Industrial roof ventilators for passive ventilation come in many different shapes and sizes and are suitable for most factory, warehouse and maintenance facilities to name a few.

A traditional passive roof ventilator sits on the ridge of a roof as this is the highest point of the roof and the optimal position to exhaust the warm buoyant internal air. The following image shows the basics of passive ventilation airflow:

SL600 Front installaed

Inlet air also know as make up air must be allowed to flow into the building, ideally at low level to replace the warm buoyant air that is expelled through the roof vent, thus creating airflow.

New buildings can be designed to accommodate ridge mounted ventilators quite easily. This is not quite as easy on retro fit schemes as the ridge purlins are generally too close together to make a ridge vent viable. The solution in these cases is to use a slope or pitch mounted ventilator, basically a ridge ventilator with slightly different flashing that allow them to be mounted down the slope. The optimal position for a slope mounted ventilator is as close to the ridge or highest point of the roof as possible

Roof vents can be manufactured from zincalume, Colorbond, galvanised steel or aluminium and can include automatic dampers to regulate the airflow during cooler months.

The size and quantity of ventilators required depends on many factors:

  • Size of building- Height x Width x Length
  • Heat load within the building – Machinery, personnel, etc.
  • Building fabric- Concrete, steel and is it insulated
  • Required air changes per hour AC/Hr

Passive ventilation can be a cost effect way of ventilating a building providing the system is designed correctly.

For more information and to request a free survey pleas contact us.