A commercial kitchen accumulates grease faster than any domestic space, and the consequences of letting it build are more serious. Grease in extraction ductwork is a genuine fire risk, and insurers routinely ask for evidence that it is managed.
The other driver is inspection. Food hygiene ratings look at structural cleanliness as well as day-to-day practice, and the areas that pull ratings down are usually the ones a nightly clean never reaches.
The short version
- Extraction canopies and ductwork are a fire risk, not just a cleaning task
- Behind and under equipment is what inspections focus on
- Deep cleaning needs to be documented, with dates and areas covered
- Schedule around service, usually overnight or on closure days
- Floors and drainage cause more slip incidents than anything else
Why grease matters more here
Cooking produces aerosolised fat that is drawn into the extraction system and condenses on every internal surface it passes. Over months it forms a thick, combustible layer inside the canopy, filters and duct run.
That is why extraction cleaning is treated separately from general kitchen cleaning and why insurers frequently require certificated evidence of it. It is also why filter cleaning on a short cycle matters: filters that are kept clean reduce how much grease reaches the ductwork in the first place.
What a deep clean covers
The distinguishing feature is that equipment gets moved and dismantled. A nightly clean addresses the working surfaces; a deep clean addresses what is behind, under and inside them.
- Behind and beneath fryers, ranges, grills and fridges
- Canopy interiors, filters and accessible duct sections
- Wall and ceiling surfaces, including above head height
- Shelving, racking, and the underside of prep benches
- Floor drainage, gullies and the coving where floor meets wall
- Cold room and fridge interiors, seals and door furniture
Frequency by area
Different parts of a kitchen soil at very different rates, and applying one frequency to everything either wastes money or leaves risk in place.
Filters and the immediate cook line need frequent attention. Duct runs and high-level surfaces are periodic. Structural areas like ceilings and wall junctions are typically scheduled a couple of times a year, more in a high-volume kitchen.
- Canopy filters: weekly or more often in high-volume kitchens
- Cook line, behind and under equipment: monthly to quarterly
- Canopy interior and accessible duct: periodically, per risk assessment
- Walls, ceilings, shelving and cold rooms: quarterly to biannually
Floors, slips and drainage
Commercial kitchen floors carry a film of grease and water that ordinary mopping spreads rather than removes. A mop and bucket dilutes the film and redistributes it, which is why floors can look clean and still be slippery.
Deep cleaning a kitchen floor means a degreaser with dwell time, mechanical agitation of the surface and the grout lines, and then extraction or a wet vacuum to remove the solution rather than letting it dry back. Gullies, channels and coving need doing at the same time.
Scheduling around service
Deep cleaning happens when the kitchen is not in use, which usually means overnight or on a closure day. That needs planning: access, key holding, alarm arrangements and someone to sign off at the end.
The practical approach is to agree a rolling programme so different zones are covered at appropriate intervals without ever taking the whole kitchen out of action for long.
- Agree access, keys and alarm procedure in advance
- Confirm which equipment can be isolated and by whom
- Allow drying time before service resumes
- Get a signed record of areas covered on each visit
Records and evidence
Documentation is part of the deliverable. A dated record of what was cleaned, by whom, and with which products supports both food safety management and insurance requirements.
Keep the records with your food safety documentation rather than filing them separately. When an inspector asks how structural cleaning is managed, having the schedule and the completed records to hand answers the question immediately.