TL;DR
Polished concrete gets its shine from mechanical grinding plus a chemical densifier that hardens the surface, not from a coating you can strip and reapply. Acid attacks that densified layer and etches it permanently. Clean with a pH neutral cleaner, control grit obsessively, and never let a spill sit -- the surface is far more porous than it looks.
What polished concrete actually is
A polished concrete floor is ground with progressively finer diamond abrasives, then treated with a chemical densifier -- usually a silicate that reacts with the concrete and hardens the top few millimeters. Some floors get a topical guard or sealer on top of that.
The shine is a property of the ground and hardened surface itself. There is no film sitting on top the way there is on a wood floor. That means you cannot restore gloss by adding a product, and it means damage to the surface is damage to the floor.
Source: concrete polishing industry association technical guidance.
Why is acid such a problem on concrete?
Concrete is alkaline, made of calcium compounds, and acid dissolves calcium. Vinegar, lemon juice, wine, citrus cleaners, and acidic bathroom products all etch a polished surface, leaving dull spots that no amount of cleaning brings back.
Etching is physical damage, not a stain. The surface has literally been dissolved away in that spot. The fix is regrinding and repolishing, which is contractor work, not a Saturday project.
This makes polished concrete behave a lot like natural stone, and the same rule applies: neutral cleaners only. The reasoning is laid out in why a pH neutral cleaner matters here.
Grit is the other enemy
Ground and densified concrete is hard, but it is not scratch-proof. Sand tracked in on shoes acts like loose abrasive underfoot, and over months it takes the gloss down in traffic lanes while the edges of the room stay bright.
Dry dust mop or vacuum daily in busy areas, using wide microfiber rather than a broom, which flicks grit instead of capturing it. Walk-off mats at every exterior door do more for the floor's appearance than any product you can buy.
The routine
Start dry, every time. Then damp mop with a pH neutral cleaner diluted per its label, on a well-wrung microfiber pad.
Concrete tolerates more water than wood does, so you have more latitude here, but there is still no reason to flood it. Standing water in an unsealed or poorly sealed area soaks in and can leave a dark patch that takes days to fade. Follow with a dry pass in hard water areas so minerals do not dry on the surface as a haze. The mechanics are the same as any hard floor and are covered in the damp mop technique.
What to avoid
| Never use | Why |
|---|---|
| Vinegar, lemon, citrus cleaners | Acid etches the densified surface permanently |
| Bathroom and descaling products | Almost always acidic |
| Ammonia and strong alkaline degreasers | Degrade a topical guard and can discolor |
| Abrasive powders and scouring pads | Scratch the polish |
| Wax and floor polish | Builds a film that yellows and hides the real surface |
| Bleach | Can discolor integrally colored or dyed concrete |
| Muriatic acid | Aggressively etches; a concrete stripper, not a cleaner |
Never mix chlorine bleach with any acid or with ammonia. Both pairings release toxic gas, and floor cleaning is a common place people combine products without thinking. Keep one product in the bucket at a time.
Spills need to be handled immediately
Even a well-densified floor is more porous than it looks. Oil, wine, coffee, pet accidents, and cooking grease can penetrate and leave a shadow that is genuinely difficult to remove later.
Blot -- do not wipe, which spreads it -- then clean the area with neutral cleaner and rinse. For an oil spot that already soaked in, cover it with an absorbent powder, let it draw the oil out over several hours, then sweep and clean.
How the shine comes back
If the floor has gone dull in traffic lanes but is not etched, burnishing usually restores it. A low-speed machine with a soft pad warms and re-levels the surface, bringing the gloss back without adding anything to it.
If the dullness is patchy, ring-shaped, or matches where a spill happened, that is etching and burnishing will not fix it. Regrinding at a fine grit is the remedy, and that is specialist work.
Before assuming either, rule out residue. Mop a test section with plain warm water only and dry it. If that patch looks better, you have film buildup from over-concentrated cleaner, which is by far the most common cause of a dull-looking floor -- see why floors go dull after mopping.
Sealed, densified, or coated?
Ask what your floor actually has, because it changes what is safe. A densified-only floor relies entirely on the hardened surface. A floor with a penetrating sealer has some stain resistance but the same acid sensitivity. A floor with a topical urethane or epoxy coating is really a coated floor and takes coating-appropriate care.
If you do not know, the water bead test gives a hint: water that beads tightly suggests a topical coating, while water that darkens the surface slightly and then dries back suggests densified or penetrating-sealed concrete. A basement or garage slab is usually neither, and that surface is handled differently -- see cleaning an unpolished garage floor.
Terrazzo, which is marble chips in a cement or epoxy matrix, has an overlapping but not identical rule set, and terrazzo, which behaves similarly is worth reading if you have both in one building.
FAQ
Can I use vinegar on polished concrete floors?
No. Vinegar is acidic and concrete is alkaline, so the acid dissolves the densified surface and leaves permanent dull etch marks. The damage cannot be cleaned off -- it requires regrinding. Use a pH neutral floor cleaner instead.
What cleaner is safe for polished concrete?
A pH neutral floor cleaner diluted exactly as its label states. Neutral cleaners lift soil without attacking the densifier or degrading a topical guard, and they rinse clean instead of leaving a film that dulls the reflection.
Can you steam mop polished concrete?
Concrete tolerates heat better than wood or vinyl, but steam offers no real advantage and can degrade a topical sealer or guard over time. A damp microfiber mop with neutral cleaner cleans just as well with no risk to the coating.
Why does my polished concrete have dull spots?
Dull spots that match where something spilled are almost always acid etching, from wine, citrus, a cleaning product, or pet urine. Dull areas along walking paths are usually grit wear. Etching needs regrinding; wear often responds to burnishing.
How do I get an oil stain out of concrete?
Cover the spot with an absorbent powder to draw the oil up over several hours, then sweep it away and clean with a neutral cleaner. Repeat as needed. Deep stains on porous concrete may lighten substantially without disappearing entirely.
Does polished concrete need to be sealed or waxed?
It should never be waxed -- wax builds a film that yellows and defeats the point of a polished surface. Whether it needs a penetrating sealer or guard depends on the original specification and the traffic. Ask whoever installed or last serviced the floor.
When the whole house is the problem rather than one task, recurring house cleaning services are the wider option.
Concrete looks indestructible and is not, which is exactly why it ends up etched in kitchens and entryways. Every home is different, so what a full clean takes depends on size, condition, and what you want covered. Get a quote and we will walk you through it.