Roof Fans

63 products

Roof fans mount on a kerb or upstand and discharge straight to atmosphere at roof level, with no ductwork on the discharge side, which keeps installation cost and system resistance down. They are the standard answer on warehouses, factories, retail units and commercial kitchens, and anywhere there is no suitable external wall to extract through. We stock roof fans from Systemair, S&P, Elta and Vent-Axia from 150mm to 710mm, in single and three phase, on UK stock with next-day delivery. Use the buttons below to filter by supply, or for quotes and sizing help, email hello@efans.co.uk or call 0161 399 3825.

Frequently asked questions

Vertical or horizontal discharge roof fan?

Vertical discharge fans exhaust air straight up. They are the most common type and work well in most applications, but near air intakes on taller neighbouring buildings the exhaust plume can rise and be drawn back in. Horizontal discharge fans, sometimes called mushroom fans, throw the air outwards and downwards so it disperses more quickly. They are the better choice near building boundaries, where vertical discharge could be re-entrained, or where planning limits visible roof equipment.

What should I check before ordering a roof fan?

A roof fan has to match its roof kerb, the base that sits on the roof and keeps the opening weatherproof, so check the kerb dimensions against your existing or planned opening. Check the supply at roof level too: single phase suits the smaller sizes, and most larger units are three phase. For kitchen extract, the fan must be rated for grease-laden air and elevated temperatures. A standard roof fan on a kitchen extract is a fire risk, so see our commercial kitchen extractor fans instead.

How do I size a roof fan?

Size from the airflow the space needs and the resistance on the inlet side: any ductwork, grilles or filters feeding the fan. For large buildings, several smaller roof fans spread across the roof often give more even extract than one large unit, and keep some ventilation running if one unit is out of service. Send us the building dimensions and the duty and we will size it.

Single phase or three phase?

Smaller roof fans are usually single phase and run from a standard 230V supply. Larger units are mostly three phase. Use the buttons below to filter the range by supply, and check what is available at roof level before choosing, because running a new three phase supply to the roof adds cost.

Can a roof fan be speed controlled?

Most can, with a controller matched to the fan motor and its full load current. Each product page lists the motor type and current. Tell us the fan and we will match a controller from our speed controllers.

Single Phase Three Phase