Dwelling Environmental Quality Index: An indicator of indoor environmental quality in residential buildings

Efforts to save energy may easily lead to the compromisation of indoor environmental conditions and vice-versa. This study suggests an indicator for indoor environmental quality classification, developed with the purpose of assisting households that are trying to save energy, to maintain optimum levels of indoor environmental quality during this effort. The “Dwelling Environmental Quality Index” (DEQI) is a comprehensive indoor environmental quality indicator, reported to occupants as an easily understood number (percentage). The DEQI is calculated for a thermal zone in which indoor air temperature, relative humidity and CO2 levels are monitored. It expresses in a single value the prevalent indoor environment quality category for the monitored period, based on the four indoor environment categories defined in standard EN 15251. Calculations for the DEQI rely on actual hourly measurements which may correspond to an entire-day, a week, a season or to a whole year, and as a result is capable of acting as a performance indicator for short-, medium- and long-term energy conservation measures implemented during the measured period.