BTU is the acronym for British Thermal Unit, which is the standard British unit of energy. To get into the technicalities of it,
1 BTU is equal to the amount of heat required to raise the temperature of one pound of liquid water by 1 degree Fahrenheit at its maximum density, which occurs at a temperature of 39.1 degrees Fahrenheit.
When it comes to choosing your new radiators, the higher the BTU then the bigger the room that your radiator will be able to heat.
There are various “radiator BTU calculators” available on-line, but you can follow a fairly simply rule, for regular homes with rooms of average height (2.5m) – for every square meter you want to heat in a room, you will need about 100 BTU. Here are few examples,
- Small room – 12 square meters (3m x 4m) – at least 1200 BTU
- Medium room – 20 square meters (4m x 5m) - at least 2000 BTU
- Large room – 30 square meters (5m x 6m) – at least 3600 BTU
- Extra Large Room -42 square meter (6m x 7m) – at least 4200 BTU
If you have high ceilings, Lot’s of outside walls, large windows or single glazed windows, you will want to add more.
1 Btu is equal to approximately 251.9 calories or 1055 joules.
