Ventilation Systems

Bormioli Luigi S.p.A. – Natural ventilation

Client: Bormioli Luigi S.p.A.
Location: Facility in Abbiategrasso, Italy
Kind of project: Design and installation of a natural ventilation system in the compressor room of the Bormioli factory (where glass products are produced).
Description: The aim of the project was to supply the compressor room with an air recirculation system, evacuating heat produced by the compressors and other machines inside the space.

Design of the natural ventilation system was conducted bearing in mind the following variables:

    • The kind of structure involved
    • Configuration and eventual use of the building
    • Layout of machinery
    • External environmental conditions: sunny days, summer season, average temperature 25° Celsius.

On paper, the building had a total surface area of roughly 522 sqm. Inside there were two closed spaces set up for other uses (a generator group; a transformer room) and covering 167 sqm. The average surface area of the main space was approximately 355 sqm. The building includes a compressor room. The machinery present inside the room generate heat.
The thermal gradient in relation to the height of the building is 1°C/m.

Calculations for the ventilation were made bearing in mind conditions during a sunny day, during the summer season with an average temperature of 27° Celsius.


Fresh air enters from below through grilles that are always open. The airflow passing through the intake grilles was analyzed in a wind tunnel. Four MLS-1 air intake grilles were installed, positioned on sandwich panels located on the walls adjacent to the transformer space, for a total of 12 sqm.

The natural ventilation system for the compressor room was created with a labyrinth structure built of marine aluminum, positioned near the roof’s apex.
The UNILAB labyrinth natural ventilators were designed to extract large volumes of hot air under all weather conditions. A system of staggered marine aluminum plates gathers all the water that penetrates the main body of the building, discharging it externally to the side.
A 20.00-meter long and 1-meter wide opening was created in the roof. The UNILAB has a closure slit activated by a pneumatic cylinder. A control station positioned at the bottom opens and closes the natural extractor.



This natural ventilation system configuration will make it possible to obtain considerable performance levels:

  • Airspeed of exiting air: 1.94 m/s
  • Air exchange volume: 33,189 mc/h
  • Air exchange: 6.22