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LuxPlan
64 sq ft · 100 lux target

8×8 hallway:
2 lights

2 fixtures A 8×8 ft hallway (64 sq ft) needs approximately 2 recessed lights at 800 lumens each — about 1,858 lumens in total — laid out 1 across by 2 deep.

Space them 8 ft apart along the 8 ft wall and 4 ft apart along the 8 ft wall, starting 4 ft from the end walls.

Fixtures2at 800 lm each
Total lumens1,858to hit 100 lux
Spacing8′× 4′ apart
Wall offset4′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.

8 ft 8 ft 1 across × 2 deep · 8 ft × 4 ft apart · 4 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 42 × 2
650 lm 50 W incandescent 42 × 2
800 lm 60 W incandescent 21 × 2
1000 lm 75 W incandescent 21 × 2
1200 lm 100 W incandescent 11 × 1

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

How the 2 was calculated

Target illuminance for a hallway100 luxpublished range 100–200 lux
Floor area5.9 m²64 sq ft
Mounting height above the working plane8 ft8 ft ceiling, measured to the floor
Room index0.5(L × W) ÷ (Hm × (L + W))
Utilisation factor0.4from the room index, light surfaces
Maintenance factor0.8dirt and lamp depreciation
Lumens required1,858 lm100 × 5.9 ÷ (0.4 × 0.8)
Fixtures at 800 lm2delivering about 86 lux

Circulation space. Even spacing matters more than total output — patchy hallways read as gloomy no matter how many lumens you install.

Other ceiling heights

CeilingFixturesGridSpacingMax spacing
8 ft21 × 28′ × 4′10.4′
9 ft21 × 28′ × 4′11.7′
10 ft21 × 28′ × 4′13′
12 ft21 × 28′ × 4′15.6′

Questions

How many recessed lights do I need for a 8x8 hallway?

About 2 fixtures at 800 lumens each, arranged 1 across by 2 deep. That gives roughly 86 lux across 64 square feet, against a target of 100 lux for a hallway.

How many lumens does a 8x8 hallway need?

Roughly 1,858 lumens in total. That comes from 100 lux over 5.9 m², divided by a utilisation factor of 0.4 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 8x8 room?

8 ft apart along the 8 ft wall and 4 ft apart along the 8 ft wall, with the outer row about 4 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 0.5, giving a utilisation factor of 0.4.

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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