Ceiling heating in new and existing buildings

This paper presents a number of advantages (both practical and thermodynamic) of ceiling heating systems compared to under-floor heating. It is estimated that the heat flux from ceiling heating is approximately the same as under-floor heating: the larger exposed surface of the ceiling, and the lower thermal resistance between the water in the pipes and the ceiling surface, compensate for the lower convective heat flux from the ceiling. Using the same water temperature in the pipes, the total heat flux from ceiling heating will be similar to that of under-floor heating. If the convective heat transfer is increased by means of forced convection (e.g. by placing a ventilation supply diffuser in the ceiling, or a hanging circulation fan) then the useful heat output can be increased further, and no supplementary heating should be needed.