Passive Natural Ventilation Solution

                                 MISTRALE 75 

The Mistrale 75 is a medium format natural ventilation solution that has been specifically designed to fit in to both curtain walls, brick or masonry walls and windows.

A typical Mistrale 75 solution comprises of a 50 or 75mm pitch external weather proof louvre behind which sits an insulated air volume control damper which regulates both the movement and volume of air from the outside to the inside and vice versa. On the internal wall we can then fit numerous types and styles of decorative covering fascia grille. Additional components such as silencers to reduce break through of traffic or other noise into the building and heating/cooling coils can also be included.

Its slimline design and low weight level allow the unit to not only fit on walls but also comfortably bead into a window aperture. This provides for numerous flexible fitting arrangements. The solution comes complete with either a glazing bead to allow fitting into standard window frame or border flanges for convenient wall installation.

Key Performance Features

  • U Value: 0.96 Watts/m2/K
  • Leakage: less than 5m3 per hour per sq/m
  • Weather Rating: Up to Class A
  • Size Range: 350×233 up to 2132×907 as standard (with larger sizes available)
Importantly our insulating damper has high insulation properties providing a U value of just 0.96 watts/m2/K. This is as good as a standard double glazed window and the air leakage rate (when closed) is also low rating at less than 5m3 per hour per square metre. 


Single units can be built into the wall or glazed into the window frame and multiple units to support large screen or continuous run louvres are also available

Mistrale 75 is designed to provide smooth, accurate and stable natural ventilation airflow. The volume control damper is a new and unique design that offers extremely low leakage (when closed) as well as a very low u value. Configured using insulating UPVC extrusions with integral air gaps, cold bridge effects and heat transfer are dramatically reduced creating a unit with an extremely low U value.

The system works automatically with the damper typically actuator driven in accordance with a demand signal from the building controls. Total integration into the building control strategy is also possible either using Gilberts own control system or a full building management suite.

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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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