At the end of a long service, most kitchens look pretty good. Surfaces wiped, floor mopped, bins out. Job done.

Then an inspector turns up, pulls the fryer away from the wall, shines a torch into the canopy, and suddenly things look a little different.

That's not a sign your team isn't trying. It's just that daily cleaning is designed to get you ready for tomorrow, not to reach every corner of the kitchen. Deep cleaning is what fills that gap, and the areas it covers tend to be exactly the ones that catch restaurants out.

Here are the restaurant cleaning spots missed most often, and what a good deep clean should do about them.

Why the hidden areas matter

Your food hygiene rating isn't just about how the kitchen looks at a glance. Inspectors want to see that restaurant cleaning goes beyond the obvious and that it's being managed properly.

The frustrating part is that one neglected area can undo a lot of good work. A kitchen can be spotless on the surface, but a greasy canopy or a blocked drain is often enough to drag the whole score down. And with ratings displayed on the door and online, that's something customers will see.

1. The extraction canopy and filters

If there's one area to prioritise, it's this one.

Every pan, grill and fryer sends grease into the air, and a lot of it ends up on the canopy, in the filters and further up into the ductwork. The front of the canopy might get a wipe, but the filters and the areas behind them usually don't, and that build-up happens quicker than most people expect.

It's not just a hygiene issue either. Grease in extraction systems is a well-known fire risk, which is why insurers often take a close interest in how regularly it's cleaned.

What a restaurant deep clean should include: a thorough degrease of the canopy inside and out, proper cleaning of the filters, and attention to the grease channels and areas just behind them. Ductwork cleaning is usually specialist work, so it's worth asking any contractor exactly what's covered.

2. Behind and under the cooking line

Ranges, fryers and ovens are heavy, often connected to gas, and usually pushed right up against the wall. Understandably, nobody's moving them at 11pm on a Saturday.

The result is that the floor and wall behind them can go a long time without being touched. Spilt oil, dropped food and baked-on grease all collect there, and it's one of the first places an inspector will look when they want to know how thorough your cleaning really is. It's also a favourite spot for pests.

What a restaurant deep clean should include: carefully moving equipment where it's safe to do so, cleaning the sides and backs of units, and getting the wall and floor behind the line properly clean.

3. Edges, corners and drains

Here's a slightly annoying truth about mopping: it tends to push dirt towards the edges of the room. Over time, that builds up where the floor meets the wall and in the grout lines.

Drains are another common problem. Food waste and grease gather in them, and before long you've got a smell that no amount of surface cleaning seems to shift. If you're noticing little flies around the drains, that's usually a sign they need attention.

What a deep clean should include: scrubbing floor edges and grout, and lifting drain covers to clean out what's built up underneath.

4. Fridges, walk-ins and door seals

Cold rooms can feel clean simply because they're cold, but they still need regular attention.

Door seals are the big one. Mould loves to hide in the folds of the rubber. Fans inside walk-in chillers can gather dust, and the bottoms of shelving units are a magnet for spills that go unnoticed.

What a restaurant deep clean should include: cleaning the shelving, seals and inside surfaces. Stock will need moving while this happens, so it's something to plan ahead with your cleaning team.

5. Everything above head height

Most kitchen cleaning happens from the waist down, which makes sense, because that's where the work happens. But steam and grease rise, and they settle on ceilings, light fittings, pipework and the tops of units.

Over time that becomes a sticky layer that catches dust, and it's not something you want hanging over your prep areas. Inspectors do look up.

What a restaurant deep clean should include: cleaning ceilings (where the surface allows), light fittings, the tops of cupboards and shelving, and any exposed pipes or vents.

6. The wash-up area

The wash-up area sees a lot of dirty items coming through, so it's worth keeping on top of.

The inside of the dishwasher, the space under the sinks and the floor beneath the wash-up equipment are all easy to overlook during a busy week.

What a restaurant deep clean should include: cleaning inside the dishwasher, under and behind the sinks, and the splashbacks and floor around them.

7. Dry stores

Dry stores rarely look dirty, but spilt flour, rice and sugar love to hide under the bottom shelf and in the corners. Unfortunately, pests love finding them there too.

What a restaurant deep clean should include: clearing and cleaning shelves, getting underneath them, and flagging anything that looks like signs of pest activity.

What a deep clean won't fix

It's worth being honest about this one. A deep clean can make your kitchen properly clean, but it can't repair the building. Cracked tiles, peeling paint and damaged surfaces can all affect an inspection too, because they're hard to keep clean.

A good cleaning team won't just clean around these problems. They'll point them out, so you can get them sorted before someone else notices them.

Don't forget the paperwork

Inspectors aren't only interested in whether the kitchen is clean. They also want to see that cleaning is organised. Keeping a simple cleaning schedule, and a note of when deep cleans have taken place, goes a long way towards showing that. Before-and-after photos are a nice bonus.

How often should you deep clean?

It really depends on your kitchen. A busy site that does a lot of frying and grilling will need it more often than a quieter one with a lighter menu. Many restaurants find that every few months works well, but the right answer is the one that stops build-up before it becomes a problem.

A handy way to think about it: if your team can't reach it during close-down, it belongs on the deep-clean list. And if nobody can remember when it was last done, it's probably overdue.

Choosing the right people for the job

Cleaning a restaurant kitchen is a very different job from cleaning an office. It takes the right products, the right equipment, and a team that understands what inspectors look for. It also needs people who are happy to work overnight or on your closed days, so the kitchen's ready for the morning and you never lose a service.

Got an inspection on your mind? Templetons Cleaning Services provides restaurant deep cleaning across London, working around your opening hours so service is never disrupted.