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A 22 x 22 ft garage shop with average walls and general work needs about 47,000 lumens at 50 footcandles after losses, which is twelve 4,000 lumen 4 ft LED fixtures drawing about 4 A in total; white walls trim it to eleven. Detail benches want twice the light at the bench. The math: lumens = footcandles x area / (utilization x light loss).
Shop lightingUpdates as you type
47,451 lumens: 12 fixtures
- Target
- 50 footcandles on the work plane
- Lumens needed (after losses)
- 47,451
- Fixtures
- 12 at 4,000 lumens
- Layout
- 3 rows of 4, about 7.3 ft between rows
- Load
- 480 W, 4.0 A at 120V (one 15 A circuit holds about 36 fixtures at 80 percent)
Footcandle targets, the utilization factor (0.6) and the 0.85 light loss factor are conventions. Light the bench rows first: aim rows over the benches and the machines, not the center of the room.
LED shop lights
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The footcandle math
Light is measured on the work surface in footcandles. General shop work is comfortable around 50 footcandles; detail work like layout, finishing and reading small marks wants 100. The lumens needed are footcandles x floor area / (utilization x light loss). Utilization is the share of a fixture's light that reaches the work: white walls and ceiling raise it to about 0.7, dark walls cut it to 0.45. Light loss accounts for dirty lenses and ageing LEDs at 0.85.
Where to put the fixtures
Run fixture rows over the benches and machines, not the center of the aisle, so your body does not shadow the work. A dedicated switch for the bench rows gives you the extra detail light without lighting the whole garage. Per-garage counts are in the lighting sizing pages.
Get the garage shop planning checklist
One printable page: measure the bay, count the circuits, list the machines, check the floor. Plus a few short emails, then a couple a month at most.
Unsubscribe anytime. You can also just read the checklist on this site.More garage shop calculators
- Layout and what fits
- Space left with a car
- Workshop amps and subpanel
- 240V circuit sizing
- 240V outlet install cost
- Voltage drop and cords
- Compressor CFM
- Dust collector and duct size
- Garage heater BTU
- Mini-split BTU
- Air filtration ACH
- Workbench height and depth
- Workbench size for a garage
- Mobile base sizing
- Shop budget planner
Frequently asked questions
How many lumens do I need for a garage workshop?
About 2 lumens per square foot of garage after losses for general work at 50 footcandles with average walls, 4 for detail. A 22 x 22 ft bay needs about 47,000 lumens of fixtures for general work.
What color temperature for a shop?
Daylight, around 5000K, is the common choice for shop work because it renders color and grain accurately. 6500K looks bluer and some people find it harsh.
Are linkable LED strips safe on one circuit?
Check the manufacturer's maximum number of fixtures linked end to end, and keep the total at 80 percent of the circuit rating.
This page is researched guidance, not professional electrical, engineering or safety advice. Circuits, loads and clearances depend on your house, your service and your town: have a licensed electrician confirm any wiring, and check local code and each manufacturer's manual before you act.
