Reliability of Ventilation System Inspection for Dwellings: Comparisons of Measurements and Controls Protocols Tested during in-Situ Campaigns of the Promevent Project

In France, various controls and measurements are performed in order to assess the performance of ventilation system, such as visual controls, airflow and pressure measurements at terminal devices and ductwork airleakage measurement. Those tests are performed according to several protocols, which might conduct to different results with different uncertainties. In this context, 8 French organisms participate to the PROMEVENT program, which is supported by the French Ministry for Construction and ADEME (French Agency for Energy). It aims to make the practices more uniform and to improve ventilation systems inspection protocols for both single-family houses and multi-family dwellings. In order to test the reliability of those protocols, various measurements have been performed on 2 multi-family dwellings with humidity demand controlled ventilation system and 10 single-family houses with balanced ventilation with heat recovery systems. For airflow and pressure measurements at terminal devices, tests have been performed by different operators, with different types of material, on different types of terminal devices, on repeatability conditions and with different applications of the protocol. The same method has been applied for ductwork airleakage measurements, with also different ductwork preparation and different parts of the ductwork tested. The analysis of these different measurements points out the weaknesses of the protocols and/or the minimum specifications the instruments should achieve to assure reliable results. In particular, for airflow measurement at terminal devices, the position of the material around the terminal could induce very important errors if the material is not centered or not airtight with the wall around the terminal. Moreover, the type of material used may induce uncertainties due to the technology (not all technologies might be used with all types of terminal) and due to the material it-self (important impact of the correction with calibration data). For ductwork airleakage measurements, important differences of the results have been noticed with different obstructions of the ductwork at terminal devices. Results could also be different between a measurement performed in one time (one section) or in two times (the same section divided in two sections). Therefore, all the tests performed during these campaigns confirm the need for a unique and more reliable protocol. Those results are consistent with the results of tests performed during the laboratory campaign of the program. A new protocol will be proposed and tested during the next phases of the PROMEVENT project, including uncertainties evaluation for each type of measurement.