Bedroom light and your sleep

The bedroom is the one room in the house where the goal of light is to prepare for darkness. Most bedrooms in Vietnam are lit in complete opposition to that principle.

Light is a signal, not just a tool

The body releases melatonin — the sleep hormone — as the surrounding light dims and warms. A bedroom ceiling fitted with bright white light right up until you flip the switch tells the brain "it's still daytime," and sleep comes more slowly. Years of circadian research all point one way: the evening needs warm light below 2700K, low in intensity, and above all low in position.

The principle: "the later the night, the lower the light"

IDA's bedroom designs usually have three levels: indirect ceiling light for tidying and changing; pendants or wall lights on either side of the bed for reading; and low floor-level light — washing the bed base and cabinet feet — for the half hour before sleep and for waking in the night. Night light placed below eye level barely stirs the circadian rhythm, whereas switching on the ceiling light at 2am is the equivalent of a cup of coffee.

A good bedroom is not the darkest one — it is where the light knows to retreat in step with your body.

The details usually forgotten

The bedside reading light should be adjustable, aimed precisely at the page and not spilling onto the other half of the bed. The bedside switch must control the whole room — no one wants to turn the light off at the door and grope back to bed in the dark. Curtains and the light gap from the corridor are part of the lighting design too: a 5mm strip of light under the door is enough to ruin an otherwise well-designed bedroom.

Bedroom lighting is the cheapest item in the house yet directly affects your health every day. The investment here lies not in the price of the fixtures, but in the correctness of the layout.