Abstract Localized HVAC systems with the task-ambient conditioning concept represent a promising option towards energy-saving in buildings. The design of such systems needs to involve evaluation of the local thermal comfort that corresponds to different body segments. In this work, an experimental technique using a thermal manikin was developed to determine the optimum configuration(s) among different variants of localized floor-heating systems for a single seated person. The experimented variants had different geometries or surface areas. Their surface temperatures were experimentally found subject to thermal comfort criteria and under a lowered ambient temperature. In the experiments, the thermal manikin was regulated in a dynamic mode using a model of human thermoregulation and was employed to evaluate the fulfillment of the thermal comfort criteria. The experimental setup was constructed to simulate a task area in a large hall space that may be feasible for shopping mall's application. The energy consumption of the floor-heating systems was measured to evaluate the energy performance of the different system variants. The results showed that in large hall space under lowered ambient temperature around 18 °C, a heated floor with certain geometries and a surface area of nearly 1 m 2 could fulfill the comfort criteria and represented the optimum configuration.