Most lighting that looks wrong in a room is not the wrong design. It is the right design at the wrong size, hung at the wrong height. Both are avoidable with a tape measure and about ten minutes.
Diameter, for a room
The oldest rule in the trade still works. Take the length and the width of the room in feet, add them together, and the result in inches is a sensible diameter for a central fixture. A room 12 by 14 feet wants something around 26 inches across, or roughly 66 centimetres.
Treat that as a centre point, not a law. Go under it if the ceiling is low or the room is busy. Go over it if the ceiling is high, the room is sparse, or you want the fixture to be the thing people notice, which in a hallway or an entrance is usually the correct instinct.
Diameter, for a table
Over a dining table the room stops mattering and the table takes over. Aim for a fixture between one half and two thirds of the table's width. A 100 centimetre round table takes a 50 to 65 centimetre fixture. Wider than two thirds and people knock their heads standing up; narrower than a half and the piece looks stranded.
For a long rectangular table, a single round fixture rarely works. Either use a linear piece running along the table's axis, or hang two or three smaller pendants in a row, spaced evenly and set in from the ends by about a third of the gap between them.
Height, which matters more than diameter
Getting the drop wrong ruins a correctly sized fixture, and it is the more common error.
- Over a dining table: 75 to 90 centimetres, about 30 to 36 inches, from the tabletop to the bottom of the fixture. Lower for an intimate room, higher for a tall ceiling. The test is whether two people can see each other across the table.
- Over a kitchen island: the same range, measured from the worktop. Err lower here than you would over a dining table, because an island is worked at rather than sat at.
- In an open room or hallway: leave at least 210 centimetres, about 7 feet, of clear headroom under the lowest point. This is a floor to fixture measurement and it is not negotiable in a walkway.
- In a stairwell or double height space: the bottom of the fixture should sit above the highest point anyone stands, and the piece should be visible from both floors. Hang it so it reads from the upstairs landing, not just from the hall.
- Add for ceiling height: the usual adjustment is roughly 7 centimetres of extra drop for every 30 centimetres of ceiling above the standard 240.
Wall lights
Sconces flanking a mirror belong at eye level, around 150 to 165 centimetres from the floor to the centre of the light, and about 90 centimetres apart. Higher than eye level and they cast shadows downward across a face, which is the opposite of what a bathroom or dressing mirror needs.
In a corridor, space sconces 240 to 300 centimetres apart and hang them at about 150 centimetres. Fewer and brighter reads as a mistake; more and dimmer reads as architecture.
Bedside
The bottom of a bedside pendant or the shade of a table lamp should sit at roughly the height of your shoulder when you are sitting up in bed, around 50 to 60 centimetres above the mattress. If you can see the bulb from the pillow, it is too high.
The measurement people forget
Before ordering anything suspended, check the total drop the fixture can achieve and the ceiling height you actually have, including any slope. Many pendants ship with a fixed cord or rod length that can be shortened but not extended. Shortening is a five minute job for an electrician. Extending is a new part and a delay of weeks.
If a room is unusual, and plenty are, send us the dimensions and a photograph before you order. We would rather talk you into a different piece than sell you the wrong one.