Every spring the driveway gets the same look. A crack you swear wasn't there in October. The slab by the garage holding a puddle. Salt flaking near the street.
One contractor says replace it. Another says resurface. Your brother-in-law says caulk it and forget it.
They might all be partly right, because your driveway isn't one thing. It's eight, ten, or a dozen separate slabs divided by joints. A driveway with two bad slabs is not a bad driveway.
This guide is about what to do, not what it costs. For prices, see driveway repair cost.
Survey After the Frost Is Out
Much of the Green Bay area sits on red, clay-rich glacial soil, which is about as frost-susceptible as soil gets. It pushes slabs up in winter, then thaws from the top down and holds meltwater in spring. WisDOT's spring thaw weight limits run, on average, from about March 9 to May 9. Judge the driveway after that, in late May or June, on a dry day, then again after a good rain.
Bring: a tape measure, a 4-foot level or straight board, a screwdriver, a wooden-handled hammer, a garden hose, painter's tape, and your phone.
Number the slabs from the garage toward the street, left to right. Call the apron "A." If a public sidewalk crosses the driveway, note those panels separately.
The Decision Tree: Five Questions, in Order
1. Is the base moving?
Lay the level across every joint and measure any drop at the low side. Step on each corner. Tap with the hammer handle and listen for hollow spots.
- Lower than its neighbor, rocks, or tips toward the garage: the soil under it settled or washed out. That's a lifting candidate. Go to question 2.
- Higher than its neighbor: worse in March and better by June points to frost heave, a drainage fix first. Rising a bit more every year near a tree points to roots. See frost heave vs. settling and tree roots lifting concrete.
- Not moving: go to question 2.
2. Is it broken into pieces?
Count the pieces in each slab. One crack across the middle leaves two pieces, and if they sit tight together, that slab can usually still be lifted. Hairline cracks don't count.
- Four or more pieces, chunks that rock on their own, missing corners, or crumbling edges: replace that slab.
- One to three big pieces that sit tight: keep going.
3. Does water drain the right way?
Run the hose at the garage end and watch. The International Residential Code, a national model code, wants paved surfaces within 10 feet of a building to fall away from it at least 2 percent, about 1/4 inch per foot. A 4-foot level pointing away from the garage should show about an inch of drop.
- Water runs toward the garage because the slab sank: lifting restores the pitch.
- Water runs toward the garage but the joints are flush: it was probably built that way. Lifting can't lower the high end, and a garage approach can only come up as far as the garage floor. That's a replacement or drain conversation.
- Drains fine: go to question 4.
4. How much of the surface is damaged?
Drag the screwdriver hard across a flaky area. A scratch over hard concrete means the damage is at the surface. If it gouges, crumbles, or digs out sand and stone, it goes deeper.
- A few spots: clean, seal, and live with it.
- Flaking across most of the slab, hard underneath: a resurfacing candidate, or clean, seal, and accept the look.
- Soft and crumbling, or closely spaced curved cracks along a joint with dark staining: the second is D-cracking, freeze-thaw damage inside the stone (what it looks like). Replace.
5. How old is it, and what are your plans?
Age is a tiebreaker, not a verdict.
- Young and falling apart: something likely went wrong at the pour. Call the installer about their warranty first.
- Old but scores well: keep it.
- Old, borderline, and you plan to widen or reroute: replacement may make more sense, since repair money won't carry into a new layout.
The Slab-by-Slab Worksheet
Score each slab 0 to 3 in four categories:
| Score | Position | Pieces | Surface | Water |
|---|---|---|---|---|
| 0 | Flush with its neighbors (under 1/4") | One piece, hairlines only | Hard and smooth | Drains away, dries fast |
| 1 | Lip of 1/4"–1/2", doesn't rock | One tight crack | A few flaky spots | Small puddle that dries in a few hours |
| 2 | Sunk 1/2" or more, rocks, or tips toward the house | Two or three big pieces that sit tight | Flaking across most of it, hard underneath | Ponds or runs at the garage because it sank |
| 3 | (Use the H flag) | Four or more pieces, loose chunks, crumbling edges | Soft, crumbling, or D-cracking | Built to run the wrong way, joints flush |
Add two flags: H if the slab sits higher than its neighbors, and J if the joints around it are open, empty, or weedy.
Copy this onto paper with a line for every slab:
| Slab | Position | Pieces | Surface | Water | Flags | Outcome |
|---|---|---|---|---|---|---|
| 1 | ||||||
| 2 | ||||||
| A (apron) |
Reading the scores (a rule of thumb, not a law):
| If the slab has... | The outcome is... |
|---|---|
| Any 3 | Replace that slab |
| Position 2, nothing above 2 elsewhere | Lift it, then caulk its joints |
| Surface 2, Position 0–1 | Clean and seal; resurface if the look matters |
| All 0s and 1s | Clean, caulk open joints, seal |
| An H flag | Figure out frost or roots before anything else |
| A J flag | Caulk those joints, whatever else happens |
Then count the 3s. If only a few slabs need replacing, especially in one area like the apron or a corner, go with a mixed approach. If more than about half score a 3, full replacement is usually the better use of your money. In between, question 5 decides.
Worked Example: A 1990s Two-Car Driveway in Green Bay
Picture a driveway 20 feet wide and 44 feet long: two slabs across, four rows deep, each about 10 by 11 feet, plus a 20-by-8-foot apron. About 1,040 square feet in all.
| Slab | Position | Pieces | Surface | Water | Flags | Outcome |
|---|---|---|---|---|---|---|
| 1 (garage, left) | 2 (down 1-1/4" at the garage floor) | 1 | 1 | 2 | J | Lift, caulk |
| 2 (garage, right) | 2 (down 3/4") | 0 | 1 | 2 | J | Lift, caulk |
| 3 | 0 | 0 | 1 | 0 | J | Caulk, seal |
| 4 | 0 | 1 | 1 | 0 | Seal | |
| 5 | 1 | 0 | 2 | 0 | Clean, seal, watch | |
| 6 | 1 | 3 (five pieces over an old sump line trench) | 1 | 1 | Replace | |
| 7 | 0 | 0 | 1 | 0 | J | Caulk, seal |
| 8 | 0 | 0 | 1 | 0 | Seal | |
| A (apron) | 1 | 2 | 3 (salt and plow damage, crumbling) | 1 | Replace, with a city permit |
Two lifts, two replacements, caulk and sealer on the rest. Slab 6 and the apron total about 270 of the 1,040 square feet, roughly a quarter of the concrete. That's a mixed job, not a new driveway. Just fix the settled trench under slab 6, or its replacement sits on the same soft spot.
Slabs That Get Replaced
Any slab scoring a 3, plus whole driveways where most slabs do, slopes that were built wrong, and new layouts. Wisconsin points to raise with the concrete contractor:
- Why did it fail? A settled trench, a downspout dumping at the edge, soft fill. Fix it or the new slab follows the old one down.
- Air entrainment. Industry guidance calls for about 6–7 percent entrained air in concrete facing severe freeze-thaw with typical stone sizes. Ask for it by name.
- Thickness. Green Bay's driveway page asks for a surface that carries a 4,000-pound wheel load, which it says typically means 4 to 6 inches.
- Timing. Fresh concrete needs protection from freezing for roughly two days and shouldn't go on frozen ground. Plan on about a week before parking on it, and no deicers its first winter.
The full checklist is in questions to ask before replacing concrete.
Slabs That Get Lifted, Caulked, and Sealed
Slabs that sank but are still in one or two pieces, plus every slab with open joints or a dirty, lightly worn top. On a combined job, the work goes in this order:
- 1Clean the concrete and let it dry. See clean and seal concrete.
- 2Lift the sunken slabs through dime-sized holes, filling the voids and restoring the pitch away from the garage, then patch the holes. You can drive on it the same day. See how concrete lifting works.
- 3Caulk joints and cracks with flexible sealant so water stays out of the soil underneath. Polyurethane joint sealant takes about a week to fully cure. See driveway crack repair.
- 4Seal with a penetrating silane or siloxane sealer once the caulk has cured. It helps the surface shed water and salt, which slows further flaking.
What this won't do: erase cracks (they stay visible, just level and sealed), rebuild flaked areas, or save a broken-up slab. Chipped corners are a patching job for you or a concrete contractor.
Slabs That Might Get Resurfaced
A slab scoring 0 or 1 on position, pieces, and water, and 2 on surface, when you want it to look better.
Resurfacing bonds a thin layer of polymer-modified cement onto the old slab, typically from a feather edge to about 1/2". Outdoors in Wisconsin, it carries real risks:
- It's only as good as the concrete under it. Industry guidance on scaled concrete says a bonded repair is only as strong as its base. If the old surface is still shedding flakes, the overlay goes with them.
- Water at the bond line. Wherever the overlay isn't fully stuck down, water gets under it, freezes, expands about 9 percent, and pries it up.
- Salt. Deicer damage concentrates at the surface, and an overlay is nothing but surface.
- Cracks and joints come back through. One resurfacer data sheet we checked says reflective cracking can't be completely prevented and is more likely where the slab has settled. Joints have to be carried up through the new layer.
- A short season. The sheets we checked want air and concrete at 45–50°F or warmer. Green Bay's normal overnight lows don't clear 50°F until June and drift back toward it by September. It's a summer job.
- Height and prep. The added 1/2" shows up at the garage door seal, and one data sheet rules out sealed or painted concrete.
The honest alternative: flaking is usually cosmetic. Cleaning and a penetrating sealer can slow it for years at lower cost. Resurfacing is a looks upgrade, not a structural fix. More in pouring over existing concrete.
The Mixed Approach: Replace the Worst, Save the Rest
Joints make each slab its own piece, so replacing two doesn't mean touching the other eight. To do it well:
- 1Mark the plan on the slabs so every contractor bids the same job.
- 2Settle the target heights first. Either lift the keepers before the new slabs are formed, so new concrete matches the corrected heights, or pour first and lift the neighbors to meet it. Get both contractors to agree before anyone saw-cuts.
- 3Cut at the joints so the keepers don't get chipped, and ask whether new slabs will be doweled into the old ones or separated by an isolation joint.
- 4Fix what broke it. Reroute the sump line, repair the buried downspout pipe, compact the base.
- 5Expect a color difference. New concrete starts lighter. Cleaning the old slabs narrows the gap, but if a perfect match matters, that's a point for full replacement.
- 6Seal last. New concrete needs the cure time on the sealer label (often 14–28 days), and caulk goes in and cures before a penetrating sealer.
A Green Bay calendar for a mixed job:
| When | What |
|---|---|
| Late May–June | Survey, photos, quotes, apron permit. Call Diggers Hotline (811) at least three working days before anyone digs. |
| June–August | The easiest window for replacement pours, and the realistic one for resurfacing |
| Spring thaw to freeze-up | Lifting |
| 40°F or warmer, dry joints | Caulking, including seams between new and old |
| Late summer to early fall | Penetrating sealer, after caulk cures and new concrete passes its label cure time |
| First winter | No deicers on new slabs |
The Street Apron Is the City's Call First
In Green Bay, the city spells it out:
- The public right-of-way includes aprons, sidewalks, and curbs, including public sidewalk panels that cross your driveway.
- You or a contractor can resurface the driveway on your property, but not in the right-of-way.
- Building or rebuilding an apron takes a sidewalk builder licensed and bonded with the city, plus a Licensed Sidewalk Builders Permit from Public Works for each job.
- That permit sets the grade for your address. The new apron's height isn't your contractor's choice, so if the first driveway slab above it has sunk, plan on lifting it to meet the new apron.
Before spending money at the curb, call Green Bay Public Works (920-448-3100) and ask whether street or curb work is planned on your block. De Pere, Ashwaubenon, Howard, and Suamico set their own rules.