De-central continuous extract ventilation (dMEV) is a form of whole house ventilation, which is based on extract fans in wet rooms and the kitchen, continuously extracting air in trickle speed. The fans can be boosted when excess humidity needs to be expelled.
When the building is relatively airtight (q50 is less than 5 m3/(hr m2) at 50Pa), trickle vents need to be installed in all habitable rooms. Thus an airflow of fresh air is established throughout the dwelling.
Unlike MEV systems with a central extract fan and ducts throughout the building, dMEV is ductless. However compared to MVHR, dMEV has got no heat recovery.
We would see dMEV as the second best option of ventilation after MVHR systems. Modern dMEV units, such as the Unity CV3 are very versatile and can have as much or less user interaction as needed. It can be locked and securely monitored and adjusted.
Unity CV3 is ideal for private landlords, housing associations and local authorities as it combines low capital and life-time cost with a reliable solution that fulfils their legal obligation to provide healthy living conditions. The unit can be locked in its settings and if users e.g. switch off the ventilation, a message can be sent to the maintenance partner, showing the status and switch off periods of each system. On top of this the system is one of the quietest on the market.