A major increase of complaints has been observed by the occupants of buildings, concerning health symptoms and comfort. In this study, the occupants＇ experience of symptoms as well as the occupants＇ sensation of the environmental parameters were estimated in six office buildings, where the indoor air quality was investigated. It was found that the percentage of building related symptoms experienced by the occupants of the buildings was high and it was strongly related to human comfort and human sensation concerning the environmental conditions. The human response to the environmental conditions showed that none of the parameters was judged as being unacceptable overall, which indicates that the number of symptoms observed in each building cannot be attributed to one cause but to the contribution of various environmental parameters. Moreover, it was found that the increase of energy consumption was associated with the increase of health symptoms for these buildings.