HVLS Industrial Fan Sizing Calculator
Estimate the blade diameter and number of HVLS (High-Volume, Low-Speed) fans a factory, warehouse or workshop needs. Enter your floor dimensions and ceiling height to get a transparent, rule-of-thumb starting point for air-circulation planning across Thailand and ASEAN.
How to use it
Enter the length, width and ceiling height of the space in metres, then pick the closest application type. The calculator suggests a standard blade diameter for your ceiling height and estimates how many fans are needed to circulate air across the whole floor.
You can override the suggested diameter with any standard catalogue size to compare layouts — a larger fan covers more area, so fewer units are usually required.
How the estimate is calculated
Coverage is based on a commonly-cited reference figure: a 7.3 m (24 ft) HVLS fan circulates air over roughly 1,860 m² (about 20,000 sq ft) in an open warehouse. Coverage scales with the square of the blade diameter, so smaller fans cover proportionally less area.
Comfort and people-cooling applications need a higher perceived air speed, so effective coverage per fan is reduced and more fans are recommended; open warehouse circulation needs the least. A minimum blade-to-floor clearance of 3 m (about 10 ft) is applied as standard safety guidance.
These are planning estimates only. Confirm the final selection against the specific fan model’s datasheet and, for critical installations, a qualified ventilation engineer.
Frequently asked questions
What is an HVLS fan?
HVLS stands for High-Volume, Low-Speed. These are large-diameter ceiling fans (typically 4–7 m) that move a large volume of air slowly, creating a gentle, wide breeze that is energy-efficient for cooling and destratifying large industrial spaces.
How many HVLS fans do I need?
It depends on the floor area, ceiling height and application. As a rule of thumb, a single 7.3 m fan circulates air over roughly 1,860 m² in an open warehouse; comfort cooling for people needs denser coverage. Use the calculator above for a space-specific estimate.
What size HVLS fan suits my ceiling height?
Higher ceilings suit larger blade diameters. As a guide: under 4 m → about 4.3 m fan; 4–6 m → about 5.5 m; 6–9 m → about 6.1 m; above 9 m → about 7.3 m. Always keep at least 3 m of clearance between the blades and the floor.
Need the actual fans?
ASEAN Machine sources large industrial HVLS fans and other air-movement equipment from vetted China manufacturers, with delivery and support across Thailand and ASEAN. Send your dimensions and we will help confirm the right model.