You walked out to grab the mail and noticed it. A crack running across the driveway you swear wasn't there last month. Or maybe the corner of your pool deck is flaking off in chips the size of quarters. Or one panel of your front walkway has dropped an inch below the next one, and now it's a trip hazard every time the grandkids visit.
Take a breath. We get calls like this every single week here in St. Pete, and most of the time the fix is far less dramatic than the photos suggest.
We've been doing concrete repair across Pinellas County since 2017. In that time we've seen the same handful of problems show up over and over, mostly because Florida concrete lives a harder life than concrete almost anywhere else in the country. Salt air, sandy fill, a water table that sits two feet under your slab, mature oak roots, summer storms that dump four inches of rain in an hour. Concrete here ages on fast forward.
This guide walks through what we actually see, what causes it, what you can handle yourself, and what needs a professional crew before it gets worse. By the end you'll know whether to grab a tube of crack filler from the hardware store or pick up the phone.
The 5 most common concrete problems we fix in St. Pete
Almost every repair call we run falls into one of five buckets. Here's how to tell them apart.
1. Spalling (surface flaking and chunks popping off)
What it looks like: Pieces of the top layer of concrete breaking off in flakes, chips, or sometimes fist-sized chunks. Often you can see rust stains underneath, or actual rebar exposed in the worst cases. Most common on pool decks, seawalls, driveways near the coast, and the bottoms of porch columns.
What causes it: Salt air. This is the big one in St. Pete, especially if you live anywhere near the water. Coquina Key, Snell Isle, anything along Tampa Bay or the Gulf side. Salt particles ride the breeze inland, soak into the concrete through hairline cracks and worn sealer, and reach the steel rebar buried inside. Once the rebar rusts, it expands to about seven times its original volume. That expansion blows the concrete apart from the inside. You're seeing the symptom on the surface, but the damage started two or three inches down.
Can you DIY: Small cosmetic spalling on a non-structural surface (a few flakes on a pool deck) can be patched with a polymer-modified concrete repair mortar. Anything where you can see rust or rebar, no.
When to call: As soon as you see exposed steel, rust bleeding through the surface, or chunks bigger than a golf ball. Spalling never gets better on its own. Every week you wait, more water and salt reach the rebar.
Repair cost range: Small patch jobs run $300 to $700. Larger sections with rebar treatment and resurfacing typically run $1,200 to $3,500 depending on square footage.
2. Scaling (the top layer peeling like sunburn)
What it looks like: The top eighth of an inch of concrete flaking off in thin, papery sheets. The surface feels rough and sandy where it used to be smooth. Often shows up first in the spots that get the most sun, like the south-facing edge of a driveway.
What causes it: Two things working together. First, the original surface sealer broke down. Most builder-grade sealers in Florida give up in three to five years under our UV. Once the sealer is gone, rainwater and irrigation water soak straight into the top layer. Add chloride from salt air or pool chemicals, and the surface starts coming apart.
Can you DIY: Cleaning and resealing with a quality penetrating sealer can stop scaling that's just starting. Once the surface is already peeling, you need resurfacing.
When to call: When more than 20% of the surface area is affected, or when you can feel loose grit underfoot across most of the slab.
Repair cost range: Resurfacing with a polymer overlay runs $4 to $8 per square foot. A typical driveway falls between $1,800 and $4,000.
3. Hairline cracks (mostly cosmetic, mostly fine)
What it looks like: Thin cracks less than the width of a credit card, usually running in random patterns or following the control joints. Concrete shrinks as it cures, and these are almost always shrinkage cracks from the original pour.
What causes it: Normal concrete behavior. Every slab in Florida has them within the first year. Heat, humidity swings, and our heavy summer rains accelerate the appearance, but they're rarely a structural concern.
Can you DIY: Yes. A tube of polyurethane crack sealant from any hardware store, a putty knife, and twenty minutes will keep water out of the crack and stop it from widening. Clean the crack with a wire brush first, blow out the dust, then run the sealant in.
When to call: If a hairline crack starts widening, lengthening, or showing a vertical offset where one side sits higher than the other. That means it's no longer cosmetic.
Repair cost range: If you'd rather have us seal them, $200 to $400 for a typical residential job.
4. Structural cracks (call immediately)
What it looks like: Any crack a quarter inch or wider. Stair-step cracks running through a foundation block wall. Horizontal cracks in a slab or wall. Cracks where one side has dropped or lifted relative to the other. Cracks that leak water during rain.
What causes it: Real movement. Could be settlement under the slab, sinkhole activity (parts of Seminole and Largo sit on karst geology that's prone to this), hurricane wind load on an older slab, root pressure from a mature live oak, or a foundation problem you need a structural engineer to diagnose.
Can you DIY: No. Filling a structural crack without addressing the underlying movement hides the problem and lets it get worse.
When to call: Today. Take photos, measure the width with a ruler, note the date. If it's growing week over week, that's urgent.
Repair cost range: Epoxy injection on a contained structural crack runs $400 to $900 per crack. If the underlying cause requires foundation work, that's a separate scope.
5. Settlement and sunken slabs
What it looks like: A driveway panel sitting an inch lower than the one next to it. A sidewalk slab tilted toward the lawn. Pool deck sections that have dropped, creating a lip you can stub a toe on. Sometimes you'll see a gap opening up between the slab and the house slab.
What causes it: Sandy fill compacting over time, which is most Florida lots. Sometimes a buried tree root rotted out and left a void. Sometimes irrigation water washed fines out from underneath. Allendale and other 1950s neighborhoods see a lot of this because the original fill wasn't compacted to modern standards.
Can you DIY: No. Lifting a settled slab takes specialized equipment.
When to call: Any time the offset is more than half an inch, or any time it's a trip hazard.
Repair cost range: Concrete leveling with polyurethane foam runs $8 to $15 per square foot. Traditional mudjacking runs $300 to $600 per panel. Both are dramatically cheaper than tear out and replace.
DIY vs professional, where the line is
We'll be straight with you. Not every crack needs a contractor. Plenty of St. Pete homeowners handle their own cosmetic repairs and do a fine job. Here's the honest line we draw.
DIY is reasonable when the crack is hairline, the surface is otherwise sound, there's no offset between the two sides, no water intrusion, and the slab is non-structural (a sidewalk, a patio pad). Buy a quality polyurethane sealant, not the cheap latex stuff. Clean the crack properly. Apply on a dry day.
Call a professional when you see exposed rebar, any vertical or horizontal offset, cracks wider than a quarter inch, settlement, scaling across large areas, or cracks in load-bearing structures like garage slabs, foundation walls, or seawalls. Also call when you've patched the same crack twice and it keeps coming back. That means the underlying cause isn't being addressed.
Repair methods we actually use
Most repair work in St. Pete falls into four buckets. The right method depends entirely on the problem.
Epoxy injection is what we use on structural cracks in slabs, walls, and seawalls. We seal the surface of the crack with a paste, install injection ports every six to twelve inches, then pump a low-viscosity structural epoxy through the full depth of the crack. The cured epoxy is stronger than the surrounding concrete. When done right, the slab behaves as if the crack never existed.
Polyurethane foam leveling is our default for sunken slabs. We drill small dime-sized holes through the slab, inject expanding structural foam into the void below, and the foam lifts the slab back to grade as it expands. Cures in fifteen minutes. You can drive on it the same day. Lighter than mudjacking slurry, doesn't add weight to soil that already has settlement problems, and the holes patch invisibly.
Mudjacking is the old-school version of the same idea. We pump a cement and soil slurry under the slab. Heavier than foam, larger access holes, slightly cheaper. Still a solid option on larger jobs where the extra weight isn't a concern.
Partial slab replacement is what we do when the concrete itself is too damaged to save, but only in a defined area. Cut along control joints, remove the bad section, prep the base, pour and finish the new section to match. Color and texture matching takes experience. A bad partial replacement looks worse than the problem it fixed.
Surface resurfacing is a polymer-modified overlay we trowel over the existing slab. Good for fixing scaling, light spalling, and tired-looking surfaces. Can be stamped or stained to look like new. We use this a lot on pool decks and driveways that are structurally sound but cosmetically rough. If you want something fancier we can roll it into a stamped concrete finish at the same time.
What it costs
Pricing on concrete repair varies more than almost any other home repair category, because the same crack can be a $300 fix or a $3,000 fix depending on what's underneath. Here are realistic St. Pete ranges as of 2026.
- Hairline crack sealing: $200 to $400 for a residential driveway
- Epoxy injection for structural cracks: $400 to $900 per crack
- Polyurethane foam slab leveling: $8 to $15 per square foot
- Mudjacking per panel: $300 to $600
- Surface resurfacing: $4 to $8 per square foot
- Spalling repair with rebar treatment: $1,200 to $3,500 per section
- Full slab replacement: $8 to $15 per square foot installed
If anyone quotes you a flat number over the phone without seeing the work, get a second opinion. There are too many variables.
When repair won't cut it and you need replacement
Sometimes the honest answer is that the slab is past saving. We tell people this every month, and it's never fun. Here's how we know.
If more than 30% of the surface is spalling or scaling, you'll spend more patching than replacing. If the slab has multiple structural cracks running through it, the load path is compromised. If settlement has cracked the slab into three or four pieces, foam can lift it but the cracks will telegraph through any overlay. If the concrete was poured at the wrong mix ratio originally (we see this on a lot of investor-flip homes), no repair holds for long because the base material is weak.
A new slab in St. Pete runs $8 to $15 per square foot installed, including demolition, base prep, rebar, pour, and finish. If repair costs are creeping above 60% of replacement cost and the slab has more than one major problem, replace it.
Why FL concrete fails earlier than the rest of the country
Concrete in Phoenix lasts 50 years. Concrete in Cleveland lasts 40. Concrete in St. Pete starts showing problems at 15 to 20.
Here's why. Our chloride load is brutal. Salt air, irrigation water with high mineral content, pool chemicals, and rain that picks up salt off the pavement all attack the rebar inside the slab. Our water table is high, so the underside of every slab in the city sits in or near groundwater for at least part of the year. Sandy fill keeps moving. Tree roots from live oaks and palms run shallow and lift concrete from below. UV breaks down sealers in three to five years and then everything we just mentioned starts working on bare concrete.
None of this is fixable on a citywide level. But once you understand the conditions, you can stay ahead of them with maintenance. Reseal every three to five years. Address cracks while they're small. Keep irrigation heads from spraying directly onto the slab. Don't let mulch sit against the bottom of porch columns.
Sealing after repair, the only step everyone skips
Here's the part most homeowners and a lot of cheaper contractors leave out. After any concrete repair, the entire slab needs to be cleaned and sealed with a quality penetrating sealer. Not a cheap topical sealer that wears off in a year. A silane or siloxane-based penetrating sealer that soaks into the pores and blocks chloride and water from getting in.
Skip this step and you'll be doing the same repair again in five years. We've watched it happen. Customer pays for spalling repair, looks great for two summers, then the salt finds the next weakest spot in the rebar and you're back where you started.
Sealing a typical residential slab runs $1 to $2 per square foot and lasts three to five years. It's the single highest-value thing you can do for Florida concrete.
What happens next
If you're staring at a problem right now and you're not sure how serious it is, the fastest path is a free on-site assessment. We come out, look at it in person, tell you whether it's cosmetic or structural, and give you a real number. No pressure, no upsell. Sometimes we tell people to grab a tube of sealant and handle it themselves. That's fine. We'd rather build trust than push a job that doesn't need doing.
We work all over the St. Petersburg service area, from Snell Isle and Old Northeast down to Coquina Key, Skyway, and out to Seminole and Largo. Same-week assessments are usually available, and most repairs can be scheduled within two weeks.
Call Randy at 727-291-9908, or request a Free Estimate online and we'll get back to you the same day. Whatever the crack turns out to be, you'll know exactly what you're dealing with before you spend a dollar.
