Energy consumption, thermal comfort and indoor air quality in schools

School buildings in Flanders are quite old. They cause concern not only about energy efficiency but also about thermal comfort, indoor air quality, speech intelligibility and visual comfort. To evaluate the correctness of the concerns, energy consumption was monitored in 18 schools, while in each of them a classroom was selected for detailed measurements on comfort and indoor air quality. The results justify the concern. Energy consumption per pupil varies significantly, from low to really high. The reasons for that are quite clear: poor heating system control, hardly a nighttime and weekend setback, un-insulated buildings. CO2 in almost all classrooms peaks at values far beyond 1500 ppm, which underlines that the air quality is a problem. Thermal and visual comfort anyhow did not pose many problems. The research resulted in a series of design guidelines for school buildings with low energy consumption, good comfort and excellent indoor air quality.