Lighting design and downlight spacing calculator
Get a useful first estimate for the light level, total lumens, fitting quantity and installed load across common commercial spaces. It gives you the basics clearly, without pretending to replace a photometric lighting design, and links into the relevant commercial product ranges when the estimate is ready to narrow.
Build the first estimate.
Choose the closest space type, then enter the lit area and ceiling height.
Choose a space type to begin.
The result will show the starting light level, total lumens, indicative fitting quantity and installed load.
No result has been calculated yet.
Floor area and the starting light level, adjusted by the application allowance.
Rounded up against the primary model output.
Based on the selected model wattage.
Set from the selected commercial space type.
Choose a use case to set the light level.
Select an application to populate this.
The useful basics, kept in proportion.
Choose a commercial space type to see how the starting light level, floor area and matched luminaire output become an indicative quantity.
Set a starting level
The space type provides a practical initial lux assumption.
Estimate total light
Area and the application allowance produce a whole-room lumen requirement.
Compare a fitting quantity
Real Lumenloop model outputs provide an indicative count and installed load.
Commercial luminaires matched to the estimate.
The shortlist uses the selected space type, mounting preference, priority and real model output. Confirm the final model, optics, controls and emergency options against the product information.
Request specification support.
Add the project details already known. The calculated area, starting light level, lumen requirement, fitting quantity and suggested range are included with the enquiry.
A first lighting estimate, not a finished design.
The calculator uses a simple lumen method for an early whole-room estimate. Floor area is multiplied by the starting light level for the chosen room type, then adjusted by a broad utilisation allowance. The suggested fitting quantity is based on the output of a matched Lumenloop model and rounded up.
The result does not calculate point-by-point illuminance, uniformity, glare, vertical light, emergency-lighting positions or luminaire-specific photometry. Use it to establish a sensible first quantity and output range before the room geometry, optics and final layout are confirmed. Office, retail and warehouse projects can then be narrowed through the relevant product ranges, controls and mounting style.
Compare the result with the relevant commercial lighting ranges, or review dedicated information for office lighting, retail lighting and warehouse and industrial lighting.
What does the calculator include?
A starting light level, whole-room lumen requirement, indicative fitting count, installed load and a shortlist of relevant commercial luminaires.
Why does the application matter?
Different commercial spaces begin with different task-lighting needs, ceiling heights and likely luminaire types. The application choice sets those first assumptions and changes the product shortlist.
Can I use the result as a lighting layout?
No. The fitting count is an early quantity estimate. It does not position luminaires or prove uniformity, glare control, emergency provision or compliance.
What should be checked next?
Confirm the room dimensions, reflectances, ceiling construction, working plane, optics, controls, emergency provision and product photometry before the final luminaire schedule is issued.