Polished Concrete Grit Sequence: Grind & Seal to High-Gloss
Metal bonds cut, resin bonds refine. How deep you cut and how far up the ladder you go are two separate decisions, and only one of them is about shine.
Metal-bond diamonds cut the slab and decide how much stone shows. Resin-bond pads refine what the metal left and decide how much it shines. Every pass exists to remove the scratch pattern of the one before it, so the ladder is climbed in order, and where you stop is the finish level you sold.
Two decisions, not one
Most disagreements about a polished floor come from treating the finish as a single choice. It is two, and they are independent. Exposure is how deep the metal passes cut, which sets how much aggregate is revealed. Sheen is how far up the resin ladder you then go, which sets how reflective the surface is. A cream floor can be taken to a mirror gloss; a full-exposure floor can be left matte and honed.
They also cost differently, and this is the part worth carrying into a quote. Metal passes run at the slow end of the rate scale, so exposure is expensive. Resin passes are roughly twice as fast, so sheen is comparatively cheap. On a 1,000 ft² floor at the rates the calculator seeds, moving from a cream cut to full exposure adds around 12 hours. The entire four-step resin ladder of a Polished finish adds under 9. Depth costs more than shine.
Metal cuts, resin refines
Metal-bond tooling is for removal: taking off coatings and adhesive, flattening high spots, and opening the surface to the depth you want. It is aggressive and slow, and the coarse metal passes dominate the hours on any polished job. Resin-bond pads barely remove material at all. Their job is to progressively erase the scratch pattern the previous grit left, until the surface is uniform enough to reflect light.
That is why skipping rungs does not work. Jump from 100 straight to 400 and the 400 pad is being asked to remove scratches it was never built to reach. You either leave them in the floor, where the client will find them under a low winter sun, or you spend longer at 400 than the missed pass would have cost.
How deep the metal goes: the four exposures
Cream
- One light surface cut at 150 grit
- Minimal aggregate: you are polishing the surface paste
- Cheapest to cut, but unforgiving of a slab that is not flat
Salt & Pepper
- Two metal passes, 80 then 150
- A shallow cut that reveals the fine sand, not the stone
- The most common commercial look
Medium
- Three metal passes, 40 then 80 then 150
- Partial stone showing. The default the calculator seeds
Full exposure
- Four metal passes, including a repeated deep 40 grit cut
- Large aggregate revealed across the floor
- Slab-dependent: the stone has to actually be there, at that depth
How far up the ladder: the four finish levels
Hours below are for a 1,000 ft² floor at medium exposure with one machine, at the rates the calculator seeds. They are there to show the shape of the increase, not to be quoted:
Grind & Seal
- Metal passes, densifier, guard. No resin polishing at all
- Matte to low sheen
- About 13.5 hours
Honed / Satin
- Resin ladder to 400 grit
- Smooth, low reflection, easy to keep looking even
- About 20.2 hours
Polished
- Resin ladder to 800 grit
- Semi-gloss, visibly reflective
- About 22.4 hours
High-Gloss
- Full ladder to 1500 and 3000 grit, then guard, then a burnish
- Mirror finish, and the most sensitive to a poor cut underneath
- About 28.5 hours
The gap between Honed and Polished is one resin pass, a little over two hours on this floor. The gap between Grind & Seal and anything polished is much larger, because that is where the resin ladder starts.
Where the densifier and the guard sit
The densifier goes in after the metal grinding and before the resin polishing. It hardens the surface by reacting with free lime in the concrete, and it needs a surface that is open enough to absorb it: ground, but not yet closed up by the fine resin passes. Applied too early it is ground back off, and applied too late it sits on top of a surface that cannot take it in. Neither mistake announces itself on handover day, which is why it is worth getting right. It shows up months later as a floor that dusts and dulls early.
The guard goes on near the end, and on a high-gloss floor a burnish follows it. Burnishing is a high-speed buff rather than a cut, so it runs faster than any polishing pass and should carry its own production rate. It is also the pass you will come back for: a dulled traffic lane can often be brought back with a burnish and fresh guard instead of a full re-polish, which is a maintenance conversation worth having at handover.
Cost a sequence
Load a finish, set the exposure with the metal passes, and edit every grit rate to match your machines and the slab.
Add or remove grits, switch a pass to cross-hatch, and read the hours per pass.
Open the live calculator →Common mistakes
- Agreeing a sheen with the client and never agreeing an exposure, then absorbing extra metal passes when they expected more stone
- Skipping grits to save time, which either leaves visible scratches or costs more at the next pad
- Promising full exposure without knowing what aggregate is in the slab or how deep it sits
- Running the densifier before the metal passes are finished
- Giving burnish the same production rate as a resin polish, which overstates the hours on a high-gloss job
Once the sequence is settled, turning it into hours, days and money is mechanical: how to price polished concrete by grit pass. If you are still deciding whether this floor should be polished at all, start with polished concrete vs epoxy.
Frequently Asked Questions
What is the difference between metal-bond and resin-bond tooling?
Metal-bond diamonds are for removal. They cut into the slab, take off coatings, adhesive and high spots, and open the surface up to whatever depth of aggregate you are after. They are aggressive and comparatively slow, which is why the coarse metal passes dominate the hours on any polished job. Resin-bond pads are for refinement. They do not remove much material at all; they progressively take out the scratch pattern left by the previous grit until the surface reflects. That is the whole logic of the sequence: metal decides what the floor looks like, resin decides how much it shines.
Do I have to run every grit, or can I jump steps?
Each pass exists to remove the scratches left by the one before it. Jump from 100 to 400 grit and the 400 pad is being asked to erase a scratch pattern it was never designed to reach, so you either leave those scratches in the floor permanently (visible under any raking light, which is exactly where clients look) or you spend longer at 400 than the two passes would have taken. Skipping steps is the classic way to lose money and quality at the same time. The place where genuine time is saved is choosing the right exposure and the right finish level at the quoting stage, not dropping rungs off the ladder on site.
What is aggregate exposure, and is it the same as the sheen level?
They are two independent decisions, and confusing them is the most common misunderstanding on a polished job. Exposure is how deep the metal passes cut: cream (barely into the surface paste), salt and pepper (a shallow cut showing the fine sand), medium, or full exposure (a deep cut that brings out the large stone). Sheen is how far up the resin ladder you go afterwards. You can have a cream floor polished to a high gloss, or a full-exposure floor left honed and matte. They are priced differently too: exposure adds metal passes at the slow end of the rate scale, while sheen adds resin passes at the fast end. Agree both with the client in writing, and put both on the quote.
Where does the densifier go in the sequence, and why there?
After the metal grinding and before the resin polishing. The densifier reacts with free lime in the concrete to harden the surface, and it needs the ground surface open enough to penetrate, which it is once the metal passes have cut it and before the resin passes have started closing it up. Applied too early it is ground straight back off; applied too late it sits on a surface that is already tight and cannot take it in. Putting it in the wrong place does not usually produce an obvious failure on handover day, which is precisely why it is worth getting right: the consequence shows up as a floor that dusts and loses its sheen early.
Is burnishing a separate pass, and does it need its own rate?
Yes to both. Burnishing is a final high-speed buff, usually over the guard, and it is what produces the last increment of gloss on a mirror finish. It runs faster than a polishing pass because it is not cutting anything, so it should carry its own production rate rather than inheriting a resin rate. It is also the pass most often used later in a floor’s life: a polished floor that has dulled in the traffic lanes can frequently be brought back with a re-burnish and fresh guard rather than a full re-polish, which is a maintenance contract worth quoting for at handover.