Cracked foundation repair is a structural question when the crack is a symptom of something moving: a wall pushed in by soil, or a corner of the house sinking. This page is about telling those cracks apart and getting the right person to look at them. It doesn't cover sealing a crack to stop a leak.
Cracks that point to movement
Patterns that manufacturer Foundation Supportworks ties to foundation movement [1]:
- Stair-step cracks in brick or block, which it links to uneven settlement stressing the mortar joints
- Diagonal cracks in a poured wall running toward the upper corners, which it links to soil pressure
- A poured wall leaning in at the top, which it calls shearing
- Cracks paired with other signs, such as gaps at door and window frames, a floor pulling away from a wall, or a chimney separating
Angi notes that nearly all foundations have small cracks from normal settlement, and that these aren't a structural concern. It names large structural cracks, sinking foundations and bulging walls as the kind of damage that can make a home unsafe [2].
Track it before you call
Angi suggests marking any cracks you find and watching for changes over a few months, while also saying to get a pro to inspect promptly if you suspect a problem [2]. A simple record helps whoever inspects:
- Photograph the crack with a tape measure in the frame.
- Mark both ends with a pencil and write the date.
- Note doors or windows that started sticking.
- Check again after a season and photograph it again.
Engineer or contractor?
Structural engineers, home inspectors and foundation repair contractors all do foundation inspections, according to HomeGuide [3]. The difference matters. HomeGuide says a company offering a free inspection may be more likely to recommend repairs [3]. An engineer's report states whether the structure is sound and, if not, what repairs are needed [4]. HomeGuide also says to check with your building officials or lender about what an engineer's report must include [4].
For a crack that's widening or sits on a wall that's moving, an independent report gives you a fixed plan to price against. See foundation inspection for what an inspection covers.
What the repair usually is
The crack is rarely the whole job. If a wall is bowing, the fix is usually wall anchors, straps or braces, covered on our basement wall repair page. If part of the house has settled, it's usually push piers or helical piers. Ask the inspector to tie each crack to a cause.
Permits
Structural work usually needs a permit. Green Bay requires permits for structural house alterations [5]. Neenah lists foundation repair or replacement as needing a permit [6]. Kaukauna's code requires permits before repairs or alterations [7].
FAQ
Is a vertical hairline crack structural?
Often not. Angi says small cracks from normal settlement aren't a structural concern [2]. Still, have a crack checked if it's widening or you see other signs of movement.
Does a crack have to be disclosed when selling?
Wisconsin's Real Estate Condition Report asks sellers about known basement or foundation defects, including cracks, seepage and bulges [8].
What does an engineer cost?
HomeGuide lists a structural engineer's foundation inspection at $300 to $750 [4].
Get quotes
Tell us where the crack is and your town, and a local contractor can contact you about an inspection. Request a free quote.
We're a referral service, not a contractor, and independent contractors may pay us for referrals.
Sources
- Foundation Supportworks (manufacturer), Signs of Foundation Failure. https://www.foundationsupportworks.com/foundation-repair/signs.html. Supports: stair-step cracking from uneven settlement; diagonal cracks toward upper corners in poured walls; shearing walls; gaps at frames; floor gap; chimney separation.
- Angi, "How Much Does Foundation Repair Cost? [2026 Data]," updated Oct 26, 2026. https://www.angi.com/articles/how-much-does-foundation-repair-cost.htm. Supports: small cracks from normal settlement not a structural concern; large structural cracks, sinking, bulging walls can make a home unsafe; mark cracks and watch for changes; have a pro inspect immediately.
- HomeGuide, "How Much Does a Foundation Inspection Cost?," Feb 5, 2026. https://homeguide.com/costs/foundation-inspection-cost. Supports: engineers, home inspectors and repair contractors all conduct inspections; free inspections may be more likely to recommend repairs.
- HomeGuide, "How Much Does a Structural Engineer Cost?," Dec 1, 2025. https://homeguide.com/costs/structural-engineer-cost. Supports: report states if structurally sound and what repairs are needed; contact building officials or lenders about report contents; foundation inspection $300 to $750.
- City of Green Bay, "Do I Need a Permit?" https://www.greenbaywi.gov/977/Do-I-Need-a-Permit. Supports: House Alterations (Structural): yes.
- City of Neenah, "When Do I Need a Building Permit?" https://www.ci.neenah.wi.us/wp-content/uploads/2024/04/When-Do-I-Need-a-Permit.pdf. Supports: foundation repair or replacement.
- City of Kaukauna, Building Inspection. https://www.kaukauna.gov/building-inspection/. Supports: Municipal Code requires permits prior to making repairs, alterations or improvements.
- Wis. Stat. 709.03, item B7. https://docs.legis.wisconsin.gov/document/statutes/709.03. Supports: defects in the basement or foundation (including cracks, seepage, and bulges).