Is it the public sidewalk along the street? The City of Huntsville says its Public Works Department maintains city sidewalks and repairs sections that become displaced or unsafe, so report it to the City first. For concrete on your own property, the rest of this page explains the repair.
Concrete problems that can be repaired
- Sunken slabs: a driveway panel that has dropped at the garage, a walkway that dips, a patio tilting toward the house.
- Trip edges: one panel higher than the next, an edge people can trip on.
- Cracks: cleaned out and sealed to keep water and weeds out.
- Surface scaling: flaking spots, often from de-icing chemicals or freezing water in a surface that wasn't air-entrained, or wasn't kept damp long enough while it hardened (cured).
Concrete leveling: mudjacking or foam
| Method | How it works | Cost per square foot |
|---|---|---|
| Mudjacking | A cement-based slurry is pumped under the slab through drilled holes. Heavier material, usually the lower price. | $4–$9 (HomeGuide, Nov 2025) |
| Polyurethane foam | Foam is injected through smaller holes and expands to lift the slab. Light, and sets quickly. | $8–$25 (HomeGuide, Nov 2025) |
| Slab jacking, either method | Fixr's range across all jobs | $3–$17 (Fixr, Jan 2025) |
Either way, find out why the slab sank. A downspout emptying beside the driveway or a gap at the edge where water gets underneath will undo a repair if it isn't fixed too.
When to replace concrete instead of leveling it
Leveling works on slabs that have sunk but are still in one piece. It isn't worth it when a panel is broken into several pieces, crumbling across its surface, or has sunk so far that lifting would crack it. Then replacing that section or the whole slab is the honest answer.
Why concrete sinks and cracks around Huntsville
- Clay over limestone. The Geological Survey of Alabama reports that much of Madison County sits on Fort Payne Chert and Tuscumbia Limestone, weathered near the surface into clayey soils and karst.
- Shallow rock in places. The U.S. Department of Agriculture's (USDA) description of Barfield soils, common in the county, puts limestone bedrock just 8 to 20 inches down. Shallow, clayey ground moves as it wets and dries.
- Sinkholes. A 2015 study presented to the Geological Society of America counted 460 moderate to large sinkholes and 547 caves in Madison County. A slab that keeps dropping in one spot deserves a closer look.
- Water. Downspouts and leaks that wash fine soil out from under a slab are the most common cause of all.
How to stop concrete damage getting worse
- Point downspouts away from slabs, or pipe them past the edge.
- Seal the gap where the driveway meets the garage floor and the house.
- Seal cracks before winter, when water in them can freeze.
- Keep de-icing chemicals off concrete, especially in its first winter (National Ready Mixed Concrete Association); sand gives grip without the damage.
Sources
- HomeGuide, Mudjacking Cost (November 5, 2025); Fixr, Concrete Leveling Cost (January 31, 2025)
- Geological Survey of Alabama, Hydrogeology and Regional Groundwater Movement in Madison County (2015; checked October 27, 2026)
- USDA NRCS, Barfield series official description (checked October 27, 2026)
- Geological Society of America, 2015 Annual Meeting abstract on Madison County karst
- National Ready Mixed Concrete Association, CIP 2, Scaling Concrete Surfaces (checked October 27, 2026)
- City of Huntsville, Sidewalks (checked October 27, 2026)