IAQ and ventilation measurements at the “ZEB Laboratory” office building in Norway

This study aims to assess indoor environmental quality (IEQ) within a Zero Emission Building (ZEB) office in Norway, focusing on occupant impact (CO 2 , temperature, humidity) and materials/substances influence (formaldehyde, particulate matter (PM 2.5 ), total volatile organic compounds (TVOC)). It presents a detailed data collection spanning 14 months from March 30 th , 2022, to June 1 st , 2023. Occupancy varied significantly, affecting measured indoor air quality (IAQ) parameters, with the lowest temperatures recorded on the second floor and specific areas like the canteen experiencing temperature drops during low usage times. Relative humidity levels remained over 20% in winter despite the building's low occupancy, a notable aspect given Norway's dry winters. PM 2.5 levels stayed below World Health Organization (WHO) guidelines, indicating effective pollution management. The study also evaluates the impact of reducing the ventilation rates on IAQ, noting no significant IAQ compromise. An analysis correlating IAQ measurements with building occupants' satisfaction post-intervention revealed that temperature is the most significant factor affecting satisfaction levels, excluding acoustic satisfaction. Occupants generally reported satisfaction with the indoor environmental quality (IEQ), with specific dissatisfaction tied to thermal environment and IAQ, suggesting the importance of temperature control in occupant perception. This research not only provides valuable insights into IEQ management in Zero Energy and Zero Emission office buildings but also emphasizes the critical role of indoor temperature and the potential of wooden structures to stabilize humidity levels, contributing to occupant comfort and satisfaction. • Temperature, RH, CO 2 , formaldehyde and TVOC measured for 1.5 years in ZEB office. • Evaluates impacts of reducing airflow rates on IEQ, noting insignificant IAQ effect. • An analysis correlating IAQ measurements with building occupants' satisfaction. • Role of temperature and wooden structures on RH, and occupant satisfaction.