Mechanical Extract Ventilation

What is Mechanical Extract Ventilation (MEV)

MEV system

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.

A D-MEV – decentralised mechanical extract fan, is also known as a continuous running fan is perfect for extracting from single applications such as bathrooms, kitchens and utility rooms.

Decentralised mechanical extract fan (d-MEV) also known as a continuous running fan is perfect for single applications such as bathroom, kitchens or utility rooms if a (c-MEV) is not suitable.

This type of system works 24 hours a day, 7 days a week, 365 days a year, due this this they have low noise levels and are reliable.

Our MEV systems are cost-effective and offer many benefits to home-owners:

  • Elimination of dampness and condensation
  • Removal of musty odours
  • Healthier living environment
  • Low running costs and low-energy operation
  • Low maintenance
  • Easy installation

MEV Suitable Applications:

  • Ideal for applications such as apartments where there is possible only one external wall
  • Suitable for homes with more than one wet room.

Building Control System 3

Building Regulations 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 control regulations as this information can change.

MEV Solutions:

Vent Axia Sentinel Multivent 

Vent-Axia MEV

The Vent Axia Multivent Unit is one of our most popular Mechanical Extract Ventilation units (MEV). They are popular due to their high-quality constructions, reliability and controllability. The unit features 3 x 125mm extraction points on the sides and 1 x 125mm at the back of the unit.

Xpelair Xplus 2 EC - 92498AG

Xpelair MEV unit

Xpelair Xplus 2 EC unit has 3 selectable speeds with E/C motor. The Xpelair Xplus MEV unit is a top quality UK Manufactured unit providing a powerful extraction system and outstanding value for money with 6 extraction ports.