Materials & surfaces
What a thing is made of decides what is safe to clean it with. Most useful cleaning rules are properties of the material, not of the object.
Listed alphabetically.
Acrylic
A polymer, so the things that damage it are solvents and aggressive chemistry rather than acid or alkali. Almost the opposite of the china beside it.
Carries warnings
Alabaster
Looks like polished marble, is chemically nothing like it, and dissolves in water. The one surface where blotting a fresh spill is the error.
Carries warnings
Aluminium
Protected by its own oxide layer, but amphoteric: attacked by strong alkalis as well as strong acids, which rules out many oven and dishwasher products.
Carries warnings
Aniline leather
Dyed the way wood is stained rather than painted. There is no film on top, so anything spilled goes in — and the cleaner darkens it on contact.
Carries warnings
Anodised aluminium
An oxide layer grown into the metal rather than laid on it. A standards body names five specific chemicals that must never touch it, and the damage is permanent.
Carries warnings
Appliance seal rubber
The soft closure between a door and a cavity. Its job is a shape, and most cleaning advice that reaches it is about to change that shape.
Architectural bronze
Outdoor copper alloy where the green is not dirt, cleaning will not restore it, and the wax afterwards is what the cleaning was for.
Carpet
A textile floor covering where the instinctive response to a spill — scrubbing — is the one the trade body specifically rules out.
Carries warnings
Casein plastic
A plastic made from milk protein. It is one of the very few materials that pests eat because it is food.
Carries warnings
Cellulose acetate
The safer replacement for celluloid, and still a material that warps, crazes and blooms rather than simply getting dirty.
Carries warnings
Cellulose nitrate
One of the first man-made plastics and one of the least stable. An acidic smell is the warning that arrives before anything looks wrong.
Carries warnings
Cement and mortar
Alkaline, porous and carbonate-bearing — which means acid dissolves it, and it damages an aluminium finish if allowed to dry on one.
Carries warnings
Ceramic glass
The heat-resistant glass used in stove doors and ceramic hobs. Chemically robust and thermally tough, but readily scratched, and scratches are permanent.
Carries warnings
Chrome plating
A thin decorative chromium layer over another metal. Hard and bright, but once the plating is breached the metal underneath corrodes and no cleaning reverses it.
Carries warnings
Coated aluminium
Aluminium with an anodic or organic finish on it. The finish is the thing at risk, not the metal — and marks from mistreating it may be permanent.
Carries warnings
Coated spectacle lens
A coated optical surface where the hazard is not the cleaner but the grit in whatever you wipe it with — and where a scratch is replaced rather than repaired.
Carries warnings
Coated upholstery
Smooth, non-permeable and still a SOFT surface — which is why the hard-surface spray that seems obviously right for it is the thing most likely to wreck it.
Carries warnings
Concrete and stone paving
A hard outdoor surface whose weak point is not the slab but the JOINTS between slabs — which is why the standard advice to blast it with a pressure washer is fenced by an angle.
Copper and brass
Tarnish is the metal reacting with its surroundings, not dirt on top of it. Every polish that removes it removes metal too.
Carries warnings
Cotton
A cellulose fibre, tolerant of hot water and alkaline detergents — and measurably degraded by chlorine bleach, which cuts the cellulose chains themselves.
Carries warnings
Engineered quartz
Ground quartz bound in resin. Non-porous and acid-tolerant where marble is not — but the resin is the weak point, and the products sold for real stone are wrong for it.
Carries warnings
Expanded polystyrene (helmet foam)
The material inside a cycle helmet, and a rare case where a cleaning mistake destroys the function of the object and leaves NOTHING TO SEE.
Fingerprint-resistant stainless steel
A coated finish over stainless, and the coating is what you are cleaning. Several things that are fine on bare stainless are prohibited on this, with the warranty attached.
Carries warnings
Finished leather
Modern leather carries a water-based finish, which is why the traditional leather products — saddle soap, mink oil, wax — are on the prohibited list rather than the recommended one.
Carries warnings
Finished wood flooring
The finish is the surface, not the wood — and the two things that ruin it are water and the cleaners people reach for to remove water marks.
Carries warnings
Galvanised steel
Steel protected by a sacrificial zinc layer. Alkaline cleaners dissolve that layer and give off hydrogen doing it, leaving the steel exposed.
Carries warnings
Glass
Chemically tough and mechanically fragile. Almost all damage to glass is grit dragged across it, not the cleaner used on it.
Carries warnings
Gold
Almost nothing attacks it, which is why the damage that does happen is nearly always done by the person cleaning it.
Gold plate and vermeil
A finite thickness of gold over something else. Every polish spends some of it, and there is no way to put it back.
Carries warnings
Granite
A silicate stone that resists kitchen acids where marble does not — and on which acidic cleaners are still not recommended, for reasons that are not about the stone.
Grout
Cement-based grout is porous and alkaline, and acids dissolve it. That single fact rules out most of what bathroom cleaning advice recommends for it.
Carries warnings
Household plastics
The catch-all for the polymer surfaces in every room. Solvents do not clean them, they dissolve them — and the same word covers a dozen different polymers.
Carries warnings
Ivory
The yellowing everyone wants removed is the material ageing, and the conservation authority's instruction is to leave it. Almost every circulating method attacks a patina rather than a stain.
Jute
A plant fibre used for rug backings and natural-fibre floor coverings, and the classic case of a material that browns rather than stains.
Lacquered metal
Brass, copper or steel under a clear film applied to stop it tarnishing. Every metal polish sold for the metal underneath attacks the film instead.
Laminate flooring
A wood-based board under a resin surface. The board is why water is the enemy, and why the trade body rules out steam without qualification.
Carries warnings
Laminate worktop
A printed decorative layer over a chipboard core. The surface is tough and the edge is not, and almost every failure starts at a joint.
Carries warnings
Limestone
Calcium carbonate like marble, but softer and more porous. Everything that damages marble damages it faster, and it absorbs more.
Carries warnings
Memory foam
An open-cell foam that holds any liquid it takes in and dries from the inside outwards. The manufacturer's instruction is not a cleaning method — it is that it should never get wet.
Carries warnings
Microfibre
A split synthetic fibre whose cleaning power is structural rather than chemical — which is why filling that structure with anything, including fabric conditioner, destroys it.
Carries warnings
Mirrored glass
Glass with a reflective backing and exposed edges. The trade body's guidance rules out both vinegar and ammonia — which is nearly everything sold for cleaning it.
Carries warnings
Natural rubber
The material appliance seals, mats and gloves are made of, and it is attacked from both ends of the chemistry — by solvents and by caustics alike.
Carries warnings
Non-stick coating
A behaviour, not a material — and the sources that give cleaning rules for it usually decline to say which coating it is, so the rules are mechanical.
Carries warnings
Nubuck
Aniline leather sanded to a short nap — and the trade's cleaning method is to sand it again, because the soil is in the fibres rather than on them.
Oiled wood
A finish inside the timber rather than on top of it. That makes it repairable in patches and vulnerable to anything that strips oil.
Carries warnings
Olefin
The one common textile fibre that chlorine bleach does not decolour. That single property changes where it belongs and what may be used on it.
Painted walls
A soft coating that is still curing for weeks after it looks dry, and that is damaged by water as readily as by any cleaner.
Phenolic plastic
The first fully synthetic plastic, and durable enough that its real cleaning risk is what somebody does to it rather than what it does to itself.
Carries warnings
Plated and coated tap finishes
Modern taps are a coating on a metal, microns thick. The finish decides the rules, and the rules genuinely differ between finishes on the same basin.
Carries warnings
Polished marble
A calcium carbonate stone with a polished finish. Chemically attacked by acids, including household ones, and the damage is permanent.
Carries warnings
Polyester
A synthetic fibre that resists the chemistry which degrades cotton and wool, and is instead limited by heat — and it holds oily soil more stubbornly than either.
Polyurethane foam
Crumbles from the inside as it oxidises. Nothing in a cleaning cupboard slows it and oxygen is the cause.
Carries warnings
Porcelain tile
The trade defines porcelain by a number: water absorption of 0.5% or less. That number is why one tile stains and another does not.
Powder-coated aluminium
A baked organic coating over metal. Strong solvents and abrasives attack the coating, and the rule of thumb for what is mild enough is unusually memorable.
Sandstone
A siliceous stone that mostly shrugs off acid — except where its own iron content reacts, and then acid washing turns the paving orange.
Carries warnings
Seasoned cast iron
Bare iron protected by a baked-on oil layer. Water is the enemy, not detergent — and the manufacturer says so more plainly than the folklore does.
Carries warnings
Seat belt webbing
A load-bearing textile with a surface finish on it — which is why the softest cloth in the cupboard is the wrong one.
Carries warnings
Silicone sealant
The flexible bead round a bath or a worktop, and the most common place a household meets mould it cannot remove — because the growth is inside the material.
Silver plate
A microns-thin layer of silver over a base metal. Everything that cleans sterling also thins the plating, and once it is through there is nothing underneath to polish.
Carries warnings
Slate
The stone that survives what the others do not. A paving manufacturer names it among the materials acid washing leaves unaffected.
Solution-dyed acrylic
Outdoor fabric with the colour built into the fibre rather than applied to it — which is why its maker specifies bleach where it is prohibited almost everywhere else.
Carries warnings
Stainless steel
Steel protected by a self-repairing chromium oxide layer. Resistant to most household cleaning, and specifically vulnerable to chlorides and to abrasion across the grain.
Carries warnings
Sterling silver
92.5% silver, and a rare material where the standard domestic treatment permanently removes some of the object. Tarnish contains silver, so cleaning it off costs silver.
Carries warnings
Suede
Not finished leather with a texture — a different cut of the hide, porous and undyed at the surface, where even clean water leaves a ring if it is hard.
Carries warnings
Travertine
A calcium carbonate stone with open pores running through it, so it is acid-sensitive and absorbent at the same time — the worst pair of properties in a bathroom.
Unglazed ceramic tile
Defined by a number rather than a look: more than half a per cent water absorption. That figure is how a stain gets in, and it is why sealing matters here and not on porcelain.
Upholstery fabric
Carpet advice does not transfer to it. The manufacturer's rules start with what NOT to vacuum with, and water is on the prohibited list rather than the method list.
Carries warnings
uPVC
The commonest window frame in the UK and the material with the most confident wrong advice attached to it. The manufacturer permits a cream cleaner — sparingly, and not on woodgrain.
Carries warnings
Vehicle clear coat
A transparent film a fraction of a millimetre thick doing all the work. Everything that looks like a stain on car paint is usually an etch in this layer.
Vinyl flooring
A polymer floor whose wear surface is often a finish rather than the vinyl itself — which is what solvents and all-purpose cleaners attack.
Carries warnings
Viscose and rayon
A cellulose fibre that the professional body describes as very sensitive to water — and the shape can be lost to a dissolving finish rather than to the fibre.
Carries warnings
Vitreous china
The one bathroom surface where the manufacturer permits a soft abrasive. The fittings around it are what you have to protect.
Vitreous enamel
Glass fused onto metal. Hard, but a scratch goes through to the iron and does not come back.
Carries warnings
Waterproof outerwear
The one garment family where the manufacturer prescribes the tumble dryer rather than warning about it — because heat is what restores the water repellency.
Carries warnings
Waxed wood
The traditional finish, and the one most damaged by modern cleaning habits: water marks it, heat softens it, and detergent removes it.
Wool
A protein fibre. The wool industry body advises against bleach of any kind and against enzyme detergents, and heat with agitation felts it irreversibly.
Carries warnings
Almost every genuinely useful safety rule is a property of the MATERIAL rather than of the object: nobody writes a rule about a marble windowsill, they write one about calcium carbonate, and the windowsill inherits it. Which is why the least intuitive place to look is usually the right one.