Gravity ventilation is a form of natural ventilation. It can be used to dehumidify indoor bathrooms and is mainly found in existing buildings today. However, new buildings also have this type of ventilation for dehumidifying interior bathrooms. Since gravity ventilation is controversial, but little concrete information is available, a better information situation is to be created. To this end, an online survey is being carried out among housing associations. This should lead to a gain in knowledge about the spread, the technology used and user satisfaction with gravity ventilation in interior bathrooms. As the response rate to the online survey was low, the survey was revised and shortened. It will be distributed a second time via the wbg newsletter (Wohnbaugenossenschaften Schweiz) and also sent separately by e-mail to 15 housing cooperatives. As there is no response to the second survey, an Excel sheet is created to query the ventilation systems generally used, which is also sent directly to various housing cooperatives. 10 housing cooperatives responded to this specific request. A general overview of the ventilation systems in the residential buildings shows that the majority of apartments are ventilated via window ventilation. The main ventilation systems for bathrooms and toilets are window ventilation or exhaust fans. Four cooperatives have gravity ventilation for bathrooms/toilets. This corresponds to 7 % of the total number of apartments surveyed. It has proven very difficult to obtain information about gravity ventilation. In summary, three housing cooperatives and one building physics office are positive about gravity ventilation within the scope of this project. Unfortunately, no information could be obtained from the fourth. The housing cooperatives and the building physics office report that gravity ventilation does not cause more mold problems than other ventilation systems. In the event of renovation, gravity ventilation is not necessarily replaced with another type of ventilation. In 2022/2023, new buildings will even be constructed with gravity ventilation. There is no negative feedback on gravity ventilation. It should be noted that the findings only apply to the cooperatives involved here