Ventilation of buildings is a good way of preventing transmission of some virus in aerosolized form as the SARS-CoV-2. In many buildings, prevention strategies as window opening and sealing door have to be considered with a multizone approach. Approach. We modelled a residence equipped with a exhaust-only ventilation system where a family is isolating in a pandemic context, with one infected person. We modelled and analysed the impact of opening the window and sealing the door in the quarantine room on exposures. We tested several window- and door-opening strategies. Results. We illustrate the importance of moving from a single zone approach to a multizone approach for quantifying ventilation and airing impacts in multizone buildings as residences in order to prevent epidemics of viruses like SARS-CoV-2.