Warehouse high bay lighting design: the inputs before the fixture
The racking, the roof and the shift decide the scheme. The fixture schedule is the last document, not the first.
A warehouse lighting design is decided before a fixture is chosen. The racking layout sets the geometry, the roof structure sets the mounting height, the work sets the level the space has to hold, and the way the building runs decides whether controls earn their cost. Put those four inputs on one page and the fixture schedule follows. Skip one and the tender compares quotations that were never designed to the same brief.
The racking decides the lighting
An aisle is lit for the pick face and for the floor, not for the roof. Rack height, aisle width and the level of the pick decide whether the scheme works from above the rack or from a lower mounting height along the aisle, which gives very different fixture counts.
Bulk storage is a different job: a wide working plane, with the level set by the task and the uniformity by how the space is used. A racking drawing with heights and aisle widths is the first document to ask for.
Mounting height and the roof
The luminaire hangs from something. Truss depth, purlin spacing, sprinkler and duct routes and the height of the forklift mast all constrain where a fitting can go and how it can be aimed. A design that ignores the structure is a design that gets changed on site.
Service access belongs to the same decision. A fitting that needs a scissor lift every time it is cleaned costs more over its life than one reached from a walkway, and the maintenance factor should reflect how often it is cleaned.
Uniformity, glare and the working plane
A bright pool under each fixture is not a lit warehouse. The uniformity ratio is what stops a picker walking from a bright aisle into a dark one, and the glare rating matters where people look up at the rack or drive toward a fixture.
The maintained level and the uniformity come from the project's lighting requirement, normally written against EN 12464-1 for indoor work places, and they belong in the brief before the schedule. The specification sheet confirms them.
Controls and the payback the buyer runs
Daylight dimming along the roof lights, occupancy sensing in low traffic aisles and a switching plan that follows the shift are the controls that usually pay. Each needs a sensor position and a zone on the drawing, and a control that is not commissioned gets bypassed.
The payback is the buyer's calculation, with the buyer's tariff and hours. A supplier can give the load figure and the control scheme; the electricity price and the operating hours are not the supplier's to guess.
Four areas, four geometries
The same building contains four lighting jobs, and they do not share a fixture.
| Area | What is lit | Mounting | Distribution | Check |
|---|---|---|---|---|
| Racking aisle | Pick face and floor | Above the rack or in the aisle | Narrow, along the aisle | Rack height, aisle width |
| Open floor | Working plane over a wide area | High, from the structure | Wide, overlapping | Uniformity across bays |
| Loading dock | Trailer interior and apron | Canopy or wall | Asymmetric, out and down | Glare for a reversing driver |
| Cold store | Aisles at low temperature | As the aisle, sealed | As the aisle | Temperature rating, access |
A building usually needs two or three of these. A brief that names only the open floor comes back as a variation.
Five things to confirm before the order
Each one changes the calculation, the count or the control scheme.
- The racking drawing, with heights and aisle widths.
- The mounting height the structure allows, and how a fitting is serviced.
- The maintained level and uniformity the project requires, and who signs them.
- The operating hours and the tariff the payback will use.
- Who commissions the controls, and what the handover test is.
- Design brief
- Warehouse lighting
- Ask for
- Calculation for the layout, specification sheet, control scheme
- Decided per
- Area and task, not per building
Three answers before the email
How many high bays will the building need?
The count comes from the calculation, not from floor area divided by a rule of thumb. Mounting height, distribution and the uniformity asked for change it more than the square metres do.
Can the existing positions be reused?
Sometimes, and the calculation is what proves it. A retrofit that keeps the positions has to reach the same maintained level with a new distribution, and the old spacing may not suit it.
Why is no wattage quoted on this page?
Because the wattage follows the design. The level, the mounting height and the distribution decide the fixture. The specification sheet for a model states the figures the calculation used.
Send the racking drawing and the hours.
A layout, a mounting height and the level the project requires is enough to quote a calculation and a schedule.