What the work is
Grind and seal is what it sounds like. Diamond grinding takes the slab back — lightly, to clean it up, or deeper, to open the aggregate — and a sealer goes over that. The color, the joints and the variation in the concrete stay visible, because they are the finish.
It suits two situations. One is a slab that is genuinely good-looking and sound, where a coating would be covering something worth keeping. The other is a budget: it is the cheapest of these finishes by a distance and it still gives you a floor that cleans.
What it does not do is hide anything. Stains that have soaked into the slab are still in the slab. Grinding removes the top of the concrete, so it takes shallow staining with it, but oil that has travelled down is not coming out and a sealer will make it darker rather than lighter.
It is also the finish that wants re-doing rather than repair. A sealer wears, particularly where tires turn. Re-sealing is a straightforward recurring job, and we would rather you knew that up front than discovered it in year three.
What is included
- Diamond grinding to the agreed level, edges cut in by hand
- Dust extraction at the machine
- A plain account of which existing stains will and will not come out
- Sealer applied to the ground slab
- Telling you what re-sealing will involve and roughly when
What is not
- Removing staining that has penetrated the slab. Grinding takes the surface, not the depth
- A uniform color. The concrete is the finish and concrete is not uniform
- Polished concrete, which is a different process with different machinery and a different price
What the ground here does to a slab
Gypsiferous soil and rock is one of the nine adverse construction conditions the Utah Geological Survey mapped across the St. George and Hurricane area, and Washington County publishes it as its own hazard layer. Where sulfate is present in the ground it attacks concrete itself.
That matters more for grind and seal than for any other finish here, because the concrete is what you are keeping. On an exterior slab in a mapped zone, the condition of the concrete is the first question, not the last one. Under the American Concrete Institute exposure classes, a soil sulfate test is what determines the mix a slab needed; sulfate-resistant cement is required at class S2 and above. We are not going to tell you your slab is failing, and we are not going to tell you it is fine. We will tell you what we can see.
What to ask anyone quoting this, us included
- How deep are you grinding, and what will that expose?
- Which of these stains are coming out, and which are not?
- What is the sealer, and how often will it want doing again?