Joyacy — Residential decorative lighting: how room size | joyacy.com
Colour temperature is measured in kelvin: 1,800 K is candlelight, 2,700 K is the old incandescent, 4,000 K is neutral and 5,000–6,500 K is daylight.
The scale is practical because it is coarse: each 1,000 K step visibly changes how a white painted wall reads. That makes kelvin a design decision with immediate consequences, not a spec-sheet detail.
Living rooms and bedrooms sit at 2,700 K, the incandescent colour most people read as home. Halogen's 3,000 K is the crisp upper limit for relaxing spaces — beyond it, rooms start to read as workplaces.
On narrow screens, swipe or scroll the plate sideways.
Kitchens and vanities earn cooler light: 3,000–4,000 K over worktops, mirrors and wardrobes, paired with Ra 90+ so food, faces and fabric colours are judged accurately. The ambient light in the same room can stay warmer.
Daylight lamps at 5,000–6,500 K have their place in utility rooms and garages. In a lounge at night they read clinical, and against a 2,700 K lamp in the same sightline they read as a mistake.
Time of day argues for warm light in the evening: candle flame at 1,800 K is the historical night-time reference, and 2,700 K is its modern stand-in. Keep one kelvin per sightline — mixed temperatures do not average out, they clash.
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