Lighting sample comparison in a project studio
Room · task · budget

Legrand Lighting Guide

Use five practical questions to turn a broad product search into a shortlist that can be tested and documented.

Begin with the decision, not a favorite fixture

A useful lighting brief names what people need to see, when the space changes and who will maintain it. In an office that may mean comfortable screen work and daylight response; in retail it may mean precise beam placement and faithful material color. Establish mounting height, room reflectance, target illuminance, CCT and control responsibility before comparing appearance or price.

Budget works best as a whole-system boundary: luminaires, drivers, sensors, commissioning access and future service labor all belong in the conversation.

Photometric files let the design team test distribution in the real geometry. LM-79 data describes measured product performance, while LM-80 and TM-21 inform lumen-maintenance projection. These documents answer different questions and do not predict every installed condition.

Five questions for a better shortlist

Separate horizontal work, faces, displays and circulation. Each may call for a different balance of illuminance, vertical light, beam angle and glare control.

Maximizing lm/W can reduce power, yet the highest value may not provide the preferred distribution, UGR, CRI or spatial appearance. Compare calculated results and a sample under representative finishes.

Centralized systems simplify common policy and monitoring. Distributed zones can improve local flexibility and fault isolation. Existing wiring, scale and commissioning skills often decide which architecture is practical.

Integrated assemblies can be compact and thermally coordinated. Replaceable drivers and light engines may ease long-term service. Confirm access, compatibility and parts strategy before treating either choice as lower cost.

Request the exact model's IES or LDT file, power factor, THD, IP rating, control interface and certification scope. Validate critical appearance with a mock-up; calculation accuracy depends on geometry and reflectance inputs.

Evidence to put beside the sample

IES distribution reviewCCT material comparisonOccupancy control commissioning

Turn your room brief into a testable shortlist

We can organize the decision criteria and the evidence to request. Final photometric, electrical and code approval remains with the responsible project professionals.