destratification fans; destrat fans; destratification fan; destratification fans UKFlexiheat UK

Destratification Fans / Industrial Ceiling Fans

destratification fans; destrat fans; destratification fan; destratification fans UK

Destratification Fans or Destrat Fans from Flexiheat UK


Destrat Fans – You cannot beat the laws of physics that warm air rises and this process causes thermal stratification, a natural process which causes warm air to rise to the ceiling or roof space and displaces the cooler air, pushing it downwards into the occupied area. With conventional air heating systems, heated air will rise to the roof level by natural convection in high building such as factories, warehouses and sports centres with the cold air falling. This can result in high temperature gradients and consequently increased energy usage. The Carbon Trust estimates that the use of destratification fans in industrial buildings with high ceilings can reduce the consumption by up to 20%, although some other studies show that this may figure may be up to 32%. These Destratification Fans are basically a heat recovery unit or system which save money and benefit from low running costs, even temperature distribution and little to no maintenance requirement.

Warm heated air rises to the roof level by the natural phenomenon of convection in any conventional air heating system. This can lead to significant temperature gradients as the cool air sinks, and as a result, greater energy consumption in elevated buildings such as warehouses, factories, sports centres etc. Fabric heat losses and air penetration are especially problematic in older buildings with insufficient thermal insulation and numerous leakage spots. The benefits of destratification or a destratification system are numerous, but energy savings are the foremost.

Destratification fans are a highly efficient, cost effective, and eco friendly solution to prevent wasted heat as warm air rises by natural convection by recirculating warm air back to the occupied space.

The natural convection process of warm air rising is reversed by the destratification fan, as the hot air flow is directed by the fan blades, recirculating warm air, and eliminating the temperature difference in the occupied space (i.e., high temperature gradients) which reduces energy consumption with uniform temperature distribution within commercial or industrial buildings with a HVAC system.

Flexiheat UK’s range of destratification fans reverse the natural convection process, re-circulating the warm air back to working levels and provide a permanent reduction in roof space temperature and uniform temperature distribution within the building , via thermal destratification

The Benefits Of Destratification Fans / Industrial Ceiling Fans

  • Increased energy efficiency means lower heating costs.
  • Lower energy costs / reduce energy consumption.
  • Reduced roof space temperature
  • Optimum air distribution to prevent hot and cold spots in industrial buildings and provide a comfortable environment
  • Hot and cold spots are eliminated or reduced dramatically, with even temperature distribution.
  • Improved comfort for the workforce or your customers: good temperature distribution
  • Potentially fewer heaters are required for your warm air heating system so you can reduce your energy consumption.
  • Can be used for a “cooling effect” in the summer for improved comfort levels.

                 Before                                                                        After

destratification fans,destratification fans in churches,destrat fans                         destrat fans, destratification fans,industrial ceiling fans,destratification fans uk

Without  destratification / Destrat fans installed

As you can see in the above before picture,  the ceiling is hot and the floor area is cold due to the warm air rising. To get the required temperature at floor level you have to heat up repeatedly, even though the ceiling area is already 26°C.  The high temperature of the ceiling causes a corresponding high energy loss at the ceiling.  Often some areas of the room stay cold after prolonged heating by a warm air heating system.

With destratification / Destrat fans installed

Our industrial ceiling fans equalise the room temperature by pushing down and mixing the warm air. As you can see in the above after picture, this results in a  5°C higher temperature at the floor without any additional heating, meaning 30% fuel savings. If we have an outside temperature of 0°C and you can  reduce the temperature from 31°C to 21°C at the ceiling, the energy usage is reduced by 32%. This results in much more even temperature gradients throughout the building, with no cold spots, and makes the most of your warm air heating system.

The Carbon Trust rates destratification fans as one of the best carbon-reducing initiatives for any type of building and as one of the easiest energy-reduction technology that can be installed in existing as well as new buildings.

The most commonly used de-stratification fans are;-

Higher velocity fully encased destratification fans – These are the most popular thermal destratification fans that we sell. They are suitable for mounting from 6 metres all the way up to the 15 metres in height, and are ideally suited to commercial and industrial premises, such as warehouses, exhibition halls and supermarkets etc to ensure even temperature distribution within the building and reduce wasted heat.

Leo D destratification Fans; destratify fans; destrat fans;

” LEO D ” Destrat Fan range for sale from Flexiheat UK

This range of thermal destratification fans are the LEO range , and can come in 3 versions – from a simple on / off manually controlled unit , a unit with an integral thermostat that will thermostatically control units based on the air temperature and lastly a fully automatic unit, that can be used with a BMS ( building management system ) or its own fully automatic intelligent controller – which has many control functions, such as fan speed, temperature control etc.

Low velocity – blade or propeller fan (also known as Punkah fans or sweep fans) – These work by churning the air as they rotate anti clockwise, and force the warm air at the ceiling or roof level downwards back to the ground level, where its required. This de stratifying effect on the air results in an improved climate, and improves the energy efficiency of the warm air heating system and are most appropriate for ceiling heights between 3 metres  and 10 metres (pictured below )

destratification fans,destrat fans,industrial destratification fans,industrial ceiling fans.destratification fans uk

High velocity axial fan models with air diffuser fitted – Suitable for buildings with very high ceiling heights of up to 30 metres – These send a significant amount of air at high speed towards the floor and are best for mounting heights of up to 30 metres (pictured below)


destratification fans,destrat fans,destratification fan; destratification fans uk;

Destratification fans or destrat fans from Flexiheat UK – Turbo confuser attachment

We do all three versions of these destratification fans at Flexiheat UK

Commercial destratification fans – Leo Range 

 The primary function of these commercial destratification fans or under-ceiling air mixers is counteracting the accumulation of warm air in the roof space of the building. An axial fan draws warm air in and forces its flow downwards, i.e. towards the zone occupied by people (the thermal comfort zone).  This results in a reduction of heat losses through the ceiling and causes faster heating of the building and lowers the fuel consumption of space heating system by eliminating the thermal stratification of the warm air.

All of these commercial and industrial destratification ceiling fans are manufactured with an EPP casing (expanded polypropylene), which is a remarkable plastic which provides a unique range of properties, which include an exceptionally high strength to weight ratio, high impact resistance, high water and chemical resistance and is also 100% recyclable. These benefits make our units not durable, but also light in weight – an example of this –

A Powrmatic CECx4500 de-stratification fan weighs 29kg’s whilst our equivalent model the Leo D XL weighs in at only 19.5 Kg’s ,which is a weight saving of 32.7% that is not insignificant , and needs to be considered with regards to the weight loading of the roof of the building and also how much easier these units are to install.

All of these de-stratification fans are manufactured in an aesthetically pleasing and neutral colour of grey which is very close to RAL 9007, and have 3-speed, energy saving ErP compliant fans fitted as standard.

The air outlet of these units is equipped with 4 sections of adjustable air louvres. Each louvre can be easily adjusted manually, discharging the warm air in any direction to suit the site conditions and returning useful heat back into the working zone.

commercial destratification fans; thermal destratification ceiling fans; ceiling destratification fans;

Our Leo range of Destrat Fans – adjustable air outlet grid that is standard on all units

This range of commercial destratification fans are equipped with corner holders / brackets, which make the installation and levelling of the units under the ceiling much easier.

We do three versions of these units –

1.” LEO D” without control systems- these are manually controlled by a basic on/off switch

2.” LEO DT” with built in thermostat which switches on the unit when the temperature rises above the set temperature

3.”LEO BMS” are equipped with energy efficient 3 speed fans controlled by a DRV module.  The DRV module manages the operation of the de-strat fans according to control signals from the T-box controller which is an intelligent control system, with an automatic destratification mode matched to individual’s needs or directly from a BMS (Building Management System)

destratification fans uk; destratification fans energy savings; destratification fans in churches; destratification ceiling fans

The Leo “BMS” units can operate fully automatically with a PT-1000 thermostat set at high level, and the T- Box controller at low level – which is also BMS compatible- A fully adjustable destratification system

Technical data for the LEO D range of commercial destratification fans

The Leo Range of fans have quite large air flows compared to other units that “theoretically” cover the same area. The reason is that this range of destrat fans are designed to destratify stratified air, whilst other less capable units that are on the market are designed to prevent stratification happening, as maintaining the de-stratified air takes a lot less air flow, than rectifying stratified air.

All of the units have a 3-step fan, which varies the airflow through the units, and when linked to our T Box intelligent controller, and with a high-level temperature sensor mounted at ceiling height this fully automatic system, will change the fan speeds dependant on the site conditions.

All of these destratification units are powered by a single phase / 240 Volt supply and are rated to IP54 with an insulation class of “F”.

commercial destratification fans; stratification fans; anti stratification fans; air stratification fans


Download the Flexiheat Leo Destratification Fans Brochure

Download the Flexiheat Manual for LEO D Destratification Fans

Product Information on the High Velocity Destratification Fans / Industrial Ceiling Fans

destratification fans,destrat fans,destratification fan; destratification fans uk;

Destratification fans or destrat fans from Flexiheat UK


The ideal destratification solution for buildings with a maximum ceiling height of 30m.  The fan unit is fully enclosed in a protective casing making it particular suitable in areas such as sports halls, and or high ceiling buildings.

These destrat fan units are  IP54 Splash-water proof  and dust proof protected

These are surprisingly quiet and low energy consumption units

Comes complete with a suspension kit, which you should use drop drops or threaded bar to instal these industrial ceiling fans

When installing on surfaces which transfer or suffer vibrations – it is recommended to use anti-vibration mounts – for the drop rod to attach too.

The Turbo XL  industrial ceiling fans are designed for a maximum ceiling height of 30 metres

See the video below – of these units under testing –

Technical Data for our Industrial Ceiling Fans / Destratification Fans for higher industrial or commercial buildings


ModelTurbo XL Destratification Unit
ColourBlack / Grey
Voltage220-240 Volt, 50 Hz
Max Power Consumption450 Watts
Max Current Consumption2 Amps
Air Volume6,300 m3/h
Performanceup to 30 m
Sound level *67.5 dB(A)
Weight25 KG
IP protectionIP54
Motor insulation classF
Test markCE

*Acoustic pressure level measured in a room of average sound absorption, with a capacity of 1,500m3, and at distance of 5 metres from the unit


Download the Brochure for Industrial Ceiling Fans / Industrial Destratification Fans


Product Information on the Low Velocity Destratification Fans

These low velocity fans are open bladed destratification fans and are not suitable for premises or applications where by items may come into contact with the rotating blades such as sport halls, gymnasiums etc. Although these destratification fans are normally the most cost effective to purchase on face value as opposed to the encased high velocity versions, you often have to install more of these fans as the floor area they cover is a lot smaller. Then the associated fitting cost, wiring costs etc have to be factored in as well. However, if you have a smaller type industrial unit or building, with a relatively small floor area and fairly low ceiling or roof height, then these standard destratification fans can not only work out to be a good solution, but a more cost effective solution as well.

low velocity destratification fans; destrat fans; destratification fan;

Product Features and Benefits  –

  • Easy to install and maintain
  • Long life ball bearings and silent automatic shutters
  • Low noise levels
  • Safety cable included
  • Single phase 220V to 240V 50Hz
  • Ceiling mounted air circulation fan

Destrat Fans / Industrial Ceiling Fans accessories –

FHFC1.7  – Electronic fan speed controllers (up to 5 fans)

FHFC3.0 – Electronic fan speed controllers (up to 9 fans)

FHCFC1.7 – Reversible fan electronic controllers (up to 5 fans)    

These low velocity destratification fans are supplied with 2 down rod lengths- A  400mm down rod fitted giving a 610mm overall drop (from ceiling to base of motor body) and a 150mm down rod (supplied loose) giving a 360mm overall drop  (from ceiling to base of motor body)   ***  we highly recommend using the 400mm down rod.

Destratification Fans from Flexiheat UK; destrat fans; destratification fan; stratification fans;

FHCF1200 Dimensions- 360mm overall drop (minimum) or 610mm overall drop (maximum)

**Ideally the fan  should be mounted above the lighting system and with a clearance of at least 610mm between the blades and the roof



Design considerations for Destratification Fan / Industrial Ceiling Fans systems – 

1. Safety First – Ceiling fans have to placed so that there is a minimum distance of 2.3 metres between the floor and the bottom edge of the fan blades

2. Most suitable type of fan for the application – See above with regards to mounting heights of the different de-stratification fans

3. Positioning of the units for optimum air distribution and de-stratifying effect of the destratification system

4. Noise levels – DBA of the units

5. Number of units required

6. Mounting height of the fans to prevent any draughts

Destratification fans

Control options for destratification or destrat fans

There are various control options available –

1.Fan operation can be speed controlled

2.Fans only come on when the heating system is on

3.Speed control of the fans to prevent draughts

4.Fans are controlled independently of the heating system

5.Summer Function for cooling effect – i.e. Reversible control option

How to Size Destratification Fans / Industrial Ceiling Fans

For the high velocity destratification fans – you size these like this –

Consider the mounting height first as this will dictate which type of destratification fan you require. Then calculate the volume of the building and multiply by two to determine the amount of air that needs to be re-circulated for effective destratification. Divide by the primary air flow of the unit to determine the number of fans required.

Alternatively, just let us know these dimensions and we’ll run you building through our destratification fan sizing tool

For example, here’s a 5 mtr length x 5 mtr wide x 7 mtr average height building. We always allow one metre above the fan mounting height.

information required to size destratification fans Flexiheat UK 2021

Information required to correctly size destratification fans for commercial or industrial application.

For the low velocity destratification fans – you size like this –

Which low velocity destratification fan model do I require and how many do I need ? the destratification ceiling fans selection depends upon the height and area of the building.

Mounting heights –

FHCF900 (900mm diameter fan) units for a maximum of 3m mounting height
FHCF1200 (1,200mm diameter fan) units for a maximum of 6m mounting height
FHCF1400 (1,400mm diameter fan) units for a maximum of 9m mounting height

*Please note the ‘mounting height` refers to the distance between the blades and the floor. There must be a minimum distance of 2.3m between the floor and the lowest point of the fan.

Area covered per destratification fan

FHCF900  -1 per 33m²

FHCF1200 -1 per 90m²

FHCF1400 -1 per 145m²

For this guide we will be calculating in metres

1.Calculate the internal height
2.Calculate the length by the width to get the square meters of the internal space
3.Choose the most suitable fan based on the maximum height it can do
4.Divide the square meters of the internal space by the square meters that the chosen fan model can do. This will then give you the number of fans required. See below example

For an internal area of 20m in length, 20m in width and 4m in height, the calculation would be as follows;

20 x 20 = 400m². The height is 4m so the most suitable fan would be the FHCF1200 as it has a maximum height of 6m. This fan has a coverage of 90m², so the next sum would be 400 ÷ 90 = 4.4
As this resulting figure is over 4, you would require 5 fans for this area.

Destratification Fans –  Destrat Fans – Industrial Ceiling Fans for Sale UK & Ireland  

We have a great range of destrat fans to suit all commercial and industrial destratification needs, all are the best quality , and at the best prices. These destrat fans will automatically recirculate the high level warm or hot air from high level , to ground level, thus reducing stratification and any associated heat losses. This movement of the warm air from the ceiling or roof, down to the floor level, not only converts potentially wasted heat or energy back into useful heat, but can also lead to reduced energy bills, as they can save up to 32% depending on the height of the building, warehouse, factory or church .If you require any further assistance with any of our Destratification FansDestrat FanDe-stratification fansIndustrial Ceiling Fans, please click here to contact us via email or call our customer service team direct on 01202 822221.