How Many Lumens Does Your Warehouse Need? A Practical Guide to High Bay Lighting

First, the units

• Lumens measure the total light a fixture produces.

• Lux measures how much of that light lands on a surface, in lumens per square metre.

• Foot-candles (fc) measure the same thing in lumens per square foot.

• 1 foot-candle is about 10.76 lux.

When people talk about “candles” for a warehouse, they almost always mean foot-candles, not candela. Candela describes a fixture’s intensity in one direction, while lux and foot-candles describe the light that reaches the floor, which is what you are designing for.

Step 1: Choose your target light level

Light needs depend on the work being done. These are common ranges based on Illuminating Engineering Society (IES) guidance:

Always check your client’s requirements and the current IES and code guidance for your site, since the right level depends on the work.

Step 2: Use the lumen method

• CU (coefficient of utilization) is the share of a fixture’s light that actually reaches the work surface. It depends on mounting height, wall and ceiling reflectance, and the fixture’s light distribution.

• LLF (light loss factor) accounts for dirt build-up and light output falling over time. Using it keeps the space bright years after installation, not only on day one.

Worked example: 100 × 150 ft picking warehouse

• • Area: 100 ft × 150 ft = 15,000 sq ft

  • Target: 250 lux (about 23.2 fc), suitable for picking

  • Mounting height: 25 ft

  • CU: 0.65 | LLF: 0.75

  • Light needed on the floor: 15,000 sq ft × 23.2 fc = about 348,000 lumens

  • Adjust for losses:348,000 ÷ (0.65 × 0.75) = about 715,000 lumens

  • Choose a fixture:with 24,000-lumen LED high bays, 715,000 ÷ 24,000 = about 30 fixtures

Laid out in 5 rows of 6, that is roughly 20 ft by 25 ft spacing, which is reasonable for a 25 ft mounting height.

Mistakes to avoid

• Shopping by watts. Efficiency differs between fixtures, so compare lumens and light distribution.

• Ignoring racking. Tall racks block light, so aisles can need different spacing or fixture types than open floor space.

• Skipping light loss. A design with no allowance for dirt will be too dim within a few years.

• Buying before a layout. For high racking, strict standards, or large spaces, confirm the estimate with a photometric layout before ordering.

• Overlooking emergency and exit lighting. These are designed separately and are required in addition to your general lighting.

• Using uncertified fixtures. Fixtures installed in Canadian buildings need approved certification, such as CSA or cUL marks, and incentive programs typically cover only products on their approved lists.

Why the estimate isn’t the final design

The lumen method gets you close fast, which is useful for budgeting and for comparing options. A professional layout uses the actual fixture’s photometric data to check how even the light is, whether the aisles are properly lit, and whether glare is under control.

What the installation involves

Commercial lighting is electrical work, so installation should be done by licensed electricians who follow the Canadian Electrical Code and handle any required permits. A good installer also plans around your operations, with phased work and safe access so you don’t lose a shift.

Work with a team that handles the whole project

ATA Technical Group is a commercial electrical and general contractor in Coquitlam serving warehouses and commercial facilities across the Lower Mainland. Our Red Seal electricians and FSR-designated contractor can assess your space, recommend the right fixtures, and install them safely and on schedule. As a member of the BC Hydro Alliance of Energy Professionals, we can also help plan energy-saving lighting upgrades.

Request a free estimate for your warehouse lighting project, or send us a message with your floor area, ceiling height, and current fixtures.

Frequently asked questions

• How many lumens per square foot does a warehouse need? It depends on the work. As a rough guide, general storage needs about 10 to 15 foot-candles, picking about 15 to 25, and detailed work more than that.

• Is more light always better? No. Too much light wastes energy and can cause glare, so design to the target for the task.

• How often should warehouse lighting be maintained? Cleaning fixtures and checking for failures regularly helps the system keep delivering the light you designed for.