An average house in a Nordic climate with standard insulation and ceiling heights between 2.40-2.50 m requires around 70-75 W per square metre of floor area. To calculate the required heating power for other ceiling heights, base the wattage on 30 W per cubic metre of volume, plus 20% if badly insulated in order to work out the exact output required. It can in some cases be an advantage to have a gross power need of 100W/m2 for under floor heating. This calculation is based on houses in the Nordic climate and can also vary according to the standard of the house. For more information about the power requirements for houses in other climatic regions, contact your local electrical contractor or energy advisory service.