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Kitchen extraction cleaning - quality
You paid for an extraction clean - but was the whole system actually cleaned, or just the visible parts? A bad clean leaves tell-tale signs: grease still in the ductwork, the fan skipped, no proper report or photographs to prove the work. Here is how to spot an extraction clean that was done badly, so you know whether you got what you paid for. This is general commentary on cleaning quality.
The short answer
Because much of the extraction is hidden, a badly-done clean can pass at a glance - the visible canopy looks clean - while the hidden ductwork and fan were skimped or skipped. Knowing the tell-tale signs lets you judge whether you got a proper whole-system clean. This is general commentary. What a bad clean looks like. The classic bad extraction clean does the easy, visible parts (the canopy and filters, in the kitchen, quick to wipe and giving the appearance of a clean) while skimping or skipping the hard, hidden parts (the ductwork, needing access and thorough work; the fan, often on the roof) - because those take more time and effort. So a bad clean leaves the crucial hidden parts grease-laden while looking clean from the kitchen. The signs to look for fall into two groups: physical evidence of grease left, and missing documentation. Physical signs: grease left in the hidden parts. (1) Grease at the access panels - the access panels let you (or the cleaner) see into the ductwork. If you open an access panel and find grease still coating the duct inside, the ductwork was not properly cleaned. Clean duct at the panels is a good sign; greasy duct is a clear sign of a bad clean. (2) The fan not cleaned - if the extract fan is still visibly grease-laden, it was skipped. (3) Access panels not opened, or absent - if the access panels show no sign of having been opened (or there are none), the ductwork could not have been reached and cleaned. So the physical signs are grease remaining where it should have been removed, especially in the ductwork and on the fan. Documentation signs: no proof of the whole clean. A proper clean is evidenced - so the absence of evidence is a major red flag. (1) No before-and-after photographs - a good clean provides photographs showing the system (especially the ductwork and fan) before and after cleaning, proving the hidden parts were done. No such photographs (or only photos of the visible canopy) suggests the hidden parts weren't cleaned or can't be shown to have been. (2) No proper report - a good clean provides a report of what was cleaned. (3) No certificate to a recognised standard - a proper clean is certified to TR19 Grease. So the absence of before-and-after photographs of the ductwork and fan, a report, and a certificate are strong signs of a clean that was done badly (or at least can't prove it was done properly). Why it matters. Spotting a bad clean matters because a clean that skimped the ductwork and fan leaves the real fire risk (in those hidden parts) unaddressed - and leaves you with a false sense of a clean, safe system (the visible canopy looking fine) when it isn't. So if you spot these signs, you likely didn't get the whole-system clean you paid for, and the fire risk (and compliance gap) remains - so it's worth challenging the cleaner and, if needed, getting a proper clean. So spot a bad clean by checking for grease left in the hidden parts and the absence of proper photographs and documentation - the tell-tale signs that only the easy parts were done. So the signs are grease left and no proof of the whole clean. This is general commentary on cleaning quality.
Key points
What a bad clean looks like
The key to spotting a bad extraction clean is understanding what one looks like: it does the easy, visible parts while skimping or skipping the hard, hidden parts. The canopy and filters are in the kitchen, visible and relatively quick to clean - so a cleaner cutting corners can clean those (giving the appearance of a clean, since the canopy looks good) while skimping or skipping the ductwork (hidden, needing access and thorough work) and the fan (often on the roof, needing access at height). Those hidden parts take the most time and effort, so they are what a bad clean neglects.
So the result of a bad clean is a system that looks clean from the kitchen (the visible canopy done) but is still grease-laden where it matters (the hidden ductwork and fan) - the very parts that carry the real fire risk. This is why a bad clean can pass at a glance and why you have to look beyond the visible canopy to judge it. The tell-tale signs, accordingly, are found in the hidden parts (is grease still there?) and in the evidence (can the cleaner prove the whole system was done?) - covered in the next sections. So what a bad clean looks like: the easy parts done, the hard parts skimped. So the easy parts done, the hard parts skimped. This is general commentary.
Check the hidden parts
The most direct way to spot a bad clean is to check the hidden parts for grease left behind - because that is exactly what a bad clean leaves. Grease at the access panels: the access panels are openings into the ductwork, so they let you see inside. Open an access panel (or ask the cleaner to) and look at the duct's internal surface: if it is clean, the duct was cleaned; if it is still coated in grease, the ductwork was not properly cleaned - a clear sign of a bad clean. This is the single most useful check, since the ductwork is the main hidden part a bad clean skips.
The fan: if you can see the extract fan (or its housing), check whether it looks cleaned or still grease-laden - a still-greasy fan was skipped. Access panels not opened or absent: if the access panels show no sign of having been opened (undisturbed seals, untouched), the ductwork behind them wasn't reached - so it wasn't cleaned. And if there are no access panels at all, the ductwork couldn't have been cleaned internally (you can't clean what you can't reach). So checking the hidden parts - the ductwork at the access panels, the fan, and whether the access was used - reveals whether the grease was actually removed or left behind. Grease left in the hidden parts is the physical tell-tale of a bad clean. So check the hidden parts - grease left in the ductwork or on the fan. So grease left in the hidden parts is the sign. This is general commentary.
Look for the proof
The other main way to spot a bad clean is by the absence of proper evidence - because a good clean proves it did the whole system, so no proof is a strong red flag. Before-and-after photographs: a proper extraction clean provides photographs showing the system - especially the hidden ductwork and fan - before and after cleaning, proving those hidden parts were actually done (you can see the grease before and the clean surface after). So if there are no before-and-after photographs of the ductwork and fan (only, at best, photos of the visible canopy), that is a strong sign the hidden parts weren't cleaned - or at least can't be shown to have been.
A proper report: a good clean provides a report of what was cleaned (the scope, the system covered) - its absence, or a vague one, is a red flag. A certificate to a recognised standard: a proper clean is certified to TR19 Grease (the recognised standard) - no certificate, or one not to a recognised standard, is a concern. So the documentation should evidence the whole clean: photographs of the hidden parts done, a report, and a TR19 Grease certificate. The absence of this evidence - particularly before-and-after photographs of the ductwork and fan - is a major sign of a clean that was done badly, or at least one you can't verify was done properly. A cleaner who did the whole system properly will have and provide this proof; one who skimped often can't. So look for the proof - before-and-after photographs and documentation. So look for photographs and documentation as proof. This is general commentary.
Why it matters
Spotting a bad clean matters because the consequences of a clean that skimped the hidden parts are serious: the real fire risk remains, and you are left with a false sense of safety. The whole point of extraction cleaning is to remove the grease that is the fire risk - and the greatest fire risk is in the hidden ductwork and on the fan (a grease-laden duct is what a fire spreads through). So a clean that did the visible canopy but skimped the ductwork and fan leaves the real fire risk unaddressed - the dangerous grease still there, in the parts that matter most.
Worse, it leaves you with a false sense of safety: the visible canopy looks clean, you have paid for a 'clean', so you believe the system is clean and safe - when the hidden fire risk is untouched. This false reassurance can be more dangerous than knowing the system is dirty, because it invites complacency. And there is a compliance dimension: without the proper clean and evidence, your fire risk assessment and insurers' expectations aren't really met (a bad clean with no proof doesn't demonstrate the risk is managed). So a bad clean is not a minor shortfall - it leaves the fire risk and a false sense of safety, and fails the compliance purpose. This is why spotting it matters. So why it matters: a bad clean leaves the fire risk and a false sense of safety. So it leaves the fire risk and false reassurance. This is general commentary.
If you spot a bad clean
So if you spot the signs of a bad extraction clean - grease left in the ductwork or on the fan, access panels unopened or absent, no before-and-after photographs of the hidden parts, no proper report or certificate - you likely didn't get the whole-system clean you paid for, and the fire risk remains: so challenge it and get it done properly. First, raise it with the cleaner: point out the grease still in the ductwork or on the fan, or the lack of evidence, and ask them to complete the whole-system clean properly (and provide the photographs and documentation). A reputable cleaner will put it right; a resistant or unable one tells you what you need to know.
If the cleaner won't or can't do it properly, get the whole system cleaned by a competent extraction cleaner who does the whole system to TR19 Grease and provides the proof (photographs of the ductwork and fan, a report, a certificate) - so the fire risk is actually addressed and you have the evidence. And learn for next time: choose a cleaner who does and proves the whole system (as covered in choosing a cleaning company), and check the evidence of each clean (as in auditing the work). So don't let a bad clean stand - it leaves the fire risk and no compliance evidence. Spot it, challenge it, and get a proper whole-system clean. So if you spot a bad clean, challenge it and get it done properly. So challenge it and get it done properly. This is general commentary on cleaning quality.
Questions
Check the hidden parts for grease left behind (especially the ductwork at the access panels and the fan) and look for the absence of proper before-and-after photographs and documentation - the signs a clean did only the visible parts. A bad clean typically does the easy, visible canopy and filters while skimping or skipping the hidden ductwork and fan. So look beyond the visible canopy: open an access panel and check the ductwork inside - if it's still greasy, the duct wasn't cleaned; check the fan for grease; and see whether the access panels were even opened (or exist). Then check the evidence: a proper clean provides before-and-after photographs of the ductwork and fan, a report, and a TR19 Grease certificate - so the absence of these (especially photos of the hidden parts) is a strong sign the whole system wasn't done. So grease left in the hidden parts and no proof of the whole clean are the tell-tale signs. So check the hidden parts and the documentation. This is general commentary.
In the hidden parts a bad clean skips - the ductwork (via the access panels) and the extract fan; grease still there means those parts weren't properly cleaned. The visible canopy is easy to clean and often looks fine even after a bad clean, so it's not where to check. The hidden parts are: the ductwork - open an access panel and look at the internal surface of the duct; clean means it was cleaned, greasy means it wasn't (this is the most useful check, as the ductwork is the main part a bad clean skips); and the fan - check the extract fan (or housing) for grease, since a rooftop fan is often skipped. Also check whether the access panels were opened at all (undisturbed panels mean the duct wasn't reached) or exist (no panels means the duct couldn't be cleaned internally). So check the ductwork at the access panels and the fan - grease there reveals a bad clean. So check the ductwork at the panels and the fan. This is general commentary.
Before-and-after photographs of the whole system (especially the ductwork and fan), a report of what was cleaned, and a certificate to the TR19 Grease standard - the evidence that the whole system was done. A proper extraction clean is evidenced so you can verify (and demonstrate) it was done properly: before-and-after photographs showing the system - crucially the hidden ductwork and fan - before and after cleaning (proving the hidden parts were actually cleaned); a report describing what was cleaned and the scope; and a certificate stating the clean was done to the recognised TR19 Grease standard. This documentation evidences the whole clean (for your own assurance, your fire risk assessment, and insurers). So its absence - particularly no before-and-after photographs of the ductwork and fan - is a red flag that the hidden parts weren't done or can't be shown to have been. A cleaner who did the whole system properly will provide this proof. So a proper clean provides photographs, a report and a TR19 Grease certificate. So photographs, a report and a certificate. This is general commentary.
Because before-and-after photographs are how a clean proves it did the hidden parts (the ductwork and fan) - without them, there's no evidence those parts, which a bad clean skips, were actually cleaned. The hidden parts of the extraction (ductwork, fan) can't be seen from the kitchen, so the way a proper clean proves it cleaned them is with before-and-after photographs - showing the grease before and the clean surface after. These photographs are the evidence that the hidden, important parts were done. So if a clean provides no before-and-after photographs (or only photos of the visible canopy, not the ductwork and fan), there's no proof the hidden parts were cleaned - which, combined with those being exactly what a bad clean skips, makes it a strong red flag. A cleaner who properly cleaned the whole system can readily show the photographs; one who skimped often can't. So no before-and-after photographs of the hidden parts means no proof they were cleaned - a red flag. So it means no proof the hidden parts were done. This is general commentary.
Challenge the cleaner to complete the whole-system clean properly (with proof); if they won't or can't, get a competent cleaner to do the whole system to TR19 Grease - so the fire risk is actually addressed. If you spot the signs of a bad clean (grease left in the ductwork or on the fan, no proof of the hidden parts), raise it with the cleaner: point out the grease still there or the missing evidence, and ask them to complete the whole-system clean properly and provide the photographs and documentation. A reputable cleaner will put it right. If they won't or can't, get the whole system cleaned by a competent extraction cleaner who does the whole system to TR19 Grease and provides the proof - so the fire risk in the hidden parts is actually removed and you have the evidence. And for next time, choose a cleaner who does and proves the whole system, and check the evidence each time. So challenge the bad clean and, if needed, get a proper whole-system clean. So challenge it and get it done properly. This is general commentary.
It's possible a system has some quickly-returning grease or hard-to-remove staining, but genuine signs - fresh grease in the ductwork, an uncleaned fan, no evidence of the hidden parts - indicate a bad clean; the proof (photographs, report) settles it. In fairness, not every imperfection means a bad clean: a system can start re-accumulating light grease soon after a clean (especially with heavy cooking), and some surfaces may have permanent staining that isn't removable grease. So a little residue isn't necessarily proof of a bad clean. But the genuine signs are clear: significant grease still coating the ductwork at the access panels, an obviously uncleaned (grease-laden) fan, access panels never opened, and - decisively - no before-and-after photographs or documentation proving the hidden parts were done. Those indicate a clean that skipped the hard parts. The evidence settles it: a proper clean can show the photographs of the ductwork and fan cleaned. So genuine signs and the absence of proof indicate a bad clean, distinct from minor residue. So the real signs and lack of proof indicate a bad clean. This is general commentary.
A bad clean leaves grease in the hidden ductwork and fan and can't prove the work. We clean the whole system to TR19 Grease and provide the before-and-after photographs, report and certificate that prove the hidden parts were done. Ask us for a whole-system clean you can verify. This is general commentary on cleaning quality.
