“Not that one.”

It comes at the doorway, usually about forty minutes in, and it comes with a small apologetic laugh or with nothing at all. Sometimes the door has a chair in front of it. Sometimes there is a note. Once, in a maisonette off Landells Road in East Dulwich, there was a bolt on the outside and a bag of bedding beside it that nobody explained and nobody was going to.

The professional answer is short. The door stays shut, it does not get mentioned again, and the job carries on. What follows is why that is the right answer, and what happens on the days when it is not enough.

Why does nearly every house have one?

Because the reasons are so ordinary that nobody thinks to name them, and the customer assumes their reason is stranger than it is.

The commonest by a mile is a teenager who has negotiated their own terms with their parents and won. Second is a home office with client papers, medical records, or a laptop that belongs to an employer with rules about who is in the room with it. Third is storage, meaning a spare room that became a garage some time in 2019 and has not been faced since. Fourth is a lodger or an adult child paying rent, whose room is legally and practically not the person’s to hand over.

Then the ones people go quiet about. A room belonging to somebody who has died, kept as it was. A partner going through treatment who is asleep at eleven in the morning. A room the customer is ashamed of, which is its own category and the biggest of the quiet ones.

The reason is rarely the one you assume

Cleaners get this wrong constantly and in a specific direction. The closed door reads as suspicion. Somebody thinks I will steal something, somebody has been told to keep an eye on me, somebody does not trust me in there.

In eleven years the number of times a closed room turned out to be about distrust of the cleaner is very small. It is nearly always about the customer, and it is nearly always shame or grief or a domestic negotiation that has nothing to do with the person holding the mop. Assume otherwise and you get a defensive cleaner, and defensive cleaners ask questions they should not ask.

What should you do when the instruction is vague?

Make it specific once, in a flat voice, and then never raise it again.

There is a real difference between “leave that room”, “do the floor but nothing else”, “the door stays shut and please do not open it even to look”, and “clean it when he’s out”. Those four instructions produce four different jobs and three of them can go wrong if the cleaner guesses. The question to ask is practical and takes eight seconds: do you want that door left closed entirely, or is there anything in there you would like done?

Ask it while writing rather than while standing in the doorway. It reads as admin instead of curiosity, and it gives the customer an easy way to say very little.

What goes on the job sheet

Write it down, in the customer’s words where possible, and keep it with the booking rather than in somebody’s head.

Three lines is enough. Which room. What the instruction is. Who gave it. That last one matters more than it sounds in shared households, because an instruction from one of four tenants in a house on Sumatra Road in West Hampstead is not the same as an instruction from the person paying the invoice, and the difference will surface eventually.

Then it transfers. Cleaners are ill, cleaners leave, and the person covering on a Thursday has no idea about the second bedroom unless somebody wrote it down. A regular customer should never have to explain the closed door twice.

Where does the awkwardness come from?

From two directions at once, and they feed each other.

On the customer’s side it is exposure. There is something odd about the whole transaction of letting a stranger into your home. Most people tidy before the cleaner arrives, which is a joke everybody makes and a real behaviour that tells you exactly how it feels. A closed room is usually the part of the house the person has not managed to make presentable, and being asked about it, even kindly, even once, lands as being caught.

On the cleaner’s side it is liability. A room nobody enters is a room where anything could be reported missing later, and the accusation costs a livelihood whether or not it holds up. That fear is legitimate and it drives some bad practice, chiefly cleaners who insist on entering rooms they have been asked to leave, because they would rather have seen the state of it.

The way through is procedural rather than emotional. The door stays shut and the arrangement is recorded, so that if a question arises in six months there is a written instruction with a date on it. Nobody has to remember who said what. That protects the cleaner considerably better than a quick look round the door ever would.

The accusation that never quite happens

Something goes missing in a house roughly once every couple of years, and in every instance I can recall it turned up. A ring in a coat pocket. Two hundred pounds in a book. A passport in a drawer somebody had already searched twice.

What matters is the hour between the phone call and the discovery, and the only thing that gets a cleaning firm through that hour with a relationship intact is having been boring and documented from the start. Which rooms were entered. When. By whom. A closed room on a job sheet is a fact rather than a memory, and it takes an entire category of accusation off the table before it starts.

Insist on that in writing even when the customer waves it away as unnecessary. Especially then.

When should a cleaner say something, and when should they say nothing?

Nothing, almost always. There are narrow exceptions and they are worth being clear about, because the alternative is a lot of well-meant intrusion that helps nobody.

A cleaner is not qualified to assess anyone’s mental health, and a closed door is not evidence of anything. Someone keeping a room shut is exercising a normal preference in their own home. The default is respect and silence, and the customer is entitled to a service without an inquiry attached to it.

The exceptions are physical and specific. A blocked exit or a stairway that cannot be used in a fire. A smell that suggests a leak, a dead animal, or spoiled food in quantity. Visible signs that someone in the household is not managing and might welcome practical help. In those cases the thing to do is say it once, plainly, to the person who booked the job, without a diagnosis attached and without a second attempt if the answer is no.

Say what you saw, not what you concluded. “The landing cupboard has water coming from it” is useful. “I think you might have a problem” is not, and it ends the working relationship without helping anybody. If the person opens up and wants suggestions, GPs, local authority adult social care teams and specialist clearance firms exist and a cleaner can name them. That is the whole of the appropriate role.

The firms selling hoarding cleans

This is the part of the trade I have least patience with. Hoarding is a recognised condition and the clearance work around it needs training, a relationship with the person, a proper risk assessment and usually a professional coordinating it. There is a whole industry of general cleaning companies advertising hoarding services with a van and no training whatsoever.

What those jobs produce is a house cleared in a day against somebody’s will, a person in acute distress, and a relapse that is worse than the starting point. Turn the work down. A domestic cleaning firm that says no to that booking and passes on a specialist’s number has done more good than one that says yes.

How do you price and schedule around a closed room?

By adjusting the quote rather than pretending nothing changed.

Hourly work handles itself. Fixed-price quotes should be built on rooms cleaned, not rooms in the property, and a three-bed where one bedroom is permanently closed is a two-bed job with a slightly awkward landing. Charge for a room nobody enters and it gets discovered eventually, and it costs the account.

The scheduling point matters too. A closed room takes time off the visit, and the sensible move is to put that time somewhere useful rather than banking it. Offer it to the kitchen, or to the skirtings, or to the oven that has been on the list since March. Customers notice when unused time goes back into the house and they notice when it does not.

When the door opens

Sometimes it does. A tenant on Approach Road in Bethnal Green kept a second bedroom closed for two years and then asked, in the middle of an ordinary conversation about bin days, whether it could be included from next month.

Say yes without ceremony. No comment on the state of it, no observation about how long it has been, no relief expressed. Quote for it the way you would quote for any room, add the extra time, and clean it exactly as well as everything else. The customer has spent months deciding to ask and the worst possible response is any response at all.

A house on Coningham Road in Shepherd’s Bush has had the same instruction on the sheet for five years. Front bedroom, left alone, door pulled to on the way past.

Run a fingernail down the door, somewhere in the middle of the panel, and look at the nail.

If there is a soft brownish smear on it and the door underneath has a clean track where the nail went, that is grease and it can be dealt with. If the nail leaves a mark but takes nothing off, and the yellow is uniform across the whole panel and stops dead at the edge banding, the door is going. Those two things get confused constantly, they get charged for identically, and only one of them responds to anything a cleaner brings in the van.

How do you tell one from the other?

Location tells you most of it before you touch anything.

Grease has a geography. It is heaviest on the doors within about a metre of the hob, worse on the wall units than the base units because warm air rises, and worst on the door faces angled toward the pan rather than away from it. The corner unit at the far end of a galley kitchen will be noticeably cleaner than the one beside the extractor. Finish failure has no gradient like that, or it has one that runs the other way, along heat and light sources rather than out from the cooker.

Colour differs too. Grease film reads brown-amber and sits on top of a white that is still white underneath. Failed white lacquer or a degraded foil reads creamy, ivory, sometimes faintly pink, and it goes right through, which is why the inside face of the door still looks factory-fresh while the outside has aged a decade.

What the edges tell you

Look at the top edge of a wall unit door and the vertical edge nearest the dishwasher.

On a vinyl-wrapped MDF door, the wrap is a single sheet of PVC foil pressed over the front and folded round to a seam on the back. That seam is the weak point, and steam gets into it. Once it lifts, you get a fingernail-width of exposed MDF along one edge, sometimes swollen. That is a door past saving, whatever the front looks like.

On a lacquered or two-pack sprayed door, the edges stay sound and the flat of the panel yellows. On a laminate door, neither happens and the problem is nearly always grease.

What makes a finish yellow on its own?

Three separate mechanisms, and it pays to know which one you have, because two of them are somebody’s fault and one of them is nobody’s.

Heat is the commonest. PVC foil is thermoplastic, which means it softens and moves at temperatures a kitchen produces routinely. A door mounted immediately beside a built-in oven, particularly above a pyrolytic one, gets a slow cooking of its own every time the oven runs. The foil discolours, shrinks slightly, and pulls away at the nearest edge. A kitchen on Ermine Road in Lewisham had a housing unit where the two doors flanking the oven were visibly creamier than the eight identical doors elsewhere in the run, and the fitter had left no heat gap at all.

Light is the second. White finishes yellow under UV, and the ones that yellow fastest are the cheap solvent-based lacquers and older polyurethane systems. In a kitchen with a south-facing window or a set of bifolds, the doors nearest the glass will run ahead of the rest. Take a door off and hold it against one from the far end of the room and the difference is obvious, which is a test worth doing before anyone pays for a deep clean.

Third, and the one people find hardest to believe: the finish leaching its own softeners out. PVC foil contains plasticisers to keep it flexible, and over ten or fifteen years those migrate to the surface and sit there as a faintly tacky, faintly yellow layer. It feels exactly like grease. It wipes away and comes back within a week, because the source is inside the material rather than on it. Nothing stops it. A house in Pinner had this on every door of a kitchen fitted in 2009, and three cleans in eighteen months achieved nothing except a slow flattening of the sheen.

The door beside the oven

Take that one off its hinges and look at the back.

Heat damage shows there first: a faint scorch shadow, a foil edge lifting on the hinge side, sometimes a soft ripple in the surface where the board underneath has moved. A door that shows any of that is past saving and the rest of the kitchen probably has years left. Two replacement doors from the original supplier cost a fraction of a new kitchen and most people never consider it.

If it is grease, why is it sticky rather than oily?

Because it has been there long enough to stop behaving like oil.

Fresh cooking splatter is wet and comes off with washing-up liquid. Old deposit has oxidised into something tacky that grabs dust, and the dust is a large part of what makes the film look grey-brown rather than yellow. That is the whole explanation and it does not need more than that.

What removes it

An alkaline degreaser, applied warm, given four or five minutes to sit rather than sprayed and wiped, worked with a soft pad, and rinsed off with clean water on a separate cloth. The rinse is the part everyone skips and it is the part that decides whether the door stays clean or turns tacky again in a fortnight.

Do a test patch on the inside of a door first, always, because some finishes will not take an alkaline product. Matt lacquers in particular go patchy and there is no way back from that.

Budget about ninety seconds a door for the wipe and rinse on a wall unit, and more like three minutes on a base unit door beside the hob, where the deposit is thicker and the handle area needs separate attention. A run of eighteen doors is most of a morning done properly, which is why it gets skipped on a standard visit and why the film keeps building until somebody notices the colour.

What makes the problem worse?

Almost everything sold to fix it in a hurry.

Melamine foam pads are the worst thing in domestic cleaning and I will argue about it with anybody. They are a fine abrasive. What they do to a gloss door is remove the top few microns of the finish along with the marks, which looks like a triumph on the day and leaves a dull, slightly rough patch that then holds dirt faster than the surrounding surface. Six months later the door has a permanent cloudy oval where somebody was thorough. On a foil-wrapped door they can go through the print layer completely and take the wood-grain pattern off.

Solvents come next. Acetone, white spirit, nail varnish remover, and the citrus degreasers people reach for when the ordinary spray fails. All of them will soften PVC foil and several will lift lacquer. A tenant on Fentiman Road in Oval took the sheen off four doors in one afternoon with a solvent wipe intended for oven interiors.

Bleach does nothing useful on grease, and on a yellowed finish it does nothing at all, because the yellowing is not a stain. It is the material. People keep trying, and what they end up with is a door that is both past saving and faintly smelling of chlorine.

Then heat. Steam cleaners get pointed at kitchen doors constantly and they are a poor idea on anything wrapped, since the steam goes straight into the back seam and starts the delamination that was going to take another five years to arrive on its own.

The scouring pad question

Green scourers, wire wool and gritty cream cleaners belong on a pan and nowhere near a cupboard door. The one exception is a true laminate face, which is hard enough to take a cream cleaner on a bad mark, and even then a test patch first.

When is a door past saving, and what then?

When the yellowing is in the material rather than on it, and no clean is going to change that.

The options are narrower than people expect. Doors from a mainstream range fitted in the last decade can often be reordered individually, which is the cheapest answer by a distance if you can identify the range. Photograph a hinge plate, the back of a door, and any label inside a carcass, and a kitchen showroom will usually tell you what you have. A homeowner near Canbury Park Road in Kingston replaced eleven doors on a fifteen-year-old carcass run for less than a fifth of what three quotes for a new kitchen came to.

Spray refinishing is the second option, and it works properly on solid or MDF doors with a sound substrate. On a wrapped door it is a waste, because the wrap is the problem and paint over a lifting foil lifts with it.

Refoiling exists. At London labour rates it is rarely worth the money, and the finish is seldom as good as the factory one it replaces.

What to ask before anyone quotes

Ask whether the doors are foil-wrapped, sprayed, or laminate, and get the answer from somebody who has taken one off rather than looked at it. Ask what the heat gap beside the oven housing is, because if the original fitter left none, new doors will do exactly the same thing.

And ask whether the extractor works, since a hood that has not moved air properly in years is the reason the far doors are yellow as well as the near ones.

The doors in Chingford went back on with a two-millimetre packer beside the oven and a new carbon filter in the hood. Eight months, no change to the colour.

Old frying oil, mostly. Turmeric and cumin sometimes, fish sometimes, and underneath a fair number of them a base note of cigarettes that nobody mentioned during the viewing. It hits you at the top of the stairs before you have the door open, it fades after ten minutes because your nose stops reporting it, and it comes back the moment a friend walks in and pauses half a second too long in the hallway.

Two cleans have been paid for. The flat looks immaculate. The smell is still there, and the reason is that almost nothing that produces it lives on the surfaces a clean touches.

What is the smell made of?

Cooking odour is not a vapour hanging in a room. If it were, opening a window for a day would end it, which is what every letting agent in London tells tenants to do and it never works.

What is in the air during cooking is an aerosol: microscopic droplets of oil carrying dissolved volatile compounds, thrown off a hot pan and moved around the flat by convection. Those droplets land. They land on everything, including surfaces four rooms away, and they land in a layer so thin that nobody sees it accumulate. Over three years of daily cooking in a small flat, that layer becomes a continuous film on every wall, ceiling and door in the property.

The volatile part of it evaporates slowly out of that film for years. That is the smell. The film is the reservoir, the room is the delivery system, and cleaning the visible surfaces removes maybe a fifth of the total.

Why cooking oil behaves differently from other odours

Oil oxidises and polymerises. Left on a warm surface with air across it, unsaturated cooking oil cross-links into something closer to a soft varnish, which is the same process that seasons a cast iron pan and the same one that makes a neglected extractor hood sticky rather than greasy.

That matters because a polymerised film does not dissolve in the way fresh grease does. Warm soapy water takes fresh splatter off a wall. It slides straight over a three-year-old film and leaves it there, slightly shinier than before. A cleaner working at normal pace on a normal domestic rate will do exactly that, twice, and the customer will watch a spotless cloth come off the wall and conclude the wall is clean.

Tobacco tar behaves the same way and worse, because it is stickier and it carries nicotine, which is water-soluble and keeps releasing whenever the air gets humid. On a warm day in a flat above a shop on Osbaldeston Road in Stamford Hill you could smell a smoker who had moved out in February.

Where is the smell held?

Six places, in rough order of how much they contribute.

Walls and ceilings hold the most, by sheer area. A one-bed flat has something like ninety square metres of painted surface and all of it has been collecting aerosol. The ceiling directly above the hob is the worst square metre in the property and it is the one nobody cleans, because it is above head height and looks fine from below. Matt emulsion is porous and takes the film into the paint rather than onto it, which is why washing it does very little.

Kitchen unit interiors are next. The inside of a wall cupboard directly beside a hob gets a share of every meal cooked, and chipboard carcasses with a thin melamine face absorb through the exposed edges and the drilled holes. Open one on a warm day a month after the flat was cleaned and the previous tenant is still in there.

Extract ducting third, and it deserves its own paragraph below.

Soft furnishings and carpet fourth. Underlay is the sleeper here: the carpet gets cleaned, the underlay is never touched, and it has been absorbing for years through a permeable backing. A rental in Wellmeadow Road in Catford had two carpet cleans in six weeks and smelled worse after the second, because hot water extraction rewetted an underlay that then took nine days to dry.

Fifth, the loft hatch and any service voids, which hold air that has been moving up out of the kitchen for years.

Sixth, and last, the surfaces a cleaner gets booked to clean.

The extractor duct

Almost nobody looks in it. A recirculating hood in a flat with no external duct has a metal grease filter and a carbon cartridge, and both should be treated as consumables. The carbon in a flat where somebody fried daily is finished within months, and after that the hood pushes odour-laden air back into the room at speed.

A ducted hood is a different problem. The flexible aluminium duct running through a kitchen ceiling void to a soffit vent is corrugated, which means several hundred small ridges each holding a ring of polymerised grease. Switch that fan on and the airflow drags odour off the whole length of it. A flat on Gaskarth Road in Balham smelled of fish only when the extractor ran, which took two visits to work out and about eleven minutes to fix once the duct came off.

Why did two cleans not fix it?

Wrong scope, wrong chemistry, and in a lot of cases the wrong instruction from whoever booked it.

Scope first. A standard end-of-tenancy clean covers surfaces, appliances, floors and sanitaryware. It does not include washing down ninety square metres of wall and ceiling, and it should not, because that is half a day on its own and it is not what the price covers. Anyone who books a tenancy clean and expects a smell to leave with it has bought the wrong service, and the honest thing is to say so before taking the booking rather than after the second one.

Chemistry second. Grease films need an alkaline degreaser with real dwell time, applied warm, worked with a pad, and rinsed with clean water so the emulsified grease leaves the building rather than being spread. Most general-purpose sprays are pH-neutral surfactants designed to be safe on everything, and safe on everything means weak on grease.

Third, and this is where people waste the most money: masking. A flat sprayed with fragrance smells of fragrance plus old cooking, which is a distinctly worse smell than old cooking alone, and everyone recognises it as a cover-up. The plug-in in the hallway of a viewing flat is doing the property no favours at all.

What ozone and fogging are worth

Less than the invoices suggest. Ozone generators do break down odour compounds, and in a fire-damage or heavy tobacco situation a properly run treatment by someone with the right kit has a place. In a normal flat with a cooking smell, it is being sold as a shortcut around the degreasing work and it does not do that, because ozone does not remove a grease film. It alters the top layer of it. Six weeks later, on a warm day, the smell is back.

Ozone also needs the property empty of people, pets and plants during treatment and ventilated afterwards, and plenty of the operators offering it locally treat that as optional. That alone is reason enough to be sceptical of the cheap end of the market.

What shifts it?

Sequence matters more than product, and doing these in the wrong order means doing them twice.

Strip the source first. Filters out and replaced, hood degreased inside, ducting removed and cleaned or renewed, cooker pulled out, kickboards off. Then wash down hard surfaces with an alkaline degreaser: walls, ceilings, doors, frames, the inside of every cupboard, rinsing as you go. Then deal with textiles, which for a rental usually means the curtains go to a cleaner or in a bin, and the carpet gets lifted so the underlay can be assessed rather than cleaned.

Then ventilate properly, which means cross-ventilation with the heating on for several days, not a window on the latch. Warm air holds more and moves more.

Only after all that does sealing make sense. A stain-blocking primer, shellac-based or a modern water-based equivalent, locks in whatever is left in the plaster, and two coats of emulsion over the top finish it. Do that before the degreasing and you have sealed grease under paint, which will bleed through and smell whenever the room warms up.

The thing that loses me the work

Most flats in this state need a painter more than they need a third clean.

Once the film has gone into matt emulsion in a kitchen, the fastest and cheapest permanent answer is one day of degreasing followed by a stain block and a repaint. The clean is a necessary step and it is not the expensive part. A landlord in Lincoln Road in Enfield spent four hundred pounds across three cleaning visits over two months before painting the kitchen and hallway for two hundred and thirty, and the smell went the same week.

When should you stop buying cleans?

After the second one, if the smell is unchanged.

Two proper attempts is enough to establish that the reservoir is somewhere a cleaner cannot reach. At that point the money goes to a decorator, a carpet fitter for underlay, or a plumber and electrician for a hood and duct that should have been replaced when the last tenant left.

If you are renting, put it to the agent in writing before you move in rather than after, and be specific: the ceiling above the hob, the duct, the underlay, the cupboard interiors. General complaints about a smell get a general answer about ventilation. Name the four things and you get a decorator.

What to ask for before you sign

Ask when the kitchen was last painted and whether it was stain-blocked. Ask whether the extractor is ducted or recirculating, and if recirculating, when the carbon filter was last changed. Ask whether the carpet underlay is original.

Three questions, and the answers tell you whether the smell is a two-hundred-pound problem or a nine-hundred-pound one.

The tenant in Acton took the curtains down on the first afternoon and put them in the communal bin. She said the flat improved by about a third before anyone touched a wall.

Four or five enquiries a week come in about black spotting, and three of those are jobs that should not be taken. The customer wants the spots gone. The spots will go, for a while, and then they will come back in exactly the same corner of exactly the same window, and the customer will conclude that the cleaner was no good rather than that the problem was never a cleaning problem.

So here is the split, bluntly. Some of this responds to cleaning permanently. Some responds temporarily. Some will not respond at all, and no product on any shelf in any wholesaler changes that.

What are the black spots?

Mould. Specifically the group of dark moulds that colonise damp surfaces indoors, and in a London flat the usual suspect is Cladosporium, with Aspergillus turning up in worse cases and Stachybotrys on anything that has been wet for months rather than damp overnight.

What matters is not the species. What matters is that these are living organisms with root structures, and they grow into porous or semi-porous material rather than sitting on top of it the way soil does. That distinction decides everything about whether cleaning works.

Spores are in the air of every building in the country at all times. They do nothing until they find a surface that stays above roughly eighty per cent relative humidity for long enough, at a temperature the organism likes, with something to eat. Indoors in winter, all three conditions turn up in the same places: the bottom corner of a window reveal, the sill, the bead of silicone where a bath meets a tiled wall, and the grout line nearest the shower head.

Why sills and silicone rather than anywhere else

Cold surfaces and dead air. A window sill is the coldest horizontal surface in the room, air moving across it slows to nothing in the reveal corners, and moisture condenses out of the air onto the glass and runs down. Whatever film of dust, skin and cooking residue sits on that sill is food.

Silicone is worse, and the reason surprises people. Cured silicone itself is not much of a meal, but sanitary sealant contains plasticisers and fungicidal additives, and the fungicide has a life of two to four years before it leaches out. Once it has gone, the sealant is a soft, slightly porous strip permanently within a few millimetres of standing water, holding soap residue, body oil and shampoo. Mould grows into it, not on it.

A bathroom in a converted house on Bushey Hill Road in Camberwell had sealant so far gone that a fingernail took a strip off the surface with black threading right through the depth of it. Nothing was going to clean that.

What does cleaning fix?

Everything that has not yet penetrated, which is more than people assume if they act early.

Fresh spotting on glass, on tiles, on gloss-painted timber, on plastic uPVC frames and on ceramic comes off completely and stays off, provided the surface is sound. Those materials are non-porous. The mould has nowhere to root, so it is sitting on a film of grime and it lifts with the film. A thorough clean, a rinse, and a dry surface afterwards will hold for months.

Grout responds well if the glaze on the tile is intact and the grout is not crumbling. Cement grout is porous, so the mould has got a few millimetres in, but the material is hard enough that a fungicidal wash with proper dwell time will kill the growth through the depth and the discolouration will lift with a stiff nylon brush. Nine times out of ten, grout that looks ruined is grout that has never had anything left on it for longer than thirty seconds.

Painted plaster is the borderline case. Modern vinyl emulsion is effectively a plastic film, so surface growth wipes off. What it also does is trap moisture in the plaster behind it, which is why the paint often blisters slightly around the spotting. Once the paint has gone, the plaster is porous and the answer changes.

The bleach question

Household bleach on silicone is theatre. It bleaches the pigment in the mould, the black disappears within minutes, the customer is delighted, and the organism is still alive inside the sealant with its colour removed. Three weeks later it darkens again and everybody blames the cleaner.

Two things work better. A thickened chlorine gel that stays in contact with the bead for four to six hours will penetrate far enough to kill rather than bleach, and that dwell time is the whole mechanism. Or a fungicidal wash with a quaternary ammonium base, left wet, wiped, and reapplied and left to dry without rinsing, so a residual film stays behind.

Never mix chlorine products with anything acidic, including limescale removers, which is a genuine hazard in a bathroom where both bottles live under the same sink.

What will cleaning not fix?

Anything where the growth has gone into the substrate, and anything where the substrate itself has failed.

Timber sills are the clearest example. A painted softwood sill in an original sash window has usually had six or seven coats over a hundred and twenty years, and the black in the corner is often growing under the paint film in wet timber rather than on top of it. Cleaning the surface removes the visible part and leaves the colony. Worse, the presence of that growth is a sign that water is getting in past the paint or past the putty, and until someone deals with the putty line, the water keeps arriving.

A ground-floor flat on Estreham Road in Streatham had spotting along the whole front of a bay sill that returned within five weeks of every clean. The putty had gone brittle on the outside face and the sill was wet from behind. Two years of cleaning and repainting did nothing at all.

Failed sealant is the same story. Once the fungicide has leached out and the surface has gone soft or the bead has parted from the tile at the top edge, water is running behind it. The black visible along the front is a fraction of what is in there. Cut it out with a hooked blade, clean the substrate, dry it for twenty-four hours and run a fresh bead of proper sanitary sealant. Forty minutes, and permanent for another three or four years. Cleaning it is a twenty-minute job that lasts a month.

Crumbling grout, blown plaster, and anything with a cold bridge behind it belong in the same category. A room in a hard-to-treat solid-wall property on Coniston Road in Muswell Hill had recurring black in one corner of a bedroom ceiling, and the cause was a steel lintel above the window transferring cold straight through the wall. Every winter, the same corner.

How to tell when silicone has to come out

Press it with a thumbnail. Sound sealant is firm and springs back. Failed sealant compresses and stays compressed, or a nail lifts a skin off it.

Then look at the top edge where it meets the tile. A hairline gap there means water has been going behind for months, and whatever is growing in that gap is not reachable by anything applied to the front. Both of those signs mean replacement, and any cleaner who says otherwise is selling a return visit.

Why does it come back in the same spot every winter?

Because the spot is the coldest square foot in the room, and cleaning does nothing to the temperature.

Condensation forms where the surface temperature drops below the dew point of the air in the room. In a London flat in January that means window reveals, the reveal corner behind a curtain, the wall behind a wardrobe on an external wall, and the ceiling corner where a bay roof meets the main wall. Air with a lot of moisture in it, which is what a flat produces from cooking, showering, drying laundry indoors and two people breathing, will drop that moisture out at the first cold surface it meets.

Cleaning removes the colony. It does not change the dew point, the surface temperature, or the moisture load. Nine times out of ten, recurrence in the same location is a building performance question wearing a cleaning problem’s clothes.

The extractor fan and the window

Most bathroom fans in London flats are the minimum-spec unit wired to the light switch with no overrun, or with a three-minute overrun that stops long before the room has dried. A shower puts something like a litre of water into the air. Three minutes of a weak axial fan removes a fraction of it, and the rest goes into the walls, the ceiling and the sealant.

A humidistat fan with a fifteen-minute overrun, or a decent centrifugal unit in a flat with a long duct run, changes the room more than any cleaning schedule will. Opening the window for twenty minutes with the door shut does nearly as much and costs nothing.

When should you stop cleaning and call someone else?

When it has come back twice in the same place after a proper clean.

At that point the money is better spent on a plumber, a glazier, a damp surveyor or an electrician than on a third visit from me. I will say so on the phone. A flat on Faraday Avenue in Sidcup had three cleans booked for a bathroom ceiling before anyone checked the loft above it and found an uninsulated section directly over the shower.

The landlord and tenant version of this argument annoys me from both directions. the cause is usually the way the property is being lived in, and the remedy is almost always the landlord’s. Drying washing on radiators in a sealed flat produces the moisture. A fan that works and a bit of insulation deals with it. Telling a tenant to open windows more in a January in a flat on Mafeking Avenue in Forest Gate is a repair being dressed up as advice.

What to write down before you complain or before you quote

Photograph the spot with something in frame for scale and note the date. Do it again after the next clean, and again six weeks later. Two dated photographs showing the same corner in the same state are worth more than any amount of description, whether the conversation is with a landlord, a managing agent or an insurer.

Note what is on the other side of the wall as well. Nine times out of ten the answer explains the pattern: an external corner, an unheated hallway, a loft with a gap in the insulation, a shower on the far side of a stud.

The sealant in Camberwell got cut out and replaced. It has stayed white since March, which proves nothing yet.

Yes. With two conditions attached, and neither of them involves paying me more money.

The question comes up constantly since half of London started working from a spare bedroom, and it usually arrives phrased as a suspicion that the customer is being cheap. A couple in a first-floor conversion on Perrymead Street in Fulham asked it about a labrador and a home office, having already half-decided they needed weekly and wanted permission. They did not need weekly. What they needed was to stop hoovering the hall six times a week and start dealing with the sofa.

What does a dog and full-time occupancy add to the load?

Less than people think in one direction and considerably more in another.

Occupancy adds kitchen use above all. Two people at home make three meals a day in that flat instead of one, which means hob splatter, more washing-up sitting in the bowl, a bin that fills in four days rather than nine, and a fridge that gets opened forty times a day by hands that have been on a keyboard and a dog. It also adds bathroom use, floor traffic, and roughly double the tea-related activity around one square metre of worktop.

The dog adds hair, dander, saliva protein, and whatever comes in on four wet feet from Wandsworth Common. Hair is the visible part and the least important. It sits on top of things and lifts off cleanly with the right tool. Dander and saliva protein are the parts that build up in fabric and cause the smell that dog owners cannot detect in their own flat and every visitor notices within eight seconds of the door opening.

Hair, dander, and the stuff that comes in on the paws

Three different problems, three different remedies, and treating them as one job is why so many dog households feel like they are cleaning constantly and getting nowhere.

Hair is a floor and upholstery issue and responds to mechanical action. A vacuum with a motorised brush bar, or a rubber-bladed pet tool for fabric, will take it off in one pass. A cloth pushes it around.

Dander is skin, it is microscopic, and it goes into pile and weave and stays there. A vacuum takes a fraction of what is in a sofa cushion. The rest comes out with upholstery extraction, or with a washable cover that goes in at sixty degrees, and by Thursday of any given week the cushion has started refilling regardless.

Paw dirt is the one nobody prices correctly. A wet dog walking in off a London pavement carries grit, oil residue, dissolved road salt in winter and a fair amount of organic matter. That gets ground into the entrance-hall floor covering by every subsequent footstep. On a hard floor it is nothing. On the pale wool runner someone bought for the hallway of a flat on Sylvan Road in South Norwood, it is a maintenance liability that will outlive the dog.

So is a fortnight too long between visits?

Depends entirely on what you are measuring, and the honest answer has a timeline in it.

Days one to three after a clean, the flat holds. Days four to seven, the kitchen degrades first: hob, the strip of worktop by the kettle, the bin area, the fridge shelf where something has dripped. Days eight to eleven, floors reach the point where the dog hair is visible from a standing position in daylight, and the bathroom develops the beginnings of a tide line. Days twelve to fourteen, the soft furnishings and the smell start to register on anyone walking in from outside. Most customers ring on day eleven, which is to say by Thursday of the second week, and describe the flat as filthy when what they mean is that it has reached the state a normal flat reaches.

Only two of those four stages need a professional. The kitchen decay at day five is a five-minute wipe by whoever cooked. The floor at day nine is a vacuum. The bathroom and the fabrics and the accumulated build-up in the places nobody looks at need someone who is going to do it properly, and a fortnight is a reasonable interval for that.

What weekly buys that fortnightly does not

Weekly buys you a flat that never crosses into the day eight to eleven band, and it buys you the removal of a household argument about whose turn it is. Those are real benefits and I am not going to pretend otherwise.

What weekly does not buy is a deeper clean. The work per visit drops, the total hours go up, and you end up paying a skilled cleaner to do a job that has become light because it is being done too often. For most two-bed flats with a dog, weekly is convenience rather than necessity, and it is fine to buy convenience as long as you know that is what you are buying.

Which surfaces set the schedule?

Textiles. Not floors, which is where nearly every dog owner puts their effort.

The sofa is the single most important object in a dog household and the one that gets the least attention. It absorbs dander, oil from coat and skin, and moisture from a dog that lies on it damp. Fabric holds all of that in a way that a floor does not, and it releases it slowly back into the room every time somebody sits down. The smell people associate with dogs is mostly upholstery, curtains and bedding rather than the animal.

Machine-washable covers change the picture completely. Sixty degrees kills the bacterial component, the wash removes the protein, and the cushion goes back on smelling of nothing. A flat on Cann Hall Road in Leytonstone with two whippets and a pale linen-cover sofa smelled better than most dog-free households, because the covers went in the machine every three weeks without anyone making a fuss about it.

Fixed upholstery is harder. A leather or bonded sofa needs a wipe with an appropriate cleaner and then a conditioner every few months, because dog claws and body oils will dry it out along the seat front. A fixed fabric sofa needs upholstery extraction two or three times a year, which is a separate booking from a fortnightly clean and should be priced as one.

Then dog beds. Wash the cover weekly and the inner every month, and be honest about when the inner has gone. A foam base that has absorbed two years of a large dog is not going to come back, whatever anyone does to it, and a thirty-pound replacement does more for the flat than any amount of cleaning. Wash the cover on a Sunday and it is flat and warm again by Thursday, which is roughly the rate at which these things reset.

Curtains and blinds hold the same load at a slower rate. Fabric blinds in a kitchen where two people cook three meals a day pick up grease as well as dander, and once those two combine into a film they hold onto everything else.

The rug decision

Here is the opinion that annoys people: if you have a dog and a light-coloured rug in a hallway, get rid of the rug. Not clean it more often. Get rid of it.

Wool takes up soiling readily, hallway rugs get the wettest and dirtiest traffic in the flat, and no cleaning schedule that a normal person will sustain keeps one looking acceptable in a dog household. Customers spend more on rug cleaning over three years than the rug cost. A washable flatweave or a sealed hard floor with a proper coir mat at the door handles the same job and costs almost nothing to maintain.

Does being home all day help or hurt?

Both, and the balance falls differently in a flat than in a house.

It helps because problems get caught early. A spill gets wiped when it happens. It hurts because a two-bed flat with a small kitchen has nowhere for cooking moisture and cooking grease to go, and a household that produces three cooked meals a day in that space is loading the walls, the blind and the ceiling above the hob with a film that a fortnightly clean has to keep up with.

The extractor question

Most conversion flats have a recirculating hood with a carbon filter that nobody has changed since the kitchen went in. That filter has a working life of about six months in a household that cooks twice a day. Once it is spent, the hood is a fan that moves grease from one part of the room to another and nothing else.

A new filter costs about fifteen pounds and reduces the fortnightly kitchen workload more than an extra hour of labour would. A ground-floor flat on Hillview Gardens in Hendon had a hob wall that stopped needing degreasing between visits once the filter was changed and the window got opened while cooking.

When should you spend the money somewhere other than more cleaning?

When the fifteen minutes exists and nobody is doing it.

A dog household needs a short, dull, daily routine that has nothing to do with a cleaner: a vacuum of the main traffic route, a wipe of the hob and the worktop by the kettle, and a towel by the door for paws. Fifteen minutes, most days. That routine holds a flat between fortnightly visits comfortably, and no professional schedule substitutes for it, because the load is generated daily and a cleaner arrives twice a month.

Spend on a decent cordless vacuum kept in the hall rather than in a cupboard. Spend on washable covers. Spend on an occasional upholstery extraction. Only then, if the flat still feels wrong, consider weekly.

The other case for spending elsewhere is a flat that is working against you. A tenant in a maisonette on Windsor Avenue in Uxbridge was booking extra visits to deal with a hallway that greyed within days, and the cause was a doormat the size of a tea tray on a communal carpet that never got cleaned by anyone. A proper coir mat, six hundred millimetres deep, removed the problem for the price of two hours’ labour.

What a robot vacuum is worth in a dog flat

More than the trade likes to admit. Running one daily in a flat with hard floors keeps hair below the threshold where it becomes visible, which is the complaint that drives most requests to move from fortnightly to weekly. It handles the single job that generates the most anxiety and does it while nobody is in the room.

It will not do edges, it will not do stairs, and it will not touch anything that matters in a bathroom. Anyone selling one as a substitute for a cleaner is lying. As a substitute for the extra twenty-six visits a year that a dog owner thinks they need, it is the better purchase by a distance.

The couple in Fulham stayed fortnightly. The sofa covers now go in on a Sunday, and the labrador has a towel with his name on it.

Two cleaners, seven hours. That is what a proper one-off deep clean of a standard three-bed Victorian terrace costs you in labour, and the number moves either side of it by more than most people expect. A house on Sandringham Road in Hackney took us nine and a half. A near-identical footprint on Cranmer Avenue in Ealing came in at five and a quarter. Same era, same layout, same bay-fronted front room, same awkward half-landing with the window that opens onto next door’s flat roof. The difference was never square footage. It was what had been allowed to build up, and how much original fabric was still in place to work around.

What does a deep clean cover in a house this old?

A deep clean is the version of the job where nothing gets skipped because it is awkward. Tops of doorframes. Behind the cistern. The inside of the extractor hood rather than the front of it. Under the bed, which in a Victorian bedroom usually means shifting a divan that was assembled in the room and has never left it.

The term gets used loosely by every firm in London, mine included, so ask what is on the list before you agree a price. Some outfits sell a deep clean that is a regular clean with the skirtings wiped. Others treat it as everything short of carpet extraction and exterior glass. The gap between those two definitions is roughly eight hours of labour, which on paper looks like a pricing difference and in practice is a different service entirely.

Where the hours disappear in an 1890s build

Modern flats have flat surfaces. That is the whole story. A terrace built in the 1880s or 1890s has picture rails, cornicing, deep moulded skirtings, panelled doors with six recessed fields apiece, sash windows with beading, and a hallway of encaustic tile that has been mopped for a hundred and thirty years and stripped roughly never.

Panelled doors are the quiet killer. Count the cupboards and there are usually eleven or twelve internal doors in a three-bed terrace, and each takes six or seven minutes to do properly against the forty seconds a flush modern door takes. That is an hour of the day gone before anyone has looked at a kitchen. No customer has ever inspected a door and thought about where the time went.

Sashes are worse. A pair of boxed sashes in a bedroom on Pembroke Road in Walthamstow held about a decade of soot in the parting bead and the pulley stiles, and the only way to shift it was a brush, a vacuum crevice tool and patience. Forty minutes for two windows. There are usually seven or eight of them in the house.

So what is the honest hour count for a three-bed terrace?

Think in cleaner-hours rather than clock hours, because that is how the job gets priced and it stops the confusion about whether “six hours” means one person or three.

A house that is occupied, kept tidy and cleaned fortnightly by someone competent will run to somewhere between ten and thirteen cleaner-hours. That is two people for a long day, or three people for a shortish one. A house that has been lived in normally with no deep clean for two or three years lands between fourteen and eighteen. A post-tenancy property, a smoker’s house, a place with two dogs and a cat, or anything handed over at the end of a building job runs from twenty to twenty-eight and occasionally past that. A three-bedroom house is one job on paper and about four different ones by Tuesday afternoon.

Those bands hold across the whole of Greater London and they hold across most of the Victorian stock, whether the house is in Kensal Rise or Nunhead, because the houses were built to the same handful of pattern-book plans by the same speculative builders.

What a six-hour booking buys

Two cleaners for three hours each, which is what a lot of people picture when they ring up, buys the kitchen and one bathroom to a high standard. Or it buys the whole ground floor to a decent one. It does not buy both, and any firm that says it does is planning to skip something and hoping you will not check the inside of the fridge seal.

Here is the opinion that loses me work: fixed-price deep cleans are worse for the customer than hourly rates, and the industry pushes them because they hide the corner-cutting. A fixed price gives the contractor a fee and an incentive to finish early. An hourly rate gives you the right to stand in the hallway at hour five and say the landing skirtings need another pass. Most customers prefer the fixed quote because it feels safer. Most customers are wrong about that.

Which room eats the schedule?

The kitchen. It takes four to six hours of the total on its own, and in a Victorian house it takes longer than the same kitchen would in a 1990s semi, for reasons that have nothing to do with the units.

Ceiling height is the first one. A ground-floor rear kitchen in a terrace off Bramshill Road in Harlesden had 2.9 metres of wall, standard wall units at standard height, and a sixty-centimetre band of dust and airborne grease above them that had never been touched because nobody could see it from the floor. That band takes a steady forty minutes with a step platform and a degreaser that needs dwell time. It is invisible from every position a person occupies in that room, including the one they take when they inspect the work afterwards. Nobody has ever paid for that band of wall with any enthusiasm, on paper or otherwise.

Grease is the second. Cooking film does not sit on a surface, it bonds to it, and the older the film the longer the chemical needs to sit before it will shift. Cleaners who are behind schedule spray and wipe immediately, which removes the top layer and leaves a tacky base coat that will attract dust within a week. The customer sees a clean cupboard door on the day and a grey door in ten days and concludes that the cleaner was no good. The cleaner was rushed.

Then the specifics. Extractor filters need soaking, not scrubbing, and most terrace kitchens have a recirculating hood with a carbon element that should have been replaced two years ago. The gap between the cooker and the base unit holds a decade of debris in a strip forty millimetres wide. Kickboards come off, or they should. Fridge seals need a soft brush and a diluted solution worked into the folds, which takes twelve minutes per appliance and gets skipped almost universally. Splashback grout behind a hob absorbs grease and needs a proprietary cleaner and a stiff nylon brush, and it will not come back to white, only back to a uniform grey.

A galley kitchen in a Victorian rear extension has less floor area than a modern kitchen and more work in it. That is the part people find hard to accept when the quote arrives.

The oven is a separate job

Price it separately, book it separately, and treat it as its own trade. An on-site oven clean on a domestic double runs ninety minutes to three hours depending on carbon build-up, and it involves caustic products that should not be in the air while someone else is cleaning worktops two metres away.

Firms that fold the oven into a general deep clean either rush it or rob the rest of the house of the time. A dip-tank service, where the racks and panels go out to a van, will beat almost anything done in situ. If the oven matters to you, say so at the quoting stage rather than pointing at it on the day.

Does condition change the number more than size does?

Every time. A four-bed on Elms Crescent in Clapham came in under a three-bed in Bromley by two full cleaner-hours, because the Clapham house was minimalist to the point of austerity and the Bromley house had thirty years of family life in it.

Empty houses and occupied houses

An empty property cleans thirty to forty per cent faster. No decanting cupboards. No working around a sleeping shift-worker. No question of whether the paperwork on the desk should be moved, which is a question with no good answer, because moving it risks losing something and not moving it means the desk does not get cleaned.

In an occupied house we clean around possessions rather than through them, and that is a policy rather than laziness. The one exception worth making is the wardrobe floor, which is always worse than the customer thinks and always improves the smell of the room.

When is a deep clean the wrong thing to book?

Often enough that I turn work away most months.

If you are moving out in six weeks, wait. If builders are due, wait, because plaster dust travels through a closed door and will undo the lot in an afternoon. If the problem is one room, book that room and a half-day rather than a whole-house job you do not need.

The bigger one is when the problem is a repair rather than a clean. Perished grout, a failed silicone bead round a bath on Ravensbourne Road, black spotting on a north-facing bedroom wall that is condensation and will return in November whatever anyone sprays on it. Limescale in a pan that has gone past etching does not come back. We will tell you that on the phone and lose the booking, which is the correct outcome.

What to book instead

A fortnightly regular clean for three months will leave a house in better condition than a single deep clean and cost less in total for most three-bed terraces. The deep clean makes sense as a reset before a regular schedule starts, after a tenancy, or after building work. As a standalone annual event it is mostly ceremony.

The tiled hall floor on Sandringham Road came up in the end, after two passes and a neutraliser. Nobody had seen the pattern in years.

If your shower screen has turned from clear glass into a permanent fog of white spots and chalky film, London’s water is almost certainly to blame, and you are far from alone in fighting it. The capital sits on some of the hardest water in the country, and a glass shower screen is just about the most unforgiving surface that water can land on, showing every mineral deposit in sharp relief. The frustrating part is that the usual instinct – a quick wipe with whatever spray is under the sink – barely touches it, because limescale is not dirt and does not respond to ordinary cleaning. It is a mineral that has to be dissolved, not wiped. Get the chemistry right and a cloudy screen comes back to near-new clarity in an afternoon. Get it wrong, with the wrong product or an abrasive pad, and you can permanently damage the glass.

Why London Water Turns Your Shower Screen Cloudy

The chalk-aquifer reality behind hard-water limescale

To beat limescale it helps to know exactly what it is and why London suffers so badly from it. Much of the capital’s water is drawn from or filtered through the chalk and limestone that underlies the region, and as it moves through that rock it dissolves calcium and magnesium carbonates. The result is water that is rich in dissolved minerals – what we call hard water – and London consistently ranks among the hardest-water areas in the United Kingdom. Every time you shower, you are spraying mineral-laden water across the glass.

When that water dries, it evaporates and leaves the dissolved minerals behind as a solid deposit. That deposit is limescale: principally calcium carbonate, the same compound as the chalk the water came from. Each shower adds another microscopically thin layer, and because the screen rarely dries completely between uses, the layers build steadily into the cloudy, crusty film that resists every casual attempt to wipe it away.

The crucial point for removal is that limescale is alkaline, which is precisely why ordinary detergents fail against it – they are designed for grease and grime, not minerals. Limescale dissolves in acid, and that single fact underpins every effective method that follows. Understanding the enemy as a mineral deposit rather than as dirt is the shift that turns a hopeless scrubbing session into a quick, satisfying job.

First, Know What You’re Dealing With: Limescale vs Soap Scum

Telling mineral deposits apart from the greasy film

Before you treat the glass, it pays to identify what is actually on it, because shower screens usually carry two different problems that respond to opposite chemistry. Limescale is the hard, crusty, often spotty white deposit that feels slightly rough and is firmly attached. Soap scum is the greasier, smeary, duller film created when soap reacts with the minerals in hard water, and it tends to feel waxy rather than gritty. In a London bathroom the two almost always appear together, layered over one another, which is why a product that tackles only one leaves the screen looking little better.

The distinction matters because the two need different treatments. Limescale, being alkaline, is removed with acids such as vinegar or citric acid. Soap scum, being greasy and mildly acidic in character, often responds better to a degreasing or slightly alkaline cleaner. Throwing acid at a screen that is mostly soap scum, or detergent at one that is mostly limescale, explains a great deal of the frustration people feel when nothing seems to work.

The practical approach is usually to deal with the limescale first with an acid treatment, rinse thoroughly, and then follow with a degreasing wipe to lift any remaining soapy film. Doing it in that order means each problem meets the chemistry that actually defeats it, and the glass ends up genuinely clear rather than swapping one type of haze for another.

The Everyday Acid Method: Vinegar and Citric Acid

Why mild acids dissolve limescale and how to apply them safely

For everyday and moderate limescale, mild household acids are remarkably effective and cost very little. White vinegar, which contains acetic acid, is the classic choice. Citric acid, sold as a powder and dissolved in warm water, is just as good and has the advantage of a far less pungent smell – a real consideration in a small, enclosed bathroom. Both work by reacting with the calcium carbonate and converting it into soluble compounds that simply rinse away.

The key to success is contact time. A quick wipe achieves nothing because the acid needs minutes, not seconds, to dissolve the deposit. Warm the vinegar or citric acid solution slightly to speed the reaction, then keep it against the glass long enough to work. The most effective method is to soak paper towels or cloths in the solution and press them flat onto the vertical glass so they cling there, or to use a spray and reapply frequently so the surface never dries out. Leave it for fifteen to thirty minutes on stubborn areas.

After the dwell time, a non-scratch pad or a soft cloth lifts the softened scale easily, and a final rinse with clean water followed by a squeegee or microfibre buff leaves the glass clear. One safety rule overrides everything here: never mix any acid with bleach or bleach-based cleaners, as the combination releases toxic chlorine gas. Keep the bathroom ventilated and wear gloves, since even mild acids are unpleasant on broken skin.

Stubborn, Built-Up Scale: Stronger Tactics That Still Protect the Glass

Proprietary descalers, dwell time and what to avoid

When years of neglect have left a thick, crusty layer that mild acids only soften, it is time for stronger tactics – applied with more patience rather than more force. Proprietary limescale removers contain stronger acids, often formic or sulphamic acid, and are formulated to cling to vertical surfaces and cut through heavy deposits. Used according to their instructions, with the recommended dwell time fully observed, they will shift scale that household vinegar struggles with. A second or third application is far safer and usually more effective than reaching for anything abrasive.

The temptation with heavy build-up is to scrape or scour it off, and this is exactly the impulse to resist. Repeated treatment, letting the acid do the chemical work, is the route that protects the glass. For very thick spots, a plastic scraper or an old bank card held flat can lift softened scale after the acid has done its job, but metal blades and abrasive powders have no place near shower glass.

Coated or treated glass – many modern screens come with a factory applied water-repellent coating – needs particular care, because aggressive acids and abrasives can strip that coating and leave the glass performing worse than before. If your screen has such a coating, check what the manufacturer recommends and lean towards gentler, repeated treatments. When in doubt, test any strong product on a low, inconspicuous corner of the screen first and check the result before committing to the whole panel.

The One Mistake That Ruins Shower Glass for Good

Etched glass, abrasives, and why some cloudiness never comes off

There is one outcome worth understanding clearly, because it is permanent and entirely avoidable. Glass can be physically scratched by abrasive pads, scouring powders, wire wool and metal scrapers, and once it is scratched there is no cleaning it back to clarity – the marks are in the surface for good. This is why every method above leans on dissolving rather than scrubbing. A screen that looks hazy after cleaning is sometimes not still dirty but lightly scratched by a previous over-enthusiastic attempt.

There is also a subtler and more dispiriting form of permanent damage. When limescale is left on glass for years, particularly in a hard-water city, the minerals and the water can slowly etch and corrode the glass surface itself in a process sometimes called hard-water etching. The deposit effectively eats microscopic pits into the glass. When this has happened, the cloudiness is no longer a layer sitting on top that you can dissolve away; it is damage within the glass, and no amount of acid or effort will fully restore the clarity.

The lesson is twofold. Remove limescale before it has years to do this kind of harm, and never use anything abrasive in the meantime. If a screen remains permanently foggy after thorough, correct treatment, etching is the likely cause, and at that point replacement or professional polishing is the only real remedy rather than ever more aggressive cleaning.

Staying Ahead of It: Prevention in a Hard-water City

Squeegees, rinse aids, sealants and water softening

Removing limescale is satisfying, but in London the real victory is stopping it returning, and prevention is far easier than cure. The single most effective habit costs nothing: keep a squeegee in the shower and run it over the glass after every use. Limescale forms when mineral-rich water dries on the surface, so removing the water before it evaporates denies the scale the chance to form at all. A quick wipe with a microfibre cloth or towel does the same job.

Beyond that, several measures reduce the build-up between cleans. A water-repellent coating or sealant applied to clean, dry glass makes water bead and run off rather than cling, dramatically slowing deposition and making future cleaning easier – these need periodic reapplication but are well worth the effort in a hard-water area. A quick daily spray of a mild vinegar solution or a dedicated shower spray, left without rinsing, keeps light scale from establishing itself.

For a more fundamental fix, treating the water itself addresses the root cause. A water softener fitted to the supply removes the hardness minerals before they ever reach the shower, which not only protects the glass but extends the life of every appliance and fitting in a hard-water home. It is a larger investment, but in the chalk-fed reality of London water it is one that pays back across the whole property, not just the shower screen.

A dark splash of hair dye on a pale bathroom surface has a way of triggering immediate panic, and that panic is not entirely misplaced. Dye is engineered to bond permanently with whatever it touches, which is exactly what you want for your hair and exactly what you dread for your sink. The good news is that the surfaces in a bathroom are not made of keratin, and most of them can be brought back to their original state if you respond quickly and choose the right method for the material. The bad news is that the wrong approach – the wrong product, too much force, or simply waiting too long – can turn a recoverable splash into a permanent mark or, worse, damage the surface itself. This guide walks through what hair dye actually does to porcelain, ceramic, acrylic, tile and grout, and how to get each one clean without making the situation worse along the way.

Why Hair Dye Latches On So Fast (and Why Speed Matters)

The chemistry behind a stain that sets in minutes

Understanding why hair dye stains so aggressively is the key to beating it, because the same properties that make it so effective on hair are what make it cling to your bathroom. Permanent dyes work through oxidation: small colourless molecules penetrate a surface, then react with an oxidising agent such as hydrogen peroxide to develop into large coloured molecules that lock in place. On hair, this happens inside the shaft. On a bathroom surface, the same reaction is happening on and just below whatever the dye has landed on, which is why a stain that looks superficial can prove stubbornly anchored.

The decisive factor is time. While the dye is still wet and the colour-forming reaction is incomplete, much of it sits on the surface and lifts away with relatively little effort. Once it has fully oxidised and dried, the pigment has developed and bonded, and you are no longer cleaning a spill so much as trying to bleach out a finished colour. This is why the difference between wiping a splash immediately and discovering it an hour later is so dramatic. Porous and textured surfaces make everything worse, because the liquid wicks into tiny gaps and channels before it sets, giving the developed pigment far more to hold onto. Speed, then, is not just helpful but genuinely the most powerful tool you have, and it costs nothing.

First Response: What to Do the Moment Dye Hits a Surface

Blotting, rinsing and the mistakes that make it worse

The instinctive reaction to a dye splash is to grab a cloth and scrub, and that instinct, while understandable, can do real harm. Scrubbing a wet dye spill spreads the pigment outward, pushes it deeper into any texture, and can drive it into grout lines or scratches it would otherwise never have reached. The correct first move is to blot, not rub. Lay a clean, dry or damp cloth or paper towel onto the spill and lift the liquid away by pressing straight down, replacing the cloth as it picks up colour, until no more transfers.

Once you have lifted as much loose dye as possible, flush the area with plenty of cold water. Cold matters here, because warm water can accelerate the oxidising reaction you are trying to halt, effectively helping the stain develop. Keep the water moving across the surface rather than letting it pool, so the dye is carried away rather than spread around.

Work outwards from the edges of the spill towards the centre to avoid enlarging it, and resist the urge to reach for bleach or any strong product in this first minute. The immediate goal is simply removal and dilution. Only once the surface has been blotted and rinsed, and you can see what stain genuinely remains, should you move on to a targeted treatment chosen for the specific material you are dealing with.

Rescuing Sinks: Porcelain, Ceramic and Acrylic

Matching the method to what your basin is made of

Sinks are where dye splashes most often, and the right approach depends entirely on what the basin is made of. Glazed porcelain and ceramic, the materials in most traditional bathroom basins, have a hard, non-porous surface that resists staining reasonably well and tolerates fairly assertive treatment. For these, a paste of baking soda and water worked gently over the mark, or a cloth dampened with a little hydrogen peroxide left to sit for a few minutes, will usually lift a fresh stain. Stubborn marks on glazed ceramic can take a bathroom-safe bleach-based cleaner, applied briefly and rinsed thoroughly, since the glaze itself is not absorbent.

Acrylic and composite resin basins, common in newer and rented flats across London, demand more caution. These materials are softer, can be scratched by abrasive powders, and may be dulled or discoloured by harsh chemicals and undiluted bleach. Stick to non-abrasive methods here: a baking soda paste applied with a soft cloth, or a proprietary cream cleaner designed for acrylic, worked gently and rinsed away. Avoid scouring pads entirely, as the scratches they leave will trap dirt and dye far more readily in future.

Whatever the material, treat then rinse, and repeat the gentle treatment several times rather than escalating to something aggressive on the first attempt. A stain that fades a little with each pass is on its way out, and patience protects the surface in a way that brute force never will.

Tackling Wall and Floor Tiles

Glazed ceramic versus the special case of natural stone

Tiles divide neatly into two camps that must be treated very differently, and confusing the two is how genuine damage happens. Glazed ceramic and porcelain wall tiles, like glazed basins, have a sealed surface that gives dye little to grip. A splash on these usually responds to the same toolkit: a baking soda paste, hydrogen peroxide on a cloth, or a bathroom cleaner left to dwell for a few minutes before rinsing. Because the glaze is non-porous, the stain is almost always sitting on the surface rather than in it, which is encouraging news for removal.

Natural stone is the dangerous exception and deserves real care. Marble, travertine, limestone and slate are porous and, crucially, sensitive to acids. Many common stain removers, along with vinegar and some proprietary cleaners, are acidic enough to etch stone, leaving a dull, rough patch that is permanent and often more noticeable than the dye stain itself. On natural stone, avoid anything acidic and avoid bleach, and reach instead for a stone-safe poultice – a paste that draws the stain up and out of the pores as it dries. A pH-neutral stone cleaner is the safe everyday choice.

If you are unsure which type of tile you have, test any product on an inconspicuous corner first and wait to see the result. The few minutes this takes can save you from swapping a removable stain for an irreversible mark on an expensive surface.

The Grout Problem: Porous, Pale and Unforgiving

Why grout holds dye and how to draw it back out

Grout is the single most troublesome surface in this whole scenario, and it is worth understanding why before you attack it. Standard cement-based grout is highly porous, riddled with microscopic gaps that soak up liquid like a sponge, and it is very often pale or white, offering maximum contrast for a dark stain to show against. When dye reaches grout, it does not sit politely on the surface; it wicks down into the body of the material, which is why a grout stain can look as bad after surface cleaning as it did before.

Because the pigment is held below the surface, the trick is to draw it back out rather than wipe it off. A paste of baking soda and hydrogen peroxide, or a little oxygen bleach mixed into a thick paste, applied directly along the grout line and left to work for ten to fifteen minutes, gives the treatment time to penetrate and lift the colour. An old toothbrush lets you work it gently into the line without spreading dye onto surrounding tiles. Several patient applications usually outperform one aggressive scrub.

For grout that simply will not surrender, two further options remain. A grout pen or grout paint can cover a stain that has been cleaned as far as it will go, restoring an even colour. As a last resort, the top layer of grout can be raked out and refreshed. Sealing grout once it is clean and dry is the best protection against the next splash soaking straight back in.

Products That Work, Products That Wreck, and Knowing When to Stop

Building a safe escalation ladder and recognising a set stain

Pulling the methods together, the safest way to approach any dye stain is as a ladder you climb one rung at a time, starting gentle and escalating only as needed. The bottom rung is cold water and blotting, followed by a baking soda paste, then hydrogen peroxide, then oxygen bleach on a paste, and only at the top, on glazed and non-porous surfaces alone, a chlorine bleach product used briefly and rinsed well. Climbing slowly means you stop at the first thing that works and rarely reach for anything strong enough to risk the surface.

Some combinations should never be climbed towards at all. Never mix bleach with anything containing ammonia, and never combine different cleaning chemicals in the hope of a stronger result, as the fumes produced can be genuinely dangerous in an enclosed bathroom. Always ventilate, always wear gloves, and always rinse one product away fully before trying another.

There comes a point where a stain is simply set, particularly on porous grout or natural stone that has been left for days, and recognising that point saves both effort and the surface. A mark that has not shifted at all after several patient treatments is unlikely to yield to more of the same, and continued aggressive cleaning will damage the surface long before it removes the colour. At that stage, cosmetic solutions such as grout renewal, or professional restoration for stone and high-value finishes, become the sensible path – and in a rented London flat where a stained basin or floor could threaten a deposit, bringing in experienced help is often cheaper than the alternative.

A vacuum that suddenly gives off a hot, acrid smell mid-clean is unsettling, and the first question most people ask is whether the thing is about to catch fire or simply having a bad day. The honest answer is that it depends entirely on what kind of burnt smell it is and what your machine was doing when the odour appeared. A faint rubbery whiff after twenty minutes on a thick carpet is a very different problem from a sharp electrical stink that fills the room within seconds of switching on. Most burnt smells are mundane, fixable in ten minutes with no tools. A small minority are a genuine warning that something is overheating to the point of risk. Learning to tell those two apart is far more useful than either ignoring the smell or binning a perfectly good machine, so it is worth understanding what is actually happening inside the casing.

What That Burnt Smell Is Actually Telling You

Reading the difference between rubber, dust and electrical odours

Not all burning smells mean the same thing, and your nose is a more useful diagnostic tool than you might expect. Broadly, vacuum odours fall into three families, and identifying which one you are dealing with narrows the problem down immediately.

A hot rubber smell, slightly sweet and reminiscent of car tyres, almost always points to the drive belt – the rubber loop that spins the brush roll. A dusty, scorched smell, more like hot dust on a radiator, usually means the motor is running hot because something is restricting airflow. The one to take seriously is a sharp, chemical, electrical smell, the sort you might associate with an overloaded plug or melting plastic, which suggests the motor windings or wiring are overheating rather than just the air around them.

Timing tells you almost as much as the smell itself. An odour that builds gradually over a long cleaning session leans towards a benign cause such as a warm motor or a tired belt. A smell that appears within seconds of switching on, or comes with a change in the motor’s pitch, smoke, or the machine cutting out, belongs in the worrying category. Before you reach for any fix, switch off, unplug, and work out which family of smell you are dealing with.

The Usual Suspect: A Slipping or Burning Drive Belt

Why belts overheat and how to spot a failing one

In an upright or any vacuum with a powered brush roll, the drive belt is the single most common source of a burnt smell, and the good news is that it is also one of the cheapest and easiest things to put right. The belt is a thin rubber band that transfers spin from the motor to the brush roll. When the brush roll is hard to turn – because it is jammed with hair, wedged against debris, or its bearings are stiff – the motor keeps spinning while the belt struggles to move it. That friction heats the rubber, and hot rubber smells exactly like what it is.

You can usually diagnose this without tools. Turn the machine off, unplug it, and try to spin the brush roll by hand. If it will not turn freely, or the belt looks stretched, glazed, cracked or has flat spots worn into it, the belt is your answer. A belt that has snapped entirely often leaves a stronger burnt smell at the moment it goes, along with a brush roll that no longer spins at all even though the motor sounds normal.

Belts are wear items, much like brake pads on a car, and most are designed to be replaced periodically. Across the dusty, high-traffic flats and houses of London, where carpets see plenty of grit tracked in from the street, belts tend to wear faster than the manuals suggest. Replacing one is usually a matter of removing a base plate, slipping off the old belt and looping on a new one, and it costs very little.

Blockages and Overheating: When Airflow Gets Choked

How a clogged hose, full bin or dirty filter cooks the motor

Vacuum motors rely on a constant stream of air not only to lift dirt but to cool themselves. Choke that airflow and the motor has no way to shed its heat, so it runs hotter and hotter until it either trips its safety cut-out or starts to smell of scorched dust. This is probably the second most common cause of a burnt odour, and it accounts for a great many machines that get written off when nothing is actually broken.

The culprits form a predictable list. A bag or bin filled past the line restricts airflow long before it looks completely full. Filters – foam, felt or HEPA – clog with fine dust over months of use and are very often the forgotten component, especially in homes that have never had them cleaned or swapped. Hoses and wands trap blockages, and in older conversion flats a sock, a hair clip or a wad of compacted fluff can lodge out of sight and slowly strangle the suction.

The fix is methodical rather than technical. Empty the bin or change the bag, remove and wash or replace the filters according to the manual, and check the full airflow path from floorhead to motor for obstructions. A coin dropped down a detached hose should rattle straight through; if it stops, you have found your blockage. Many machines also have a thermal cut-out, so if yours keeps stopping and restarting after it cools, treat that as a strong hint that something is overheating and choking for air.

The Brush Roll Problem (Especially in Pet and Long-Hair Households)

Tangled bristles, seized bearings and the friction smell

The brush roll deserves its own attention because it sits at the root of so many belt and overheating problems, and because some homes punish it far harder than others. Long human hair, pet fur and carpet fibres wrap themselves around the roller with remarkable persistence, building into tight bands that wind around the ends near the bearings. Once that happens, the roller drags, the belt fights to turn it, and you are back to the hot rubber smell described earlier.

Households with dogs, cats or long-haired occupants – a fair share of London flats – see this constantly, and the build-up can be surprisingly invisible until you look closely. Switch off and unplug, then run your fingers along the brush roll. If you find hair wound tightly at either end, a pair of scissors or a seam ripper makes short work of cutting it free, after which the roller should spin smoothly again.

A second, less common issue is the bearings the brush roll spins on. Over years of use these can dry out or seize, so even a clean roller turns stiffly and generates friction heat. If the roller is clean but still will not spin freely by hand, worn bearings or a bent roller may be to blame, and on many machines the whole brush roll assembly can be replaced as a single inexpensive part.

When the Motor Itself Is the Problem

Recognising electrical burning and a genuinely failing motor

If you have ruled out the belt, cleared every blockage, washed the filters and freed the brush roll, and the smell persists, the motor itself moves up the list of suspects. This is the more serious end of the diagnosis, though it is also the least common, and it is worth approaching calmly rather than assuming the worst.

A motor that is genuinely failing tends to announce itself in ways the earlier causes do not. The smell is sharper and more chemical, closer to burning plastic or hot electrics than warm rubber or dust. You may notice the motor labouring, changing pitch, sounding rougher than usual, or sparking visibly through the vents – many vacuum motors have carbon brushes that spark a little in normal use, but heavy or constant sparking is not normal. In the worst cases there is visible smoke or a smell that lingers in the room long after the machine is switched off.

A motor reaching the end of its life, with worn carbon brushes or degrading winding insulation, will overheat regardless of how clean and clear the rest of the machine is. At this point the honest assessment is whether the vacuum is worth repairing at all. Motor replacement is a significant job and often costs a large fraction of a new machine, so on cheaper models it rarely makes financial sense. An electrical burning smell from the motor is not something to keep using through.

When to Actually Start Worrying (and What to Do About It)

Telling a quick fix from a fire risk or a write-off

Pulling all of this together, the line between a minor annoyance and a real worry is clearer than the alarm of the moment suggests. A warm or rubbery smell that fades once you clean the filters, clear a blockage, free the brush roll or fit a fresh belt is firmly in the routine-maintenance category. These machines are not dangerous; they were simply asking for the upkeep every vacuum needs, and they will go back to running normally once you have dealt with the cause.

The signs that warrant genuine concern are worth committing to memory. Smoke, visible sparking beyond the faint flicker of healthy brushes, a sharp electrical or melting-plastic smell, a casing that is too hot to hold comfortably, or a machine that repeatedly cuts out and will not stay running all mean the same thing: stop, switch off, and unplug at once. A vacuum is a high-powered electrical appliance full of fine, flammable dust, and an overheating motor near that dust is the one scenario that carries a real fire risk, however rare it is in practice.

When you reach that point, the sensible response is to stop using the machine entirely rather than persevering in the hope it settles down. Depending on the age and value of the vacuum, that means either a proper repair by someone competent with electrical appliances or accepting that the machine has come to the end of its working life. Either way, a burnt smell is information, and reading it correctly lets you fix the small things quickly and respect the few that genuinely deserve your caution.