Warm Lighting Basics You Should Know

Warm lighting feels natural to us in the evenings and promotes relaxation. Our circadian rhythm (the body and brain's natural 24-hour cycle of changes) relies on warm lighting to help us unwind, relax, and prepare for sleep. On the other hand, cool lighting helps us stay alert and energetic for tasks and can interfere with our inner clock during the evening hours before sleep.

Learn more about warm lighting, where to use it, and how to distinguish it from cool lighting.

Warm vs. Cool Lighting

Light bulbs emit either a warm or cool (daylight) color. A higher temperature is a cooler light. However, in simple terms, warm light is reddish in appearance, and cool light looks bluish. This way of looking at lighting is similar to understanding warm and cool colors.

Warm lighting emits subtle reddish and yellowish hues, taking on a softer glow but can be tough on the eyes when trying to accomplish tasks that require bright lighting. Cool lighting emits whiter, bluer "daylight" hues on a clear, bright day for an intense but harsher look.

The Color Temperature Scale

Warm or cool lighting is determined by color temperature (measured in kelvins). A lower temperature is a warmer light. A higher temperature is a cool light.

Warm Color Temperatures

Colors on the color temperature scale that range from about 2700K to 3000K (sometimes up to 3500K) are called warm colors. These reddish or yellowish whites were typical of older incandescent bulbs.

Sunset and sunrise typically feature light in the warm color temperature range, a bit lower in number (about 1800K) than the light of a warm bulb. Candle and match flames typically range from 1700K to 2200K.

Cool Color Temperatures

Anything over 4000K on the color temperature scale is considered cool lighting. Moonlight is a bit bluer or cooler, in the 4100K range since it is very bright. Bulbs used in hospitals and other commercial spaces have very high cool color temperatures.

Why Warmer Colors Resonate With Us in the Evening

Perhaps warmer colors resonate with us for the evening because of the color of the evening hearthside fire. Warm light in the early morning, as might come through an east-facing window, can also be comforting and ease us into wakefulness.

Most of us have both types of lighting sources to create moods. Open curtains or blinds during the daytime to let in warm, early morning sun and cooler daylight later in the day. Lamps, a fireplace, or a firepit at night provide warmer ambient lighting. We probably turn on a task light with a cool light bulb to help us read at night.

Warm Colors Change Our Perception

Warm lighting changes our perception of the color of objects within the room from how they would look in daylight. If your room is lit with mostly warm light, your furniture or other decor may look very different in cool light.

Too much warm light also breaks our concentration on tasks, which is why workspaces are often lit with cool lights.

Where Should I Use Warm Light?

Warm, or soft white, light, is especially appropriate for cozy living spaces where we want to feel relaxed and comfortable. Use warm lighting to simulate evening or very early morning light. Warm lights look better in many period rooms and those decorated with warm colors and paint.