Warm or Cool Light? A Practical Kelvin Guide

Colour temperature describes whether a light source appears warm, neutral, or cool. It is measured in Kelvin (K): a lower number looks warmer, while a higher number appears whiter and cooler.

The choice changes how materials, colours, and faces appear. A lamp should therefore be selected with the room it will illuminate.

Three useful ranges

• 2700K: warm, soft light suited to evenings, bedrooms, and relaxation areas.
• 3000K: still warm but cleaner; effective in living rooms, hallways, and many home kitchens.
• 4000K: neutral and clearer for work areas, mirrors, utility rooms, or details requiring accurate visibility.

Choose around the activity

A kitchen can combine warm general light with slightly more neutral task lighting beneath wall cabinets. In a bedroom, soft bedside light is usually more appropriate than a very cool ceiling source.

Near a mirror or wardrobe, choose lighting that represents colour naturally. Temperature is only part of the result; position and source quality matter just as much.

Do not mix temperatures without a reason

When a 2700K lamp and a 4000K lamp are visible together, the room can feel inconsistent. Establish one base temperature and change it only where a source has a specific function, such as task light.

Test with the actual materials

• View the timber sample and wall colour under the lamp being considered.
• Check it in the evening, when artificial light becomes dominant.
• Assess shadows on faces, worktops, and inside wardrobes.
• Use dimming where one room supports several activities.