5 signs of healthy, comfortable building lighting

This blog post was authored by Kelsey Rowe, PE, CLD, Partner and Senior Electrical Engineer, Design Collaborative.

When we talk about healthy buildings, one of the most influential components is lighting.

Lighting affects visual comfort, circadian health, mood, and energy usage.

The great thing is: you don’t need to be a lighting designer to spot the basics. There are five simple cues—rooted in lighting science, the Illuminating Engineering Society (IES), and the WELL Building Standard—that anyone can evaluate in minutes. These cues signal whether a building is positioned for high-performing, comfortable environments or whether hidden costs and complaints may be waiting after move-in.

Let’s walk through five signs to look for.

5 Signs of Healthy and Comfortable Building Lighting

1. Daylight Access + Daylight Control

Daylight is a major contributor to circadian health and overall alertness. It’s also something people notice the second they walk into a building.

2. Glare + Visual Comfort

Glare is one of the most common complaints in commercial buildings. It typically shows up as:

• Visible LEDs or “high-angle brightness”
• Hot spots on glossy floors or work surfaces
• Bare lamps or unshielded pendants
• Computer screen reflections that make work difficult

Healthy lighting, on the other hand, includes:

• Fixtures with diffusers or indirect lighting to soften the luminance
• Good shielding angles to hide the light source
• Balanced luminance ratios to ward off visual fatigue and glare
• Smooth, even ceiling illumination to prevent bright patches

Visual comfort is a core requirement in the WELL Building Standard and something people intuitively sense the moment they walk into a building.

3. Color Quality + Color Consistency

With LED technology, we can control not only how much light a fixture produces, but also how accurately it renders color. That can dramatically impact the look and feel of a space.

Look for these indicators of healthy color quality:

• Color Rendering Index (CRI) of 80–90%
  This measures how accurately colors appear compared to natural daylight.
• Consistent Correlated Color Temperature (CCT) across fixtures
  Most commercial environments perform well in the 3500K–4000K range.
• No visible mix of warm and cool lamps
  That “patchwork” effect often results from ad-hoc replacements and usually signals a lack of an intentional lighting strategy.

When color quality is off, the whole space suffers—people look tired, finishes look flat, and carefully selected materials lose their impact. Well-coordinated, high-quality LED lighting signals care and intentionality. It reflects a building that’s been designed and maintained with purpose, not patched together over time.

4. Adaptive Lighting Controls

Healthy buildings rely on lighting that adapts to daylight, occupancy, and the tasks being performed.

Key systems to identify:

• Occupancy + vacancy sensors. Lights turn off automatically when a space isn’t being used.
• Daylight harvesting. Photo sensors reduce electric light when daylight is adequate and increase it as daylight fades.
• Scheduling controls. Prevent wasted overnight lighting, reduce light spill to neighboring properties, and ensure consistent appearance for building users.
• Multi-level or zoned dimming. Allows users to customize their light levels depending on the activity.
• Tunable white lighting. Adjusts color temperature throughout the day, mimicking natural daylight patterns.