Hybrid Natural Ventilation

                                          Roof Terminals

Gilberts MFS-V offer a further innovation in hybrid natural ventilation.  Our standard MFS solution allows hybrid ventilation to be provided in a typical classroom using the exterior wall façade. For areas where a side wall is not available however our hybrid MFS-V offers the perfect partnering solution.

The MFS-V provides a roof top hybrid natural ventilation solution. Perfect for internal zones such as auditoriums or other areas where sidewall solutions may be problematic such as sports halls.

The solution is designed to comply with the design guidance for PBSP prescribed in Department of Education’s Guidance on Ventilation, thermal comfort and indoor air quality in schools and the Latest BB93 Department for Education Acoustic Performance Standards for schools

A penthouse turret on the roof builds onto a vertical sleeve which terminates with an air distribution plenum inside the space. The terminal uses natural air buoyancy with low power fan assistance to deliver a steady supply of fresh air from whilst allowing it to blend controlled amounts of mixed extract air for heat recovery.

So MFS-V is a dynamic hybrid that includes an ultra low power fan assistance feature able to energise in poor air movement conditions to ensure adequate ventilation at all times. The fan is there to provide only occasional support ensuring that the terminal operates at all times to provide design heat recovery and ventilation requirements.

And it is truly energy efficient. With a design consumption of just 34kw per year per classroom Mistrale MFS-V enjoys low annual running costs yet guarantees full operational ventilation and cooling efficiency at all times.

Unlike other designs, Mistrale MFS is a stand alone system providing adequate ventilation and cooling without the need for supportive systems such as opening windows although it can still be integrated with other heating, cooling or ventilation strategy if required.


  • Energy efficient ventilation solution
  • Compliant with DoE guidance on ventilation
  • Accurate air and temperature control with free cooling and heat recovery
  • Full summer evacuation mode with fan boost to meet all BB101 and PBSP overheat requirements
  • Includes CO2 override to meet current D of E guidelines
  • Operator overrides with easily adjustable set points
  • Clear indication of control strategy for users/occupants
  • Low noise operation to meet current D of E guidelines (BB93)
  • No ductwork requirement and maintenance free
Beneath the roof terminal a duct sleeve penetrates through the roof and terminates in the occupied space venting either through an air grille
 (numerous design choices) or a plenum fitted with multiple air grilles. Roof depths of up to 1670mm can be accommodated as standard
Available in 2 sizes (900 and 1400mm) access to the fans and dampers are available in the event of any adjustment or maintenance 

For more product details see page 27 in our MFS Fusion brochure 

Your window on Natural Ventilation

Passive Natural Ventilation

Pure natural

Hybrid Natural Ventilation

Natural Ventilation with fan power assistance

Hybrid Roof Terminals

Natural roof vent with fan power assistance

Hybrid Heat Recovery

Natural Ventilation with heat recovery

Gilberts Mistrale Natural Ventilation Solutions are design led technologies that incorporate patented features which position them at the leading edge of modern natural ventilation design. Suitable for both stack effect and wind driven systems Mistrale comprises of all of the key the components you will need to design a robust, efficient and extremely effective natural ventilation system.

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