Lighting Design Basics: Lux & Control
A clear introduction to lighting design: the difference between lumens and lux, how target illuminance levels are set for different tasks, the role of colour temperature and glare, and how lighting controls save energy in UAE buildings.
Lighting design is the engineering of getting the right amount and quality of light onto the right surfaces, efficiently and comfortably. It is far more than choosing fittings: it balances how much light reaches a task, how evenly it is spread, how the light appears, and how much energy the installation uses over its life.
Good lighting improves safety, productivity and comfort; poor lighting causes glare, eye strain and wasted energy. In the UAE, where lighting runs for long hours in offices, retail, industrial and public buildings, well-designed lighting with effective controls is both a comfort issue and an important contributor to a building’s energy performance.
How it works
The starting point is the difference between lumens and lux. Lumens measure the total light output of a lamp or luminaire. Lux measures illuminance — the amount of light actually falling on a surface, in lumens per square metre. A bright lamp high in a large room may still give low lux on the floor, so design works from the lux level the task needs, not just the lamp output.
Each type of space has a recommended maintained illuminance for the task performed there: low levels suit circulation and storage, higher levels suit offices and reading, and the highest levels suit detailed work such as drawing or inspection. The designer selects luminaires, their output, spacing and mounting height so the calculated lux meets the target across the working area, allowing for light loss as lamps age and surfaces gather dust.
Quality matters as much as quantity. Uniformity describes how evenly light is distributed, avoiding bright and dark patches. Glare — light that is too bright or badly positioned in the field of view — is controlled by luminaire design, position and shielding. The colour temperature of the light, measured in kelvin, sets its appearance from warm to cool, and the colour rendering index (CRI) describes how faithfully it shows colours.
Efficiency is captured by efficacy — the lumens produced per watt of electrical power. LED sources have far higher efficacy than older incandescent and most discharge lamps, producing more light for less energy and far longer life, which is why they now dominate new design. Choosing efficient sources and the right optics reduces both energy use and the cooling load the lighting adds.
Lighting controls multiply these savings. Occupancy and presence sensors switch or dim lights when areas are unused; daylight (photocell) controls dim electric light when natural light is available; time schedules and zoning match lighting to how spaces are actually used. Modern controls integrate with the building management system so lighting is coordinated with occupancy, daylight and the building’s wider energy strategy.
Main types
In the UAE
- Energy-efficient lighting and controls support Abu Dhabi's Estidama Pearl Rating System and the UAE's wider energy-efficiency goals, since lighting runs for long hours and adds to the cooling load.
- Lighting products and drivers are subject to UAE federal standards and conformity assessment under ESMA, and emergency and escape lighting must meet the UAE Fire and Life Safety Code of Practice.
- Target illuminance levels follow recognised international lighting practice (such as CIE/EN guidance) as applied in UAE design, with controls increasingly integrated into building management systems.
How GPR applies this
GPR designs and installs lighting for offices, retail, industrial and residential projects across Abu Dhabi, selecting efficient LED luminaires and optics to meet target lux levels with good uniformity and controlled glare. We design layouts to the task and space, specify colour temperature and CRI to suit the use, and integrate occupancy, daylight and scheduling controls with the building management system so lighting is comfortable, compliant and energy-efficient.
Frequently asked questions
What is the difference between lumens and lux?
Lumens measure the total light a lamp produces; lux measures how much of that light actually falls on a surface (lumens per square metre). Design works to the lux a task needs.
How much light does a space need?
It depends on the task: lower illuminance for circulation and storage, higher for offices and reading, and the highest for detailed work, following recognised lighting recommendations.
What does colour temperature mean?
Measured in kelvin, it describes the appearance of the light from warm (lower values) to cool (higher values), chosen to suit the space and its use.
Why is LED lighting more efficient?
LEDs have much higher efficacy — more lumens per watt — and far longer life than incandescent and most discharge lamps, so they produce more light for less energy and lower the cooling load.
How do lighting controls save energy?
Occupancy sensors, daylight dimming, scheduling and zoning reduce lighting when it is not needed, and integrating them with the BMS coordinates lighting with how the building is actually used.