Lighting Design
Choosing and placing light so spaces work, look right, and use less energy.
Quick Answer
Lighting design is the engineering and architectural practice of selecting, locating, and controlling light fixtures so a space has the right illumination for its tasks. It balances light levels, glare, color, aesthetics, and energy use. Energy codes limit lighting power and require controls, so design choices directly affect compliance and operating cost.
The Full Picture
Lighting design starts with what people will do in a space. An open office, a corridor, a surgical suite, and a warehouse each need different light levels, uniformity, and glare control. Designers translate those needs into a layout of fixtures, specify each fixture's output and distribution, and verify the result with photometric calculations that predict how much light lands on work surfaces.
Beyond quantity of light, designers weigh color quality, color temperature, glare, and the relationship between daylight and electric light. Daylight can offset electric lighting when controls dim or switch fixtures in response, which links lighting design closely to the architecture and the energy strategy of the building.
Controls are as important as fixtures. Occupancy sensors, daylight sensors, scheduling, and dimming reduce energy and are often required by energy codes. Codes such as ASHRAE 90.1 and the IECC also set lighting power allowances by space type, so a design that looks fine can still fail compliance if it installs too many watts per square foot.
For contractors, lighting design shows up as fixture schedules, reflected ceiling plans, control sequences, and long-lead fixture packages. Clear coordination between electrical, architectural, and ceiling drawings helps avoid fixtures that conflict with ducts, sprinklers, or ceiling grids.
Real Examples
Common Misconceptions
People assume: More light always means better lighting.
Actually: Good design targets the right amount of light in the right place. Excess light wastes energy, can cause glare, and may exceed the lighting power limits in the energy code.
People assume: Lighting design is just choosing attractive fixtures.
Actually: Fixture appearance is one factor. Photometrics, controls, glare, daylight integration, and code compliance all drive the design.
Frequently Asked Questions
What does a lighting designer do?
A lighting designer specifies fixtures, layout, light levels, and controls for a space, checks the result with photometric calculations, and coordinates with architects, electrical engineers, and interior designers.
What is lighting power density?
Lighting power density is the installed lighting wattage divided by floor area, typically expressed in watts per square foot. Energy codes set maximum allowances by building or space type.
Why do energy codes require lighting controls?
Controls such as occupancy sensors, daylight sensing, and dimming cut the hours lights run at full output. Energy standards require them in many space types to reduce energy consumption.
How does lighting relate to the reflected ceiling plan?
The reflected ceiling plan shows fixture locations alongside ceiling grids, diffusers, and sprinklers, so it is a key coordination drawing for lighting.