What is Mechanical Extract Ventilation (MEV)
Mechanical Extract Ventilation (MEV) systems provide continuous ventilation.
Centralised mechanical extract systems (c-MEV) also known as a Multipoint and Central Extract System draw moisture-laden air from multiple wet rooms of a property, Essentially the concept is to provide simultaneous, low level extraction from kitchens, bathrooms, shower rooms, utility rooms and toilets to a central extract fan typically located in a loft space or hallway cupboard via a system of ductwork and grilles to control humidity levels.. The extracted air is then normally discharged to outside via a single duct and grille/cowl.
Decentralised mechanical extract fan (d-MEV) also known as a continious running fan is perfect for single applications such as bathroom, kitchens or utility rooms if a (c-MEV) is not suitable
As this type of system has to work 24 hours a day, 7 days a week, 365 days a year, low noise levels and reliability are critical.
Our MEV systems are cost-effective and offer many benefits to home-owners:
-
Elimination of condensation dampness
-
Healthier living environment
-
Removal of musty odours
-
Low running costs and low-energy operation
-
Easy installation and low maintenance
MEV Suitable Applications:
-
Ideal apartment ventilation solution where there is possibly only one external wall.
-
Homes with more than one wet room.
Building Control System 3
Building Regulation Part F - System 3 covers continuous mechanical extract ventilation (MEV). This can be either a whole house centralised MEV system, or localised decentralised MEV fan.
Current Building regulation requires such systems be designed to provide background extraction at a rate equating to approximately 0.3 to 0.5 air changes per hour or individual room rates of 13 kitchen,and 8l/s for bathrooms (whatever higher is used) with the ability to boost by approx 25% for times when increased ventilation is required e.g. during cooking.
Replacement air is normally able to be provided via structural air leakage with older buildings above 5ma@50Pa or if the home is built to good airtight standards with background ventilation openings like trickle vents and wall vent having a minimum equivalent area of 2500 mm2 should be fitted in each room, except wet rooms, from which air is extracted
Always refer to your local building contro regulations as this information can change.
