Destratification Fans

Destratification fans — also called anti-stratification fans, destrat fans, sweep ceiling fans or ceiling sweep fans — solve the single biggest energy waste in any tall heated building: warm air rising and sitting uselessly against the roof while the occupied zone stays cold. eFans is a UK Hydor stockist and supplies the full Hydor HCF destratification range: HCF900 (36"), HCF1200 (48") and HCF1400 (56").

All three are 1-phase, single-speed AC motors, speed-controllable via a standard fan speed controller, and designed for permanent ceiling mounting in warehouses, factories, distribution centres, workshops, gymnasiums, sports halls, churches, village halls, agricultural buildings and any space with high ceilings and gas, oil or electric heating. Running a correctly sized destratification fan typically pays back the purchase price within one heating season on reduced gas or electricity bills. In UK stock with next-day delivery and trade pricing on multiple-unit installs. 

Commercial Ceiling Fans / HVLS Fans / Warehouse Heaters / Speed Controllers

What are destratification fans?

Destratification fans are ceiling-mounted sweep fans that mix the warm air trapped near the roof of a tall heated building back down into the occupied zone. In any heated space, warm air is less dense than cold air and rises — in a typical 6–10m warehouse or church, the temperature at the apex can easily be 8–15°C warmer than at floor level. That stratified warm air does nothing useful; the heating system is forced to run harder and longer to keep the occupied zone comfortable. A destratification fan pushes that warm air back down, evens out the temperature profile top-to-bottom, and cuts heating demand typically by 20–30%.

How do destratification fans work?

Unlike HVLS fans, which move huge volumes of air for occupant cooling at low speed, destratification fans are smaller, faster and purpose-designed to recirculate warm ceiling air. The Hydor HCF range uses a traditional-style sweep ceiling fan blade running at moderate speed, directed downward, to pull the hottest air down from the apex and mix it back through the occupied zone. Fans can usually run continuously through the heating season on a low speed setting, or be wired through a thermostat or controller that triggers them when roof-level temperature exceeds a setpoint. Noise levels are low enough for occupied office, retail and place-of-worship applications.

How to choose the right destratification fan

Selecting the right destratification fan depends on the size, height, and use of your commercial or industrial space. Consider ceiling height, as higher ceilings require more powerful fans to effectively circulate warm air. 

Airflow rate (measured in m³/h) is key to ensure the warm air is redistributed efficiently without creating drafts. Fan type, energy efficiency, and noise levels should also be evaluated to suit the environment.

Which Hydor HCF size do I need?

Hydor HCF900 (36"/900mm) suits smaller workshops, offices, classrooms and spaces up to roughly 4–5m ceiling height. HCF1200 (48"/1200mm) is the most common choice — warehouses, factory units, gyms, village halls and churches with 5–8m ceilings. HCF1400 (56"/1400mm) is specified for large industrial units, distribution centres, sports halls and high-ceilinged churches with 7–10m+ apex. As a rule of thumb, one HCF1200 covers roughly 100–150m² of floor at typical warehouse ceiling heights; space fans on a grid rather than clustering them. For ceilings over 10m or buildings with radiant tube or warm-air heaters aimed high, consider HVLS fans instead or in combination.

What buildings use destratification fans?

Warehouses, distribution centres, light industrial units, engineering workshops, MOT bays, vehicle showrooms, agricultural buildings and barns, gymnasiums and sports halls, swimming pool halls, churches and places of worship, village halls and community centres, school halls, large retail units, garden centres, and any commercial or industrial space with a heated apex above 5m. The payback is strongest in buildings heated by gas warm-air heaters, radiant tubes, oil-fired unit heaters or electric overhead heaters — all of which tend to deposit heat upward and suffer badly from stratification.

How much energy do destratification fans save?

Typical savings are 20–30% of heating fuel cost in a stratified building, though some installs report higher. The saving depends on ceiling height (taller = bigger gradient = bigger saving), heating system type (warm-air and radiant benefit most), insulation quality, and how long the heating runs. Payback on a Hydor HCF1200 installed in a typical UK warehouse is usually under one heating season on reduced gas bills alone. Fans themselves consume very little electricity — typically 60–120W each depending on size and speed — so the net saving is almost entirely captured.

Are Hydor HCF fans speed controllable?

Yes. All three Hydor HCF fans — HCF900, HCF1200 and HCF1400 — are single-phase AC motors that work with standard fan speed controllers. For most destratification applications the fan runs continuously at a low speed through the heating season, so a simple 5-step controller or electronic speed controller is specified alongside. For multi-fan installs we recommend one controller per zone or per three-to-five fans rather than trying to drive an entire warehouse off a single small controller. Wire through a thermostat or timer if you want the fans to switch off in summer or outside working hours.

Destratification fans or HVLS fans — which is right?

Destratification fans (Hydor HCF) are the right choice for most UK warehouses, factories, churches and sports halls with ceilings between 5m and 10m. They are smaller, much cheaper, quick to install, and purpose-designed to mix warm ceiling air downward. HVLS (high-volume low-speed) fans are 7–24ft sweep fans designed primarily for summer cooling in large open spaces, and for destratification in very tall or very large buildings (10m+ ceilings, 2000m²+ floor plates). For most SME commercial and industrial buildings, a set of HCF1200s on a grid is the cost-effective answer. HVLS pays off where the floor area or ceiling height makes multiple smaller fans impractical.

At what height should destratification fans be mounted?

Mount as high as practical — as close to the roof apex as the structure allows — so the fan draws from the hottest layer. A typical install uses a downrod or drop-rod to position the fan blades 500–1000mm below the apex, clear of any roof trusses or services. Minimum clearance from floor to blade tip should be 2.7m for occupant safety. In pitched-roof buildings, fans are usually sited under the ridge line and spaced down the length of the building. Ensure fixings are made into structural steelwork or a suitable timber purlin — never into plasterboard or a suspended ceiling alone.

Can destratification fans be used in cold or unheated buildings?

Only if there's a meaningful temperature gradient to destratify. In an unheated barn or warehouse with no heating source, there's no stratified warm layer to recirculate, so a destratification fan adds nothing. The same fan can however be run in summer on a higher speed for occupant cooling — functionally the same as a traditional ceiling fan — so the purchase isn't wasted if the building is used year-round. For buildings that are only occasionally heated (churches, village halls, weekend-use units), fans can be wired on the same circuit as the heating so they come on together.

How many destratification fans do I need for a warehouse?

The number depends on ceiling height, floor area, heat source layout, and zoning. Large warehouses usually need several evenly spaced units to ensure balanced airflow and full coverage. A proper airflow assessment avoids dead spots and optimises performance.

Are destratification fans suitable for sports halls and leisure centres?

Yes. They work well in sports halls, gyms, and leisure centres with high ceilings, where warm air gathers above the occupied zone. Destratification fans reduce temperature differences, improve comfort, and help lower heating costs by smoothing HVAC loads.