The short answer
Common Causes
Soil movement is the usual culprit. Clay soil expands when wet and shrinks when dry, and this constant shifting puts stress on the concrete. If water pools around the foundation after rain or irrigation, the soil becomes unevenly saturated, which can lead to differential movement and cracking.
Tree roots can also pull moisture from the soil, causing it to dry and shrink in spots. Plumbing leaks under the slab add water in other areas. Temperature swings make concrete expand and contract, and over time, hairline cracks widen. Even small cracks can let water in, which then freezes and expands in colder climates, but in warmer regions, the main issue is often soil movement.
- Cracks wider than a quarter inch
- Cracks that keep growing over months
- Doors or windows that stick
- Gaps between the foundation and walls
- Sloping or uneven floors
- Water pooling near the foundation
Check Water Flow First
Water is the main driver of foundation movement. Look at your gutters, downspouts, and the slope of the ground next to the house. Water should drain away from the foundation, not sit against it. Check that the soil slopes away from the house for at least six feet, and consider extending downspouts to carry water farther from the foundation.
A leaky hose bib, sprinkler, or underground pipe can add moisture to the soil. If you suspect a leak, turn off the water and watch the area. A plumber can test the line. Fixing drainage and leaks often stops new cracks from forming. Also, check the grading around the house after heavy rain to see where water collects.
When to Call a Pro
You can patch small, stable cracks with concrete caulk, but larger or growing cracks need a structural look. A foundation contractor or a structural engineer can measure the crack and check the soil conditions. They will tell you whether the issue is cosmetic or serious.
If you have water damage inside the home, like damp walls or a wet crawl space, local water damage pros can help dry things out and prevent mold. They handle cleanup after a leak or flood, not the foundation repair itself. Water damage can weaken the soil further, so addressing it early is important.
Repair Options
Repairs depend on what is causing the movement. For minor cracks, epoxy injection or polyurethane foam can seal the gap. For settling or heaving soil, the pros might install piers or adjust the foundation with hydraulic jacks.
If drainage is the issue, regrading the soil and extending downspouts can help. Sometimes, interior water damage from a cracked foundation, like a wet crawl space, needs drying and flooring removal. A water-damaged flooring removal service can handle that part. Keep in mind that repairs can vary widely in cost, depending on the extent of the damage and the method used.
Prevent Future Cracks
Keep the soil moisture consistent around the foundation. Water deeply but less often, and avoid letting the ground dry out completely. Maintain a slope of at least 6 inches over 10 feet away from the house.
Inspect your gutters and downspouts each season. Plant trees far enough away so roots do not reach the foundation. Keep your shutoff valve location written down so you can stop a leak quickly. Regular maintenance can save you from bigger problems later.
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Water keeps spreading into floors and walls, so it is worth acting early. Calls are answered 24/7.
Call Now (480) 898-4279Frequently asked questions
Is a small crack in my foundation a big problem?
Hairline cracks under 1/8 inch are often just shrinkage and not urgent. But if the crack widens, changes direction, or lets water in, it deserves attention. Watch it over a few months and note any changes before deciding on a fix.
Can I fix a foundation crack myself?
You can fill a stable, non-structural crack with a flexible concrete caulk. For larger or growing cracks, a structural professional should assess the cause. Doing a temporary patch is fine, but it will not stop the movement if the soil or water issue remains.
Will my insurance cover foundation cracking?
Policies vary, and your insurer decides what is covered. Foundation damage from a sudden plumbing leak might be covered, while gradual settling often is not. Check your policy and talk to your insurance company about the specific cause before making repairs.