There is no single price for installing a commercial extractor fan, because a "commercial extract" job might be a single duct fan above a washroom or a plant-room centrifugal serving a whole restaurant kitchen. What you can do is break the cost into four parts that every job shares, get a realistic range for each, and add them up for your own project. This guide does exactly that, with worked examples by project type, so you can budget before you get a contractor in.
Quick answer: For a straightforward light-commercial extract fan (office, washroom, small retail) budget roughly £450 to £1,200 installed, of which the fan is often the smaller part. A centrifugal or plate-axial system with longer ductwork, controls and commissioning runs £1,500 to £6,000+. Commercial kitchen extract is a job of its own. Browse fans in commercial extractor fans, or see which fan suits your job in our best commercial extractor fans guide.
In this guide
The four parts of an install cost
Whatever the project, a commercial extract installation is the sum of the same four line items. Getting each one roughly right is far more useful than chasing a single headline figure, because the split shifts with the job. On a simple washroom fan the labour and electrics dominate; on a plant-room system the fan and ductwork do.
| Part | Typical share of a light-commercial job | What drives it up |
|---|---|---|
| Fan | 25 to 45% | Air volume, pressure, EC motor, low noise |
| Ducting and terminals | 15 to 30% | Run length, bends, rigid vs flexible, roof or wall termination |
| Labour | 25 to 40% | Access, working at height, ceiling or roof penetration |
| Controls and electrics | 10 to 25% | Speed controller, isolator, new circuit, commissioning |
1. The fan itself
Commercial extract fans span a wide price range because they do very different jobs. A light-duty inline duct fan for a washroom or small office is the cheapest option; a low-noise EC box fan or a high-pressure centrifugal for a long duct run costs more but earns it in performance and running cost. Below are current guide prices from our range to anchor your budget.
| Fan type | Best for | Guide price (fan only) |
|---|---|---|
| Inline mixed-flow (silent duct fan) | Quiet office and washroom duct extract | £90 to £250 |
| Inline centrifugal duct fan | Longer runs, higher resistance | £250 to £500 |
| EC-motor centrifugal box fan | Continuous-duty, low running cost | £600 to £1,200 |
| Plate (cased) axial fan | Through-wall workshop and warehouse extract | £300 to £900 |
An EC (electronically commutated) motor costs more up front but uses markedly less electricity and gives you infinitely variable speed control. On a fan running most of the day, the running-cost saving usually pays back the difference within a couple of years. See the trade-off in our buyer's guide.
2. Ducting and terminals
Ductwork is the part most people underestimate. The fan is one box, but the ducting is every metre between the fan and the outside, plus the grille or louvre at each end. Rigid galvanised or plastic duct is dearer to buy and fit than flexible, but it holds its shape, keeps the pressure loss down and lasts. Flexible ducting is cheaper and quicker but adds resistance, so it can force you into a bigger fan.
As a planning figure, budget £15 to £40 per metre for supplied-and-fitted rigid duct on a light-commercial job, more where it runs through a roof or across a plant room. Add the terminals: an external weather louvre or roof cowl to stop rain and birds, and an internal grille or valve. Every extra bend costs both money and static pressure, which is why a short, straight route is worth designing in from the start.
3. Labour
Labour is where quotes vary most, because it depends almost entirely on access. A fan swapped into an existing duct with a working platform below is a couple of hours; the same fan behind a fixed ceiling, up a roof, or in a live commercial space out of hours is a very different bill. As a rough UK guide, a competent ventilation or electrical contractor charges £250 to £500 a day, and most light-commercial single-fan installs take between half a day and two days.
Watch the access cost. Working at height, roof penetrations, scaffold or a cherry picker, and out-of-hours working in an occupied building can each add more to the bill than the fan itself. Get these confirmed in the quote, not discovered on site.
4. Controls, electrics and commissioning
A commercial fan rarely just plugs in. Budget for a local isolator, often a speed controller to set the fan to the design airflow, and sometimes a new dedicated circuit from the board. Where the fan is part of a system that has to meet a ventilation rate, commissioning (measuring and adjusting the airflow to the design figure) is a real line item and, on regulated jobs, a required one. Allow £150 to £600 across controls, electrical connection and basic commissioning on a typical light-commercial install, more for multi-fan or BMS-linked systems.
Worked examples by project type
Putting the four parts together, here is how three common commercial jobs tend to add up. Treat these as planning ranges, not quotes.
| Project | Fan + ducting + terminals | Labour + electrics + commissioning | Typical total installed |
|---|---|---|---|
| Single washroom / small office extract | £200 to £500 | £250 to £700 | £450 to £1,200 |
| Retail unit or gym, longer duct run + controls | £600 to £1,600 | £600 to £1,800 | £1,200 to £3,400 |
| Plant-room centrifugal or workshop plate axial | £1,200 to £3,500 | £1,000 to £3,000+ | £2,500 to £6,500+ |
Commercial kitchen extract is a specialist job with a canopy, grease filters, fire-rated ducting and often a make-up air supply, so it sits well above these figures. We cover it separately in our kitchen extractor fan installation cost guide.
Where the money is really spent (and saved)
The single biggest lever on the total is the ductwork route. A fan sized for a short, straight, rigid run can be smaller, quieter and cheaper to run than the same job forced through long flexible duct and multiple bends. Time spent on the route at design stage saves fan cost, labour cost and running cost for the life of the system. The second lever is buying the fan on trade terms rather than through the installer's markup: sourcing the fan and terminals directly and having your contractor fit them is a common way commercial buyers take 20 to 40% out of the equipment line.
Undersizing to save money almost always backfires. A fan that cannot shift its rated air once the real ductwork is connected leaves you with poor extract, a noisy fan running flat out, and a second visit to put it right. Get the air volume and static pressure right first, then look at price.
Related guides
To choose the right fan before you cost the install, see our best commercial extractor fans guide and browse the full commercial extractor fans range. For the specialist kitchen case, read the kitchen extractor fan installation cost guide. Not sure what you are looking at on an existing site? Our Fan Finder identifies a fan from a photo.
FAQs
How much does it cost to install a commercial extractor fan in the UK?
For a straightforward light-commercial extract fan in an office, washroom or small retail unit, budget roughly £450 to £1,200 installed. Larger centrifugal or plate-axial systems with longer ductwork, controls and commissioning run from about £1,500 to £6,000 or more. The fan itself is often the smaller part of the total; ducting, labour and access drive most of the variation.
Why is the fan cheaper than the installation?
Because the fan is one component and the installation is everything around it: metres of ductwork, an external terminal, an internal grille, an isolator and speed controller, the electrical connection, and the labour to fit all of it, often at height or behind a ceiling. On a simple job the labour and materials around the fan commonly cost more than the fan.
Can I supply my own fan and have a contractor fit it?
Yes, and commercial buyers frequently do to avoid an installer's equipment markup. Buying the fan and terminals on trade terms and having a competent ventilation or electrical contractor install them typically takes 20 to 40% off the equipment line. Make sure the fan you buy is correctly sized for the airflow and static pressure of the job before you order.
Does a commercial extractor fan installation need to be commissioned?
Where the fan forms part of a system that has to meet a specified ventilation rate, yes: commissioning means measuring the actual airflow and adjusting the fan to the design figure, and on regulated projects it is required and should be recorded. A single replacement fan on an existing duct may not need formal commissioning, but setting it to the right speed with a controller is always worth doing.
What adds the most to a commercial fan installation cost?
Access and ductwork. Working at height, roof penetrations, scaffold or access equipment, and out-of-hours working in an occupied building can each add more than the fan costs. Long duct runs with multiple bends increase both material and labour, and can force a larger, dearer fan. A short, straight, rigid duct route is the cheapest system to buy, fit and run.