Performance 2 project - Analysis of the interactions between the Humidity-based DCV systems and IAQ in homes 15 years after their construction

The Performance 2 project (2020-2024) is a French national research project that aims to evaluate the long-term performance and durability of Humidity-based Demand Controlled Ventilation (DCV) systems installed in two multi-family social housing buildings, located in Paris and Villeurbanne, France. This study investigates the interaction between the ventilation systems and the Indoor Air Quality (IAQ) 15 years after construction.  Continuous measurements over a two-year period were conducted on the Air Terminal Devices (ATDs) of the ventilation system functioning and the IAQ (CO2, Relative Humidity, and for Paris, Particulate Matters – PM2.5, Volatile Organic Compounds - VOC); with the sensors located close to the ATDs. Additional monitors measuring all the IAQ parameters plus Formaldehyde were placed in dry rooms for two separate winter IAQ campaigns. Occupants interviews were used to assess occupants’ behaviour over that two separate two weekly periods. This study has been carried out on 18 existing dwellings (13 in Paris and 5 in Villeurbanne, France) using data collected from November 2021 to December 2023 in Paris and from June 2022 to May 2023 in Villeurbanne.  
This analysis provides insights into the dynamics of pollutant concentrations, considering both standard reference values and temporal trends (dynamics). Focus was given to PM2.5, with findings revealing significant PM2.5 concentrations primarily in dwellings occupied by smokers. VOC concentrations varied among dwellings, with one particular case due to an under-ventilation situation (no source of humidity detected therefore the ventilation system provides always low airflow) leading to elevated levels, however most of the cases show consistent levels due to a daily use of perfumed candles, air freshener and incense. CO2 levels were generally low, however certain rooms exhibited higher concentrations attributed to under-ventilation in Villeurbanne and high occupancy in Paris.