Indoor Air Quality and Thermal Comfort, in Irish Retrofitted Energy Efficient Homes

Indoor air quality and thermal comfort was measured in 14 three-bedroom, semi-detached, cavity wall naturally-ventilated homes during the winter following an energy efficient retrofit. As part of the energy retrofit, homes received new windows and doors, an upgraded heating system, attic insulation, and wall vents, as well as pumped beaded wall insulation into three external walls. Temperature and relative humidity (RH), as well as concentrations of total volatile organic compounds (TVOCs), PM2.5, CO2, and CO were measured over a 24-hour period in the main living area and main bedroom of each home. Concentrations of NO2 and formaldehyde were measured in the living room only. Benzene, toluene, ethylbenzene, xylene, and NO2 were measured over a three week period and radon was monitored over three months.   
The average winter air change rate was 0.59 h-1. The average PM2.5 concentrations during the winter period were 18.5 µg/m3. The 24 hour average formaldehyde and TVOC concentrations were 19.4 ppb and 379.7 ppb respectively. The average 24 hour temperatures and humidity levels found in the living room and bedrooms in the retrofitted dwellings were 20.0 ºC and 19.1 ºC and 46.8 %RH and 50.4 %RH, respectively.