What do cracks, stains and old coatings add to the price?
Condition is the biggest reason two identical garages get different quotes — and the reason a real quote can land above a web estimate.
Why this is where quotes diverge
Almost every advertised garage floor price assumes bare, sound concrete. That is a reasonable thing to advertise and a poor thing to plan around, because the work that happens before any coating goes down — grinding, crack repair, degreasing, removing whatever is already there — is where the cost varies most between two floors of the same size.
The figures below are a 400 sq ft two-car garage with a standard flake finish, changing nothing but the state of the slab.
Slab condition
| Condition | Planning range | vs sound slab |
|---|---|---|
| Sound, no visible cracks Clean, flat, no movement. The assumption behind almost every advertised price. | $2,450 – $3,800 | baseline |
| A few hairline cracks Fine shrinkage cracks. Chased out, filled and ground flush before coating. | $2,450 – $4,100 | about +$150 |
| Sound but oil-stained Structurally fine, but contamination has to be degreased and drawn out or the coating will not bond. | $2,450 – $4,200 | about +$200 |
| Several noticeable cracks Wider cracks, some with lipping. Real repair labour before any coating goes down. | $2,500 – $4,500 | about +$400 |
| Pitting, spalling or large damage Surface has broken up or delaminated. Patching and resurfacing, and sometimes a question about whether coating is the right answer at all. | $2,850 – $5,450 | about +$1,050 |
What is already on the floor
Separate from the condition of the concrete is the question of what has to come off first. On the same sound 400 sq ft slab:
- Bare concrete: $2,450 – $3,800. Nothing to remove.
- Painted: $2,500 – $4,500. Garage floor paint is usually thin but rarely well bonded, and all of it has to go.
- An existing coating: $2,600 – $4,800. Published locally from about a dollar a square foot, with no reliable ceiling — a coating that is genuinely well bonded is slow, dusty work.
If you genuinely do not know
That is a normal answer, and it is better than a confident wrong one. Telling the calculator the condition is unknown gives $2,450 to $4,800 on the same garage — a wider band spanning minor through moderate repair, rather than a narrow number quietly assuming the best case.
If you want to narrow it before anyone visits: sweep the floor, look along it at a low angle in daylight, and note whether cracks are hairline or wide enough to catch a fingernail, and whether any area sounds hollow underfoot.
What none of this covers
Structural problems. A slab that is actively moving, heaving, or has cracks with a height difference across them is a foundation question, and no coating fixes it — the crack will telegraph through whatever goes on top. If that sounds like your garage, the right next call is a foundation assessment, not a coating quote.
Common questions
Can you coat a cracked garage floor?
Usually yes. Hairline shrinkage cracks and ordinary cracking are routinely chased out, filled and ground flush before the coating goes down, and once coated they are invisible. What cannot be fixed with a coating is active movement: a crack that is still opening, or one with a height difference across it, will eventually show through whatever is put on top. That is a slab question, not a coating question.
How much do oil stains add?
Less than most people expect, because staining is a contamination problem rather than a structural one. The floor is degreased and the contamination drawn out of the concrete before coating. It adds preparation time, not repair. What matters is that it is dealt with — a coating applied over oil-soaked concrete will not bond, and that failure shows up months later.
What if my garage already has epoxy on it?
It generally has to come off. Austin installers publish existing-coating removal at around a dollar per square foot and up, and the "and up" is the part to watch: a coating that is well bonded can cost more to remove than the new one costs to install. It is also the item most often quoted separately from the headline rate.
Should I fix the slab before getting quotes?
Not usually. Crack repair is part of a coating job and installers price it as such, so paying separately in advance often means paying twice for the same grinding. The exception is structural damage — if the slab is moving or heaving, that is a foundation question and a coating over it is money spent on a symptom.