On a typical garage floor coating job, hairline through 1/4-inch cracks are already included in our per-square-foot price. Larger cracks, spalled areas, and control joint blowouts run $50 to $200 per repair depending on size. Here is what's baked in, what's extra, and why.
Crack repair is the line item that surprises homeowners most often, because nobody talks about it on the first phone call. I'd rather show you the math up front than surprise you after the walk-through.
Why does crack repair matter before coating?
Concrete moves. Every slab in Wisconsin moves every winter because of freeze-thaw. If we coat over a crack without repairing it first, the crack telegraphs through the coating within 2 to 3 seasons. Worse, active cracks let moisture in, which can blow the coating off from underneath.
Proper crack repair stops the crack from mattering. We chase it out, fill it with TerraMend, which is a polyurea-based flexible repair product rated from -20 degrees Fahrenheit to 130 degrees Fahrenheit, and re-grind flush. Then the coating goes over a structurally stable surface. The crack is still there under the floor - it just doesn't move the floor anymore.
More about the cold-climate side of this in garage floor coatings in cold climates.
What's included in the base coating price?
Standard scope on every quote:
- Hairline cracks (up to about 1/16 inch wide)
- Stress cracks up to 1/4 inch wide
- Surface map cracking (crazing)
- Control joint prep and fill
- Minor surface pitting and pop-outs up to coin-sized
On a standard 450 sqft 2-car garage, most homes have 3 to 8 of these minor crack situations. All of them are baked into the $7 to $9 per square foot price. You do not see a separate line item for them.
What costs extra?
The situations that add to your quote:
- Cracks wider than 1/4 inch: $50 to $100 per crack depending on length. Needs deeper chase-out, sometimes backer rod, more TerraMend material
- Spalled areas the size of a dinner plate or larger: $75 to $150 per area. Needs a patching compound, cure time, and a re-grind
- Full control joint failure (edges broken out on both sides of the joint): $100 to $200 per linear run
- Corner breaks at garage door or slab edges: $75 to $150 per corner
- Rebar exposure: if we hit rebar during prep, the repair includes rust treatment and structural patch - $150 to $300
- Large heave cracks from frost: these are a bigger conversation. If a slab has a 1-inch vertical offset between sides of a crack, I might tell you the slab needs mudjacking or repair before I'll coat it
What does this look like on a real quote?
An average 2-car garage in River Falls, 18 years old:
Base coating price (450 sqft at $8/sqft): $3,600. 2 hairline cracks and 1 stress crack: included. 1 spalled area at the garage door threshold about 8 inches across: +$90. 1 control joint with a broken corner: +$75. Total: $3,765.
On this quote, the extra crack work added about 4.5% to the final price. That's typical. Most garages come in with $100 to $300 of extra repair work beyond the baseline.
When does crack repair push a slab past "worth coating"?
This is the honest answer most installers won't give you: some slabs aren't worth coating.
If your slab has more than about 15% of its area damaged - heavy spalling, multiple wide cracks, heave, exposed aggregate from surface failure - the repair cost starts eating the coating value. At a certain point, you're better off paying for slab replacement than trying to salvage a failing slab with $1,500 of patch work plus a coating.
I'll walk your garage and tell you straight if we're at that point. I've turned down jobs because I wouldn't put my warranty on a slab that wasn't structurally sound. That's rare - maybe 1 in 40 jobs - but it happens, and I'd rather say so than take your money on a floor that's going to fail.
Can you repair the cracks yourself before I come?
Please don't. I know it sounds like a way to save money, and I appreciate the instinct. But most hardware store crack fillers are incompatible with what we put down afterward. If you've filled a crack with the wrong product, I may have to grind it out and redo it, which adds time and cost.
If you want to help prep: sweep the garage, move everything out, get a dehumidifier running if the slab feels damp. Let me handle the cracks.
How I document repairs on the quote
When I walk your slab, I mark each significant repair with chalk and write them into the quote as line items. You see exactly where the extra money is going. If you want to see the slab before I leave, I'll walk you through every marked spot and explain what's happening there.
That's surface prep done honestly. More on it at surface prep and repair.
Bottom line on crack cost
- Most garages: $0 extra. Crack work is in the per-foot price
- Average aged garage: $100 to $300 extra for minor spalling and wider cracks
- Rough slab: $400 to $800 extra, still worth coating
- Badly damaged slab: consider replacement, I'll tell you if we're here
Get a free quote or call Dave at (715) 307-8302.