Key takeaways
- Short answer: Hairline cracks (under about 1/8 inch) are common and usually caused by concrete shrinking as it cures.
- Hairline vertical cracks: usually normal
- Wider than 1/4" or growing: get it checked
- Horizontal or stair-step: likely structural
- Typical foundation repair cost: $2,176–$7,833 per typical project.
Crack types and what they mean
| Crack | Usually means | Action |
|---|---|---|
| Hairline vertical | Shrinkage | Monitor |
| Diagonal | Uneven settling | Monitor; engineer if growing |
| Stair-step in brick/block | Settling or soil movement | Engineer evaluation |
| Horizontal in basement wall | Soil pressure pushing in | Engineer soon |
| Wider than 1/4 inch | Active movement | Engineer evaluation |
How to monitor a crack
- Mark both ends with a pencil and write the date.
- Measure the width with a ruler or crack gauge.
- Photograph it with a coin for scale.
- Recheck every 1–3 months, especially after wet or dry spells.
Related questions
Should I seal a hairline foundation crack?
If it leaks water, an epoxy or polyurethane injection ($250–$800 per crack) seals it. Otherwise, monitor it.
Do new houses get foundation cracks?
Yes. Shrinkage cracks often appear in the first year or two.
Are cracks in drywall a foundation sign?
Sometimes. Diagonal cracks from door and window corners, plus sticking doors, can signal movement.
Other foundation repair questions homeowners ask
Are hairline cracks in a slab foundation normal?
Yes. Thin shrinkage cracks under about 1/8 inch are common in concrete. Wider cracks, cracks that grow or cracks with height differences need an evaluation.
How much does foundation repair cost?
A typical foundation repair costs about $2,176–$7,833. Piers usually cost $1,000–$3,000 each, so the number of piers drives the total.
How much does a structural engineer foundation inspection cost?
Engineer evaluations commonly cost several hundred dollars. It is worth paying for an independent opinion before hiring a repair company.
Does homeowners insurance cover foundation repair?
Usually not for settling, soil movement or wear. Coverage typically applies only when a covered event, such as a sudden plumbing leak, causes the damage.
Is foundation repair permanent?
Piers driven to stable soil or bedrock are designed to last the life of the house, but steady soil moisture and good drainage keep the rest of the slab from moving.
Should I buy a house that had foundation repair?
It can be fine if the work was engineer-specified, permitted and comes with a transferable lifetime warranty. Ask for the paperwork.
How do I protect my foundation during a drought?
Keep soil moisture steady with a soaker hose a foot or so from the slab, maintain gutters and grading, and keep thirsty trees away from the foundation.
How many piers does a house need?
It depends on how much of the house has moved. A corner might need only a few piers, while a whole side can need 10 or more. An engineer should set the plan.
Foundation Repair at a glance
Timeline
Pier installation usually takes 1–3 days. Wall stabilization and waterproofing take 1–5 days.
Permits
Structural foundation repair often needs a permit and an engineer's letter, especially for resale.
DIY or pro?
Grading, gutters and steady soil moisture are DIY prevention. Structural repair needs a licensed contractor and, ideally, an independent engineer.
What foundation repair costs
Foundation repair averages about $5,001, with most projects costing $2,176–$7,833. Simple crack repairs cost a few hundred dollars, while pier systems that lift and stabilize a home cost $1,000–$3,000 per pier.