Abstract: Allocation of heating costs in an apartment building having a central heating plant common to a number of apartments in dependency of the heat comfort really enjoyed by the consumers concerned by basing said allocation upon a representative instantaneous average air temperature in the apartment in question, said temperature being determined by electric measurement with means highly sensitive to temperature changes and placed at one or more suitable points in the apartment concerned, said temperature value being also simultaneously rated with respect to the room surface represented, the obtained average temperature being thereafter integrated by passing the measured value via a converter to an electric integrating device, the output value of which determines in conjunction with the apartment surface the part each individual consumer has in the total heating costs for the apartment building.