Roof axial fans — high-airflow roof extraction for halls and warehouses

Roof axial fans are the highest airflow-to-cost ratio roof extraction equipment in industrial ventilation: the axial rotor integrated in a cylindrical or hexagonal casing with a protective cap evacuates large volumes of hot, moist or stale air directly from the upper stratification layer of the hall, where temperatures are highest and natural ventilation is insufficient or impossible.

Unlike centrifugal roof fans, axial variants generate much higher airflows at the same installed power, but at lower static pressure — making them ideal for direct extraction without internal duct networks. The reference solution for tall industrial halls (metalworking, timber, food industry, logistics), large warehouses with high racking, sports halls and leisure centres and any building where hot air must be rapidly and efficiently exhausted through the roof.

The casing is constructed from galvanised steel or anodised aluminium with a profiled cap providing rain, snow and reverse-wind protection. The ventilation.ro range — Casals and Nicotra Gebhardt — covers diameters from 315 mm to 1,250 mm, airflows from 2,000 m³/h to over 80,000 m³/h, single-phase and three-phase, with speed adjustment and optional overheat protection thermostat.

How to choose: calculate the total required airflow for the hall area, air changes per hour, and distribute it across multiple roof units (4–8 m² of roof area per unit is a practical guide). Verify that available static pressure covers the cap and back-draught shutter resistance. For halls below 5 m height or with point pollution sources, centrifugal roof fans may be more appropriate.

👉 Centrifugal roof fans — for higher static pressure 👉 EC motor roof fans — for maximum energy efficiency