Ventilation performance and indoor air pollutants diagnosis in 21 French low energy homes

Ventilation’s historical goal has been to ensure sufficient air change rates in buildings from a hygienic point of view. Regarding its potential impact on energy consumption, ventilation is being reconsidered today. An important challenge for low energy buildings lies in the need to master airflows through the building envelope. Data collected from controls in 1287 recent dwellings shows us that 68 % of the dwellings don't respect the French airing regulation. In this context, actors in the building’s sector are reflecting on the risk of an unhealthy indoor air environment in this generation of high performance airtight dwellings.
“VIA-Qualité” project proposes to develop quality management (QM) approaches (ISO 9001) with the goal of increasing both on-site ventilation and indoor air quality in low energy houses.
The first step in this project consists in a campaign on 21 low-energy houses. First, we carried out an aeraulic measurement campaign on every dwelling including visual survey, airflow or pressure at the air-vents, ventilation duct airleakage, and acoustics measurements. Then, we selected 10 dwellings to carry out an indoor air quality winter campaign. This campaign included outdoor and indoor measurements of temperature, relative humidity, carbon dioxide, chemical pollutants (VOC, aldehydes). Inhabitant habits and building influence were studied through a complementary questionnaire survey.
With this campaign, we were able to identify ventilation dysfunctions and to compare them with the national statistics on dwelling stock. The second part of the measurement campaign allowed us also to identify links between aeraulic diagnoses and indoor pollutant measurements.