Home › Blog › High Bay LED Wattage by Ceiling Height
Published July 24, 2026 · By Industrial Lighting GR Editorial · ~10 min read
For a general-storage warehouse targeting 20 to 30 foot-candles, plan on roughly 100W LED high bays at 12 to 15 feet, 150W at 15 to 25 feet, 200 to 240W at 25 to 30 feet, and 300W or more above 30 feet. Delivered lumens and beam angle matter more than the number on the label, so treat these as starting points, not the final spec.
Wattage is a habit left over from the metal halide era, when a 400-watt fixture meant a known amount of light. LED broke that link. Two 150-watt high bays from different makers can put very different amounts of light on your floor, so the number that actually matters is delivered lumens, not the watts drawn at the panel.
In 2026, a quality commercial LED high bay delivers roughly 130 to 180 lumens per watt, and 150 lumens per watt is a fair baseline to hold a supplier to. Anything much lower is an older or budget fixture. That efficacy is why a modern 120-to-150-watt LED replaces a 400-watt metal halide and still throws more usable light, since LED aims its output down at the work plane instead of wasting it into the roof deck. Industry sizing guidance now leads with delivered lumens for exactly this reason, as the Illuminating Engineering Society recommended-level tables make clear.
Here is the starting point we use for a typical dry-storage warehouse targeting 20 to 30 foot-candles, before we run the real model. Read wattage as "quality LED at 150-plus lumens per watt," because a cheaper fixture at the same wattage will fall short.
| Mounting height | Typical LED wattage | Delivered lumens (approx.) | Notes |
|---|---|---|---|
| 12 to 15 ft | 80 to 100W | 12,000 to 15,000 | Wide beam, close spacing |
| 15 to 20 ft | 100 to 150W | 15,000 to 22,500 | Standard warehouse range |
| 20 to 25 ft | 150 to 200W | 22,500 to 30,000 | Most common high-bay tier |
| 25 to 30 ft | 200 to 240W | 30,000 to 36,000 | Narrower optics, tighter aim |
| 30 to 40 ft | 240 to 300W+ | 36,000 to 45,000+ | Narrow beam, may need aisle-specific optics |
| 40 ft and up | 300 to 480W | 45,000 to 72,000 | Focused optics, specialty design |
Two things move a building off this chart fast. Task areas like detailed assembly, inspection, or pick-and-pack want 30 to 50 foot-candles or more, which pushes wattage up. And spacing is not fixed: hang fixtures farther apart and each one has to work harder. That interplay of height, spacing, and output is what our high-bay fixture layout guide works through in detail.
You cannot pick a wattage until you know how much light the space actually needs, and that comes from the task, not the ceiling. General warehouse storage and bulk aisles usually target 10 to 30 foot-candles. Manufacturing floors and light assembly land around 30 to 50. Fine inspection, detailed bench work, and quality-control stations can call for 50 or more. Getting this target right is the whole ballgame, and we break the standards down by task in our warehouse foot-candle requirements guide.
Pick the target too low and you get dim aisles, safety complaints, and scanner errors. Pick it too high everywhere and you buy fixtures and energy you do not need. The right approach is zoning: hold storage aisles at the lower target and lift the light only where the task demands it.
Light does not fall off in a straight line as it travels down from the fixture. It falls off with the square of the distance. That inverse-square behavior is the single most misunderstood part of high-bay sizing, and it is why you cannot just hang a warehouse fixture wherever it fits.
Here is the practical version. A fixture designed to hit its foot-candle target at 25 feet, hung instead at 35 feet, delivers only about half of its designed light at the floor. Same fixture, same watts, half the useful light, because the beam had ten more feet to spread. Raise the ceiling and you do not just need a bit more wattage. You often need a meaningfully higher-output fixture and a tighter beam to claw that light back.
Two fixtures can share a wattage and a lumen rating and still light a space completely differently, because of beam angle. A wide beam (120 degrees) spreads light over a large area and suits low-to-medium ceilings and open floor. A narrow beam (60 to 90 degrees) concentrates output into a tighter footprint, which is what tall ceilings and narrow racked aisles need to drive light down between the racks instead of onto the tops of them.
Get this wrong and no amount of extra wattage fixes it. A wide beam on a 35-foot ceiling washes the rack faces and leaves the floor dim. A narrow beam on a 15-foot open floor creates bright pools and shadow gaps. Matching optics to height and layout is where a real design separates itself from a box of fixtures off a shelf.
The chart above is a budgeting tool. It tells you roughly what tier of fixture your building lives in and helps you sanity-check a quote. It is not a design. The actual fixture count and wattage come out of a photometric model that accounts for your real mounting height, spacing, ceiling and wall reflectances, rack shadowing, and the foot-candle target for each zone.
That model is also what makes the money side work. Right-sizing avoids the two expensive mistakes: over-lighting, which wastes fixtures and inflates the connected load and the bill, and under-lighting, which fails the spec and gets redone. The payback math on doing it correctly is in our warehouse LED retrofit ROI guide, and you can plug your own square footage and rates into our savings calculator. When you are ready for a real number, the full scope lives on our warehouse LED lighting page.
For a general-storage warehouse with a 25-foot ceiling targeting 20 to 30 foot-candles, most bays land at 150 to 200 watts of quality LED, roughly 22,500 to 30,000 delivered lumens per fixture. The exact number depends on fixture spacing, rack height, aisle layout, and beam angle, which is why a photometric model beats a single wattage rule.
Quality commercial LED high bays deliver about 130 to 180 lumens per watt in 2026, and 150 lumens per watt is a reasonable baseline to hold suppliers to. Efficacy that low signals an older or budget fixture. Higher efficacy means fewer watts for the same light, which lowers both the connected load and the utility bill.
A modern 120 to 150 watt LED high bay typically replaces a 400 watt metal halide fixture and delivers more usable light, because LED puts light where it is aimed instead of wasting it upward. The metal halide also loses output as it ages, so the day-one comparison understates the real-world gain after a couple of years.
Yes, and the drop is steep. Illuminance falls with the square of the distance, so a fixture designed for 25 feet but hung at 35 feet delivers only about half its designed foot-candles at the floor. Taller ceilings need higher-output fixtures and narrower beam optics to keep the same light level on the work surface.
A chart gets you a budget estimate, not a design. Real fixture count and wattage come from a photometric model that accounts for mounting height, spacing, reflectances, rack shadowing, and your target foot-candles. Over-lighting wastes fixtures and energy; under-lighting fails the spec and creates dark aisles. We model every West Michigan warehouse before quoting.
Industrial Lighting GR's editorial is led by senior lighting designers with 15+ years of West Michigan industrial and commercial experience. We run photometric models on every retrofit, spec DLC-qualified fixtures by environment and mounting height, match beam optics to ceiling height and aisle layout, and carry Consumers Energy and DTE rebate paperwork through pre-approval, install, and final payment. We serve Grand Rapids, Wyoming, Kentwood, Walker, Holland, Muskegon, Kalamazoo, and surrounding West Michigan warehouse and manufacturing facilities.