtures at 800 lumens each, arranged 4 across by 3 deep. That gives roughly 277 lux across 168 square feet, against a target of 300 lux for a home office.

How many lumens does a 12x14 home office need?

Roughly 10,390 lumens in total. That comes from 300 lux over 15.6 m², divided by a utilisation factor of 0.56 and a maintenance factor of 0.8 — the light that never reaches the working plane has to be paid for up front.

How far apart should the lights be in a 12x14 room?

3.5 ft apart along the 14 ft wall and 4 ft apart along the 12 ft wall, with the outer row about 1.8 ft in from the end walls — half a spacing. With a 8 ft ceiling the maximum sensible spacing is around 7.2 ft before the floor starts to show scallops.

Does the ceiling height change the answer?

Yes, in two ways. A higher ceiling spreads each fixture's light over a wider area, so fixtures can sit further apart — but it also drops the light level reaching the floor, so a taller room generally needs more total lumens. At 8 ft the room index works out at 1.17, giving a utilisation factor of 0.56.

Computed with the lumen method — see how it works and where it is weak. Planning guidance only, not an electrical design. Fixture counts are a starting point — follow your local wiring rules and use a licensed electrician for the installation.

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