Emitting panels can obviously be placed in the walls with the same success as in ceilings or in the floors. Since the walls are usually plastered, the wall heating panels are more similar in the device to ceiling than underground. For the most part, they consist of copper pipes made into a layer of plaster, or from steel pipes, made into concrete, then covered with a layer of plaster. Due to the same design of ceiling and vertical heating panels, the permissible maximum – their temperature is almost the same.
In cases where the heating panels are covered in the outer walls and especially into the window sill walls, they should be insulated most effectively from the outer side in order to avoid significant heat loss. If the panels are placed in the internal walls or in the partitions, this deficiency is eliminated due to the heat transfer of the other side of the panel into the adjacent room. With this arrangement of the panels, however, it becomes impossible to rearrange the partitions, which is an inconvenience for buildings in which it may be necessary to change the purpose and equipment of individual premises.
In France, such vertical panels are rarely used, only in cases where it is required to counteract the cold radiation of windows heating walls. It is preferable to put heating panels for this purpose, if possible, before the windows, either in the ceiling or in the floor, in order to avoid heat loss of the thermal conductivity of the external walls.
Such vertical heating surfaces are also used in cases where the surface of the ceiling or floor is insufficient to ensure normal heating of especially cold rooms due to limiting the temperature of heating surfaces for physiological reasons.