The purpose of the study is to determine if the thermal comfort in a kindergarten built to the Passive House standard shows improvements in thermal comfort levels and energy consumption when compared to one built to contemporary Austrian building regulations. Two case study kindergartens in Vienna were used. The kindergartens have similar occupancy, architectural programme, overall building volume, and building services. Indoor environmental parameters, such as temperature and relative humidity, were measured in 20 rooms in the two kindergartens for a six month observation period. The rooms are divided into two categories:
primary use spaces (classrooms), and secondary use spaces (kitchens, bathrooms, staff rooms, atria, and circulation spaces). Five classrooms per kindergarten were studied. Carbon dioxide levels were also measured to determine indoor air quality, and questionnaires distributed to obtain the subjective comfort levels of occupants. Measured data is compared to the Passive Houses design criteria, the Austrian standards, and to the questionnaire responses. It was found that both kindergartens experience warmer temperatures overall than the design parameters, and that the Passive House Kindergarten, (PHKG), has lower humidity levels in the winter months.
The majority of questionnaire responses from the PHKG indicated that occupants still found the rooms to be cold in winter, but the Standard Kindergarten, (SKG), users found the rooms to be too warm. Measured indoor air quality (IAQ) in the PHKG was better in the winter months than in the SKG according to both the measured carbon dioxide levels and questionnaire responses. However, IAQ in both kindergartens improved significantly in the warmer months of April and May when the occupants began to open windows for longer daily durations showing similar indoor concentrations to outdoor carbon dioxide concentrations. Energy consumption for heating was lower for the PHKG; with slightly higher electricity consumption in the PHKG due to the additional electricity required for the ventilation system and solar panel circulation pumps.
The temperature set points of both kindergartens should be adjusted and maintained in relation to the expectations of the occupants and it would be recommendable to adjust ventilation controls to carbon dioxide levels.