What you need to know
- Measure lux where the task happens, not only in the middle of the room.
- Different tasks need different amounts and directions of light.
- More watts do not necessarily mean more useful light.
Use your own measurements
BricoDato tools help turn the guide into quantities, kWh, cost or a project plan.
Lumens vs lux
Lumens describe the total visible light from a source. Lux describes how much of that light falls on each square metre of a surface.
Measure where you use the light
For a desk, measure at desk height; for a kitchen, at the worktop; for general lighting, take several points rather than relying on one spot.
Treat target values as guidance
Recommended lux values vary by task, age, contrast and local standards. Use measured comfort and task performance alongside generic ranges.
Improve distribution before adding power
Better luminaire placement, task lighting and lighter surfaces can improve useful illumination without simply installing higher-watt lamps.
Final check
Before buying material or doing the work, review the assumptions and technical limits that matter for your specific product, room or installation.
- Measure at the task surface.
- Take several readings.
- Compare lumens and beam distribution.
- Improve placement before increasing wattage.
Keep a small job sheet
Record the measurements, product reference, technical values you used, date and final result. For maintenance or diagnostics, also note the conditions at the time. A short written record makes future comparisons much more reliable.
Turn the guide into a decision
Use your measurements and the manufacturer’s technical data. If the decision affects fixed electrical work, structure, hidden leaks, refrigerant systems or another safety-critical installation, consult a qualified professional.