To quantify the thermal comfort achieved in an office building placed in Madrid and considering climatic variations, building designs, behaviour of inhabitants and the operation of the conditioning systems, two experimental campaigns have been carried out during the summer and the wintertime. Depending on the season of the year different temperature profiles have been obtained as a consequence of meteorological variables and inhabitant concerns. Energy balance between indoors and outdoors indicate the thermal oscillation as well as the thermal deviation from the comfort bands. To analyze the daily evolution two typical days have been calculated by the Hall methodology. The quantification of thermal sensation of the occupants has been calculated by the PMV/PPD methodology. This evaluation shows low percentages of people dissatisfied with the indoor environments and low energy demands achieved inside the offices. (C) 2014 Elsevier B.V. All rights reserved.