Construction lighting planning
A flood light must cover the work area without wasting light. Beam angle links three practical items. They are throw distance, beam diameter, and mounting geometry. When any two values are known, the third value can be estimated. This calculator helps a site planner test those choices before ordering fixtures or drilling brackets.
Why beam angle matters
A narrow beam sends light farther. It suits high poles, long yards, gate entrances, and security lanes. A wide beam spreads light quickly. It suits loading bays, slab pours, scaffolds, and temporary work zones. Very wide beams may reduce glare pockets, but they can also lower center brightness. The best choice balances reach, overlap, and required visibility.
Using layout numbers
Mounting height and horizontal offset create a slant throw. That slant distance is the real path from the lamp to the lit surface. If you already measured throw distance, use direct distance. If the pole or wall position is fixed, use height and offset. The calculator then shows the coverage diameter at the target plane.
Fixture spacing and overlap
Construction sites rarely use one flood light. Several units usually share a row. Overlap reduces dark bands between beams. A small overlap saves fixtures. A larger overlap improves uniformity near walkways, ramps, and equipment paths. Spacing is estimated by reducing the beam width by the selected overlap percentage.
Brightness estimate
The lux result is an average guide. It uses useful lumens, light loss factor, and utilization. Real results vary with lens shape, surface reflectance, dirt, voltage drop, aiming, and obstruction. Final projects should still be checked with a light meter or a formal photometric plan.
Practical advice
Use the calculator early during layout planning. Compare several angles before buying fixtures. Keep glare away from operators, drivers, neighbors, and cameras. Record the chosen angle, spacing, and mounting notes. Export the result for the method statement, inspection file, or procurement request.
For critical paths, check more than one scenario. Night work, wet ground, dust, and moving plant can change visibility fast. Test a conservative angle, then compare a wider beam. A simple comparison often reveals whether more fixtures or a better mounting point will give the safest result for crew movement and access.