Low spots and boot prints in polished concrete: 5 choices
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Low spots and boot prints in polished concrete come from the day of the pour. Someone walked on the slab while it was soft, or the crew left it wavy. A polish machine has a big flat head that rides on the high spots and floats over the dips. The high spots shine, and the low spots stay dull next to them.
Your Slab Boss Polish quote gives you 5 choices for this. The first one costs nothing. The other 4 are billed at $67 per hour, counted by the crew hour as worked, because no one can say how deep a dip goes until the crew is grinding it.
Why low spots stay dull
A polish machine has a big flat head. It rides on the high spots and floats over the dips, so the dips stay dull. Low spots come from a wavy pour or from boot prints made while the slab was soft.
Leave low spots as they are
Free and fast.
Pro: Nothing is added to your price.
Con: Low spots stay dull and show from across the room.
Hand-polish the low spots
We polish each low spot by hand with flexible pads.
Pro: The spot gets shine and is easier to clean.
Con: The dip stays.
Cut out, fill, and polish as a patch
We cut the spot out, fill it, and polish it flat.
Pro: The spot is flat.
Con: It looks like a patch. Plus materials.
Grind the area down to the low point
We grind the area until the dip is gone, then polish it with the floor.
Pro: It is flat, and it is still your own slab.
Con: That spot shows more rock and a different color.
Grind the whole floor to full aggregate
We cut the whole floor deep enough to flatten it.
Pro: It is often very pretty, with the same big rock everywhere.
Con: The rock mix, rebar depth, and extra densifier are a gamble. Plus materials.
Choice 1: leave low spots as they are
This is the default, and it adds nothing to your price, because we polish the floor and leave the dips alone. It is free and fast, and the rest of the floor still gets our full standard polish. The cost is in the look. Each low spot stays dull next to the polished floor, and you can see it from across the room when the light hits it, while dirt can sit in a deep boot print and make it look darker over time.
What does hand-polishing the low spots do?
We polish each low spot by hand with flexible pads that bend down into the dip, where the big machine cannot reach. It costs $67 per hour, counted by the crew hour, and the time depends on how many spots your floor has and how deep they go.
- Pros: The low spots get shine, so they look closer to the rest of the floor. A shined spot is also easier to clean than a dull one.
- Cons: The dip stays a dip. You can still feel it, and low light from the side will still show it.
Can you cut out, fill, and polish a low spot as a patch?
We cut the low spot out, fill it with patch mix, and polish it flat with the floor. It costs $67 per hour, counted by the crew hour, plus materials.
- Pros: The spot is flat. You will not feel it underfoot or see a shadow in it.
- Cons: It looks like a patch. The fill is not the same concrete as your slab, so its color and texture will not match the floor around it.
This choice fits a deep boot print in a spot where people walk. Flat matters more there than color.
What happens when you grind the area down to the low point?
We grind the whole area around the dip until it is gone, then polish it with the rest of the floor. It costs $67 per hour, counted by the crew hour.
- Pros: The spot is flat, and it is still your own slab, not a patch.
- Cons: To reach the bottom of the dip, the high ground around it has to come down. That deeper cut shows more rock and a different color in that 1 area, so it can read as a patch of its own.
Choice 5: grind the whole floor to full aggregate
We cut the whole floor deep enough to flatten it, so the dips are gone everywhere at once. It costs $67 per hour, counted by the crew hour, plus materials.
- Pros: It is often very pretty. The whole floor shows the same big rock, so no one area stands out, and the floor ends up flat.
- Cons: It is a gamble on 3 things no one can see ahead of time. The rock mix may look plain. Rebar or a grade stake may sit close to the top. A deep cut also opens the slab, so it usually needs extra densifier.
This cut takes about 2 to 4 times the hours of our standard cut, and it is the slowest choice on this list. Read more on the cut depth page.
Which choice do most owners pick?
It depends on the room. In a shop or a garage, most owners leave the low spots or hand-polish them, because a dull spot does not change how the floor works. In a living room or a store, where people look at the floor, a patch or a local grind can be worth it.
If you are not sure, ask us to look at photos first. Lay a 10-foot straightedge across the worst spot and take a picture with a tape in the gap. ACI 117, the flatness standard most crews pour to, sorts slabs by that same gap under a 10-foot straightedge, so that one number tells us more than any description of the floor can.
These hours are not in your total
Your quote total covers the standard polish. Any choice here other than leaving the low spots is billed per crew hour as worked, plus materials where it says so. Your quote lists what you picked and what you left.
Where do the other defects fit?
Low spots are 1 of 4 groups on your quote. Holes, cracks, soft spots, and cut depth have their own pages. Start from the polished concrete slab defects guide to see all 4, or go back to your quote to make your pick.
