Lighting Basics: Colour Temperature in Interior Design

Understanding the concept of colour temperature is crucial for interior designers aiming to create spaces that are both functional and aesthetically pleasing. Colour temperature describes the hue emitted by a light source, revealing whether the light is warm or cool. This seemingly simple metric has profound implications on the perception, mood, and usability of a space. Learn more about the basics of colour temperature and feel confident in designing your space with the perfect lighting scheme suited for your unique needs.

What is Colour Temperature?

Colour temperature (sometimes called Correlated Colour Temperature or CCT) refers to the appearance of light provided by a light source, expressed in degrees of Kelvin. In lighting for interior design, the scale ranges from warm, lower colour temperatures (2,000K to 3,000K) which emit a yellowish light, to cool, higher temperatures (4,500K and above), which produce a bluish-white light. This metric isn’t just a technical specification; it’s a crucial element in setting the right atmosphere for a room. It is similar to the glow of metal when applied heat at varying temperatures — it glows from warm reds to bright blues as the metal becomes hotter.

Image from Wikipedia. A heated iron bar glows red when heated. You can tell the temperature of the metal rising and heating up by observing the colour of the glow becoming cooler (bluish in colour).

Cool white light (3,000K to 4,000K) offers a more neutral white that balances warmth with the clarity of blue tones. It’s suitable for kitchens, bathrooms, and workspaces, where clarity and focus are needed. The brightest option, daylight white (above 4,500K), mimics natural sunlight and is excellent for areas requiring maximum visibility and alertness, such as study areas, operating rooms, or construction sites.

What is the Right Colour Temperature for Your Space?

A common question we get is how to determine the correct colour temperature for a given space. Though there are no hard and fast rules, and preference is subjective, we offer guidelines for achieving your desired aesthetic and atmosphere. We suggest letting the function of the space and your desired ambiance lead your choice of colour temperatures.

Residential spaces and restaurants often benefit from warmer tones, enhancing comfort and intimacy. We recommend a colour temperature between 2,700K and 3,000K for these settings. In contrast, cooler colour temperatures are ideal for more functional spaces or areas with a specific focus. For office environments, we suggest above 3,000K, while retail spaces, hospitals, and medical clinics should use above 4,000K to ensure clarity and promote an atmosphere of alertness.

For bedrooms, we recommend going with colour temperatures under 3,000K for a more relaxed atmosphere that soothes and promotes restful sleep. The above bedroom images feature lights from Tala that offer Dim-to-Warm technology that allows you to set the lighting according to your desired colour temperature and dimming levels.

Maintaining a consistent colour temperature throughout a space is crucial for creating a thoughtfully designed environment. Mixing different colour temperatures can make an area feel uncoordinated and detract from the overall aesthetic. To avoid a disjointed appearance, ensure that your luminaires emit a harmonious colour temperature. This design choice guarantees a cohesive and seamless look, enhancing both the intended mood and functionality of every room.

LightForm Projects

Our custom lighting scheme for the feature wall at Toronto's Gusto 501, envisioned by Partisans Architecture, emits a to evoke the ambiance of flickering candles (*approximately).

The Shearer Design office in Calgary maintains a consistent 3,000K colour temperature throughout the space, creating a cohesive and intentional ambiance, ideal for a comfortable and creative workspace.

Need assistance with your lighting scheme? Get in touch, and we'll help create a bespoke lighting plan tailored to your specific needs.