This refers to the simultaneous connection of multiple fireplaces to a common exhaust system. The devices can be operated independently of each other. This happens more often in multi-storey apartment blocks or in single-family homes with several fireplaces on different floors.
In order to comply with all requirements and approvals, a few points must be considered before installation and the relevant diameter of the exhaust gas system should be calculated. For example, the devices must not obstruct each other or push the exhaust gases of the lower system to the next higher storey. A mixed allocation, i.e. different fuels for the individual fireplaces is permitted as long as the requirements according to DIN standards are met. The fireplaces that can be used with collective chimneys are marked with a note of permit. In principle, every collective chimney should be scrutinized and clarified with the chimney sweep.