Roof centrifugal fans — high static pressure roof extraction with low noise

Centrifugal roof fans combine the benefit of roof mounting with the high static pressure performance of the centrifugal rotor — a decisive advantage over axial roof fans when air must be extracted through a vertical duct network, or when noise is an important constraint. The backward-curved blade centrifugal rotor generates static pressures of 200–800 Pa, sufficient to overcome the resistance of a long vertical duct, filters and ceiling-level extract grilles.

The specific equipment for centralised ventilation of commercial and office buildings where stale air is collected from multiple floors or zones through vertical ducts exiting on the roof, hotels with centralised extraction for bathrooms and corridors, hospitals and clinics where vertical ventilation ducts collect air from multiple areas, shopping centres with centralised toilet extract, and restaurants with centralised extraction. Significantly lower noise levels than axial roof fans — due to the nature of the centrifugal rotor — make them preferred in buildings with acoustic comfort requirements.

How to choose: determine the required static pressure along the complete circuit — from the extract point in the space, through the vertical ducts, to the roof unit. If it exceeds 150–200 Pa, centrifugal roof fans are the only viable option in this category. Verify that the roof unit connection dimensions are compatible with the existing or planned vertical duct diameter.

👉 Axial roof fans — for high airflow without internal ductwork 👉 EC motor roof fans — the energy-efficient variant