EnviroVent vs Greenwood Airvac: Which Humidity Fan for a Rental Property?
These are the two fans we fit most. Both are British manufacturers, both make genuinely good continuous-running humidity fans, and neither is a bad choice. But they are not interchangeable, and after fitting a lot of both across Greater Manchester rental stock we have clear views on where each one belongs.
Quick answer: EnviroVent's filterless fans are the stronger choice for tenanted property where nobody will ever service the unit — there is no filter to clog, so performance does not quietly decline over three years. Greenwood Airvac's continuous-running humidity fans are excellent, well-stocked and better value per unit, which makes them the sensible specification for planned replacement across a portfolio of sound properties. Both run continuously and boost on humidity, which is the thing that actually matters. Supplied and fitted, Greenwood is £330 + VAT and EnviroVent £430 + VAT — both including drilling through the external wall, ducting and certification. Call 0161 706 1360 for a survey.
The Two Manufacturers
EnviroVent are a Harrogate-based manufacturer whose business has been built largely around solving condensation and mould in housing, including a great deal of social housing work. Their filterless extract fan designs are the product we reach for most in tenanted property, because they remove the maintenance dependency that kills fans in rentals.
Greenwood Airvac are one of the longest-established names in UK domestic ventilation, with a broad range of wet-room extract fans and continuous-running unitary fans with humidity sensing. Solid, conventional, widely stocked and well understood by the trade.
The difference is not build quality. It is that EnviroVent's filterless range is engineered around a specific failure mode — the unserviced fan — and Greenwood's range is engineered around supplying good, cost-effective ventilation equipment.
Comparison at a Glance
| | EnviroVent filterless | Greenwood Airvac | |---|---|---| | Continuous running | Yes | Yes, on continuous unitary models | | Humidity tracking and boost | Yes | Yes | | Filter to maintain | None | Conventional servicing on some models | | Performance over time | Holds up without intervention | Depends on servicing where fitted | | Typical unit cost | Higher | Lower to mid | | Trade availability | Specialist channels | Widely stocked, usually next day | | Best fit | Tenanted property, active damp complaint | Planned portfolio replacement, sound stock |
Where We Specify EnviroVent Filterless
When nobody will ever service the fan. This is the whole argument, and it is a strong one. A filter in a bathroom fan collects dust, lint and moisture until it is effectively solid. In a tenanted property, nobody is going to take the cover off and deal with it — not the tenant, who does not know it is there, and not the landlord, who is not in the building. Airflow declines gradually and invisibly until a mould complaint arrives two years later. A fan with no filter cannot fail that way.
When there is an active damp and mould complaint. Where a landlord is responding to a formal complaint or a council notice, we specify the most robust option available and document it. With the Renters' Rights Act now in force and Awaab's Law duties expected to reach the private rented sector from 2027, being able to evidence a durable ventilation solution matters — see our guide to damp, mould and the Renters' Rights Act.
Properties with a history of repeat problems. If mould has come back twice in the same property, whatever is fitted is not working and the fix needs to be one that stays working without anyone attending.
HMOs and high-occupancy property. More people, more showers, more moisture, and less chance of anyone taking responsibility for maintenance. See electrical safety standards in HMOs.
Where We Specify Greenwood Airvac
Planned replacement across a portfolio. If an agent has forty properties with tired light-switch timer fans and no acute damp problem, the objective is a compliant, continuous-running humidity fan in every bathroom and kitchen at a sensible cost per unit. Greenwood does that job properly, and across forty properties the unit cost difference is real money.
Sound, well-maintained property. A reasonably insulated property with a bathroom that simply needs proper extraction does not need the premium answer. It needs a good fan, correctly sized, correctly ducted and running continuously with humidity boost.
Where availability drives the programme. Greenwood being widely stocked means we can usually get units next day. On a void property where the re-let date is the constraint, that matters — see void period compliance.
Where the landlord does service their stock. Some of our block management and housing association clients have genuine planned maintenance regimes. If filters will actually be changed, the filterless premium is harder to justify.
The Comparison That Actually Matters
This is the uncomfortable part of the article, from an installer who fits both: which brand goes on the wall is a second-order decision. In rough order of what actually determines whether ventilation works:
1. Does it run continuously? Anything that only runs with the light switch is compromised in rental property. Summer showers with the light off produce moisture and no extraction. 2. Is the ducting right? Short, straight, correct diameter, falling to the outside, insulated through any cold void, terminating outside the building. Every bend and every crushed metre costs airflow. 3. Is the external terminal any good? A cheap grille with tight fly mesh and stiff flaps can halve the delivered rate of an excellent fan. 4. Was it commissioned? Rate measured with an anemometer, not assumed from the box. 5. Whose badge is on the front.
We have replaced premium fans that were doing nothing because they discharged into a soffit void, and we have found budget fans working perfectly after a decade because someone ran a short straight duct through the wall to a decent cowl.
If someone quotes you a premium brand and a cheap installation, you are buying the wrong half of the job.
Typical Costs
| Specification | Supplied and fitted | |---|---| | Greenwood Airvac humidity fan | £330 + VAT | | EnviroVent filterless fan | £430 + VAT |
So the decision costs you £100 + VAT per fan. That is the whole commercial question, and it is worth framing plainly: across a single problem property the difference is trivial next to one mould complaint, and across forty routine replacements it is £4,000.
Both prices include the fan, core drilling through the external wall, the wall liner and ducting, the external terminal, the electrical connection, making good, commissioning and certification. Neither is a supply-only price with extras added later.
Unusual wall construction, difficult access or a property needing new circuit work can move the price, and we confirm on survey before booking. Portfolio work is priced on an agreed schedule of rates.
How We Decide, On Site
The survey is short and it is the same every time:
Where is the mould? Bathroom and kitchen points to extraction at source. Bedrooms and external corners as well means the moisture is spreading through the property before it can be extracted, and both wet rooms need dealing with properly.
What is fitted now, and does it move any air? We measure the existing rate. A surprising number of fans read close to zero.
Where does the existing duct actually go? In older Manchester conversions, more often than we would like, into a loft or a soffit void.
What is the wall? Nine-inch solid brick, cavity, or stone changes the through-wall install and the price.
Who lives there and what is the risk? A vulnerable occupant, an HMO, or an existing complaint gets the robust specification, not the cheapest one.
Then we specify. Sometimes that is EnviroVent, sometimes Greenwood, and often a mix within the same portfolio — filterless units in the problem properties, Greenwood across the routine replacements. There is no reason to standardise on one badge when the buildings are not standard.
Frequently Asked Questions
Is the EnviroVent premium worth paying?
The premium is £100 + VAT per fan. In tenanted property where no one will service the fan, generally yes — you are buying performance that does not decay, and £100 is less than a single call-out to look at why the fan is not working. On sound stock with a real planned maintenance regime, Greenwood at £330 + VAT is very good value and we fit plenty.
Can I mix brands across a portfolio?
Yes, and we recommend it. Match the specification to the property rather than to a purchase order. There is no technical or warranty reason they cannot sit side by side across a portfolio.
Which one lasts longer?
Both manufacturers produce units with a realistic service life well into a decade in domestic use. In our experience, failures are far more often installation-related — condensation running back down a duct into the fan, or a unit fighting a strangled run — than manufacturing defects.
Do they come with a guarantee?
Both provide guarantees, with terms that vary by product line and change over time, so we confirm the current position at quotation rather than stating it here. Our installation workmanship is covered separately.
What about cheap online or supermarket fans?
The unit may be adequate for a homeowner. For rental property we do not recommend them, because they are typically light-switch-linked intermittent fans with a short overrun — the control strategy that fails in tenanted property, for the reasons set out in our humidity-tracking fans guide. The problem is not the price, it is the design.
Can you supply and fit across a whole portfolio?
Yes. We run ventilation upgrade programmes for landlords, letting agents and block managers across Greater Manchester, priced on a schedule of rates and programmed alongside EICR and remedial visits so each property is attended once.
Get a Specification, Not a Sales Pitch
Manchester Compliance installs both EnviroVent filterless fans and Greenwood Airvac humidity fans. We are not tied to either, which means the specification you get is the one that suits the building. We survey, measure what is actually there, tell you what the problem is, and quote for the fix.
Call 0161 706 1360 Email: hello@manchestercompliance.co.uk
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