What size heater do you need for a small room?
A reliable starting point for New Zealand homes is 100 watts per square metre of floor space, assuming a standard ceiling height of 2.4 metres.
- Up to 10 square metres (small bedroom, study, or bathroom): 1,000 to 1,200 watts
- 10 to 15 square metres (standard bedroom or large study): 1,200 to 1,500 watts
- 15 to 20 square metres (larger bedroom or small living area): 1,500 to 2,000 watts
These figures assume reasonable insulation. Rooms with single-glazed windows, no ceiling insulation, or draughty doors and floors lose heat faster and need more wattage. Step up to the next wattage range if your room fits that description. Rooms above standard 2.4 metre ceiling height also need additional output.
Which heater warms a small room fastest?
Fan heaters warm a small room faster than any other portable electric heater type. They draw cool air across a heated element and blow warm air directly into the room, raising the temperature in minutes. Ceramic fan heaters heat up faster than standard coil element models, but the fan noise makes them less suitable for sleeping environments.
Sizing up right:
It is better to buy slightly more wattage than you think you need and run it on a lower thermostat setting than to undersize and run a heater at full output continuously. Oversizing saves energy in the long run.