All materials conduct heat. You can warm up your place to a comfortable temperature, but as long as the temperature outside is lower, your home will get colder. The flow of the heat from warmer to colder place is practically unstoppable, no matter how high-quality insulating materials you can find.

To compensate for the loss, we need to supply energy at a constant rate. This power is the power of a heater that this calculator will help you to compute.

To use the heat loss calculator and to find the power of the heater you need to give the dimensions of your room, specify on which floor it is and what type of insulation the walls have. If you are unsure which insulation type to choose, go for the worse insulation. It's safer to be pessimistic. Finally, you should also specify how many external walls are there. In the advanced mode, you can also include the number of windows and doors. With this information, we can compute the heat loss ( in watts divided by the temperature difference). Knowing the heat loss, we can estimate the power of a heater.

The last bit of the information needed is the difference of temperatures between inside (internal temperature) and outside (ambient temperature). The internal temperature depends on your comfort. The ambient temperature should be the minimum temperature occurring in your region.