Four lamps beat one sofa

Walk into an expensive room and an ordinary one and the difference registers before you have identified a single object. Most of that first impression is light: how many sources there are, how high they sit, what colour they are and what they do to the colours of everything else. It is also the cheapest variable in the room and the one almost nobody touches.

The overhead problem

A single ceiling fixture in the middle of a room produces light from directly above, which casts shadows downward into eye sockets, flattens every surface it hits directly and leaves the corners dark. It is the lighting scheme of an office corridor, and it is the default in most homes because it is what the wiring provides.

The fix is not a better ceiling fixture. It is to stop using the ceiling fixture in the evening, and to replace it with several sources at or below eye level. Four is the number where a room stops looking lit and starts looking inhabited: two lamps at table height, one at floor height throwing upward, and one wherever you actually read.

The three numbers on a bulb box

• Colour temperature in kelvin. 2,700 is warm and correct for an evening room. 3,000 is acceptable. 4,000 is an office and 5,000 is a hospital. Every bulb in one room should be the same figure, and mixing them is the most common and most visible lighting error in the world.
• Colour rendering index, CRI. It measures how accurately a light source shows colour against daylight. Below 80, wood goes grey, skin goes sallow and fabric colours collapse. Above 90 everything looks like itself. The difference in price is small and the difference in effect is large.
• Lumens, which is actual brightness. A traditional 60 watt bulb was about 800 lumens. Four sources of 400 lumens each produce a better lit room than one of 1,600.

One bright light makes a room you can see. Four soft ones make a room you want to sit in.

Where the sources go

Layer by height. Something low, a floor lamp or an uplight behind a chair, which lifts the ceiling and gives the room volume. Something at table height, which is where a room gets its intimacy. Something task focused, aimed at whatever you actually do. And something that lights a surface rather than a space: a picture, a shelf, a plant, which is what stops the walls reading as a boundary.

The trick everybody in the trade uses and nobody mentions is to light the corners. A dark corner shrinks a room, a lit one extends it, and a single small lamp on the floor behind a piece of furniture does more for the perceived size of a room than rearranging everything in it.

Dimmers, and the one thing to check

Every source in an evening room should dim. The caveat is that many LED bulbs dim badly, flickering or buzzing or refusing below fifty per cent, and the incompatibility is between the bulb driver and the dimmer type rather than a fault in either. Buy dimmable bulbs from one maker, in one colour temperature, and test one before buying eight.

Better still, use bulbs that warm as they dim, which imitate the behaviour of the incandescent lamps that trained everybody expectations. They cost a little more and they are the single closest thing to a shortcut in this entire subject.

What this replaces

A budget of 400 spent on four good lamps with high CRI bulbs at 2,700 kelvin will change a room more than 4,000 spent on a sofa. That is not an argument against the sofa. It is an argument about order of operations, and the order is almost always wrong.

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