Investigation of future ventilation flow rate requirements for dwellings in Belgium : from the application of FprEN16798-1:2016 to proposed robust rules

In the context of the PREVENT project, preparing a possiblerevision of the Belgian residential ventilation standard, the way of expressing ventilation requirements, among others in terms of ventilation flow rates, needs to be investigated. The aim of this paper is to propose and compare ways of expression of the ventilation requirements in terms of flow rates with respect to their robustness across dwellings. The application of the different methods proposed in the recently developed new draft standardFprEN 16798- 1:2016 has been compared for a series of Belgian dwelling configurations: method based on the perceived air quality, method using criteria for pollutant concentration and method based on pre-defined ventilation flow rates. The calculated flow rates varied significantly depending on the calculation method used. Based on these results, some rules to express the ventilation requirements in dwellings in Belgium are proposed. One should first consider the ventilation flow rates for normal use during occupied periods. This flow rate could be based on those for occupancy per person proposed in FprEN 16798-1:2016 for non-adapted persons, provided it is higher than those for emissions from building. The determination of the number of persons could be based on a minimum of one person per bedroom, at least one bedroom for two persons, and a number of persons in the living rooms based on the total number of persons in the bedrooms. Second, a minimum flow rate for unoccupied periods and a minimum flow rate for rooms without any IAQ sensor (in case of demand controlled ventilation and manually controlled ventilation) could be set based on the flow rate for the emissions from building materials. Finally, the design flow rate of the system at the building level could depend on the controlstrategy of the ventilation system (i.e. sensor and actuator location) with a minimum corresponding to the highest value for the total flow rates for occupied periods in the night zone (bedrooms and similar) and those in the day zone (living room and similar). The proposed rules could lead to more robust and efficient ventilation requirements for dwellings in the future in Belgium