By roomAdd the room’s length and width in metres and multiply by eight. The answer is the fitting’s diameter in centimetres — a 4 × 5 m room wants about 75 cm.
- The rule
- Add the room’s length and width in metres and multiply by eight. The answer is the fitting’s diameter in centimetres — a 4 × 5 m room wants about 75 cm.
- Height under the ceiling
- Allow 6 to 7.5 cm of fitting for every 30 cm of ceiling. Under a standard 2.7 m ceiling that is an overall height of 57 to 69 cm.
- The lowest point
- Anywhere people walk, the lowest point stays at least 2.1 m above the floor. Over a dining table it is the opposite — 75 to 85 cm above the top, because nobody walks there.
