Three duct types
There's no TR19-style table for laundry ducting. Lint filters clear every cycle; the duct itself is cleaned on a risk-based interval set by how hard you run - and the machines warn you.
The short answer
Unlike kitchen grease ductwork, laundry and tumble-dryer ducting has no single standardised matrix. Lint filters should be emptied every cycle, and the ducting itself cleaned on a risk-based schedule set by how much you run: light use might need the full duct cleared a couple of times a year, while a busy commercial laundry needs it far more often. Build-up rate, not a table, sets the interval.
Why there is no matrix
Grease accumulates in step with cooking hours, which is why it can be scheduled from a table. Lint is less obliging. How fast it builds depends on load volume, the fabrics you dry, the length and layout of the duct run, and how many hours the machines run - variables that differ so much between sites that no single national interval would fit them all. So laundry ducting is cleaned on a risk-assessed basis: you judge the build-up rate for your operation and set the interval to keep ahead of it.
That starts with the basics done relentlessly. The lint filter is the first line of defence and should be cleared every cycle, not every day - a blocked filter pushes lint straight past into the duct, accelerating the very build-up you are trying to control.
Setting the interval
The heavier the laundry operation, the shorter the interval. A small in-house laundry running a couple of loads a day is a different risk from a hotel, care home or industrial laundry running dryers almost continuously - the latter needs the full exhaust duct cleared much more frequently, alongside removal of fluff from around, under and behind the machines where it collects. As a rule, set the cadence by inspection and build-up rather than by the calendar alone.
The machines will also warn you when the interval is too long. Loads taking longer to dry, laundry coming out hotter than usual at the end of a cycle, or a burning smell all point to a restricted, lint-loaded duct - and mean the clean is overdue, whatever the schedule said.
Getting it right
The practical approach mirrors the grease logic without the fixed bands: assess your laundry's volume and duct layout, set a starting interval, then adjust it against what inspections and the warning signs tell you. A high-volume commercial laundry should treat full-length duct cleaning as a routine, scheduled task, not something done only when a problem appears - because by the time lint has restricted the duct enough to notice, the fire risk is already elevated.
So the honest answer to how often a laundry duct needs cleaning is: as often as your build-up demands - which is exactly why it is assessed, not tabulated, and why keeping ahead of the lint is the whole game.
Questions
There is no fixed matrix. Lint filters should be emptied every cycle, and the duct itself cleaned on a risk-based interval - a couple of times a year for light use, far more often for busy commercial laundries.
Because lint build-up depends on load volume, fabric type, duct layout and run hours - variables that differ too much between sites for a single national table to fit. So laundry ducting is cleaned on a risk-assessed basis.
Watch the machines: loads taking longer to dry, laundry coming out hotter than usual at the end of a cycle, or a burning smell all point to a restricted, lint-loaded duct that needs clearing now.
Yes. High-volume operations running dryers near-continuously need the full exhaust duct cleared much more frequently, plus removal of fluff from around, under and behind the machines.
No. The filter is the first line of defence and must be cleared every cycle, but lint still passes into the duct, which needs its own scheduled cleaning to atmosphere.
Phoenix Duct Clean · by the numbers
We assess your laundry, set a risk-based schedule and clear the full exhaust duct to atmosphere. Book a laundry duct assessment.