Vaasa Vocational College in Finland is a secondary education centre built/refurbished in 2013, and there are 17 different vocational qualifications and 34-degree programs. School buildings are characterised by a high degree of occupancy of the premises, so in addition to standard airflow ventilation systems, appropriate ventilation systems were designed to serve the building. The long daily operating hours of the Vocational College favoured the design of adequate ventilation. In addition to everyday use, the annual utilisation rate is high as the school is exceptionally closed for only three weeks in summer.
The user satisfaction in the school building can be high, but also it can be overshadowed by the temperature problems in the individual rooms, partly due to misuse of the premises and partly due to malfunctions in the heating system. Problems with indoor air quality could be attributed to the ventilation system because overheated air can be perceived as clogged and, consequently, the ventilation might be insufficient. In general, the excellent quality of air in the school areas where ventilation can be achieved and proved by the measurement results.
Master Thesis by Juha Pasila, 2013. Seinäjoki University of Applied Sciences, Finland. The thesis is in the Finnish language.
The study aimed to research indoor air quality problems in problematic spaces. The thesis investigated the energy savings of demand-controlled ventilation system compared to a standard ventilation system with cooling. Energy-saving calculations were restricted to cover the consumption of electrical and warming energy. The energy savings of demand-controlled ventilation system were calculated by using building automation trend specifications collected during six months. The thesis also inspected the microclimate of rooms sustained by demand-controlled ventilation. A questionnaire study was used to evaluate air quality and room air temperature. The questionnaire study included various methods to assess the air quality and room air temperature. The repayment period of the demand-controlled ventilation system was evaluated in addition to annual energy saving calculations. The demand-controlled ventilation system decreased the heating expenses and consumption up to 46,8 % in heating energy and up to 72,8 % in electrical energy. The repayment time for demand-controlled ventilation system was seven years using moderate energy escalation calculations. Note: The thesis was made for one air handling unit in the building S Sähkötalo (Electric house).