Calculating The Heat Output You Require

To produce a comfortable room temperature of around 21º/22º Celsius (70º Fahrenheit), when the outside temperature is 0º, you will need about 1kW of heat for every 14 cubic metres of space. 1kW is the equivalent of approximately 1 bar of an electric fire.

The following formula and example will give you a reasonable guide to the heat output you are likely to need. To establish the cubic capacity of the room, measure the length by the width by the height, for example a room that is in the region of 6.5 metres. (21ft. 6") x 4.5 metres. (15ft.) x 2.4 metres high (8ft.) will require a stove of about 5kW output to adequately heat its 70.2 cubic metres.

Therefore L x W x H divided by 14 = kWph.

This gives an approximate output for use as an initial guide in selecting an appliance based on an outside temperature of -1°C. However we strongly recommend that a site survey is undertaken by an experienced stove installer before you make your purchase.

Appliances are selected with an output slightly greater than the requirement to allow for more rapid heating in colder weather. Figures are based on approximate heating requirements shown in the HETAS® Guide to Solid Fuel Products and Services.