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LuxPlan
168 sq ft · 150 lux target

12×14 garage:
9 lights

9 fixtures A 12×14 ft garage (168 sq ft) needs approximately 9 recessed lights at 800 lumens each — about 6,196 lumens in total — laid out 3 across by 3 deep.

Space them 4.7 ft apart along the 14 ft wall and 4 ft apart along the 12 ft wall, starting 2.3 ft from the end walls.

Fixtures9at 800 lm each
Total lumens6,196to hit 150 lux
Spacing4.7′× 4′ apart
Wall offset2.3′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 3 across × 3 deep · 4.7 ft × 4 ft apart · 2.3 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 164 × 4
650 lm 50 W incandescent 93 × 3
800 lm 60 W incandescent 93 × 3
1000 lm 75 W incandescent 63 × 2
1200 lm 100 W incandescent 42 × 2

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

How the 9 was calculated

Target illuminance for a garage150 luxpublished range 150–300 lux
Floor area15.6 m²168 sq ft
Mounting height above the working plane8 ft8 ft ceiling, measured to the floor
Room index0.81(L × W) ÷ (Hm × (L + W))
Utilisation factor0.47from the room index, light surfaces
Maintenance factor0.8dirt and lamp depreciation
Lumens required6,196 lm150 × 15.6 ÷ (0.47 × 0.8)
Fixtures at 800 lm9delivering about 174 lux

A plain storage garage sits at the low end; if you actually work on things in there, design for the top of the range or higher.

Other ceiling heights

CeilingFixturesGridSpacingMax spacing
8 ft93 × 34.7′ × 4′10.4′
9 ft93 × 34.7′ × 4′11.7′
10 ft93 × 34.7′ × 4′13′
12 ft93 × 34.7′ × 4′15.6′

Questions

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

About 9 fixtures at 800 lumens each, arranged 3 across by 3 deep. That gives roughly 174 lux across 168 square feet, against a target of 150 lux for a garage.

How many lumens does a 12x14 garage need?

Roughly 6,196 lumens in total. That comes from 150 lux over 15.6 m², divided by a utilisation factor of 0.47 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?

4.7 ft apart along the 14 ft wall and 4 ft apart along the 12 ft wall, with the outer row about 2.3 ft in from the end walls — half a spacing. With a 8 ft ceiling the maximum sensible spacing is around 10.4 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 0.81, giving a utilisation factor of 0.47.

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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