Foundation Warning Signs You Should Never Ignore
A guide to the cracks, shifts, and structural tells that point to real foundation problems — and how to tell them apart from cosmetic cracks that can wait.
Updated April 17, 2026
Most homes have a few cracks. Most of them are cosmetic. But some cracks are the foundation telling you it's moving — and those don't get better on their own. This guide helps you tell the two apart and know what to do next.
Exterior signs to walk for
- Horizontal cracks in poured or block foundation walls — these point to lateral soil pressure and should always be evaluated.
- Stair-step cracks through mortar joints in brick or block — usually settlement.
- Chimneys that lean or separate from the siding.
- Gaps where the house meets the porch, deck, or attached garage.
- New gaps around window and door frames from the outside.
Interior signs
- Doors and windows that have started sticking or won't latch.
- Diagonal cracks running from the corners of door or window openings upward.
- Floors that slope noticeably, feel bouncy, or have soft spots near the middle of a span.
- Drywall cracks at seams or corners that reopen after patching.
- New cracks in tile floors — especially grout line cracks that keep appearing in the same spot.
Urgent vs watch-and-monitor
Urgent (call this week): horizontal cracks in block walls, bowing walls, active water entry, walls that have visibly moved inward, or doors/windows that have gone from fine to unusable in the last few months.
Watch-and-monitor: single vertical hairline cracks under 1/8 inch, minor stair-step cracks that aren't widening, cosmetic drywall seam cracks, small gaps at trim.
How to document
Take dated, in-focus photos straight at the crack. Include a coin or ruler for scale. Note the location on each photo. Check back in 30 days — if the crack visibly widened, that's movement, not just settlement.
What a Cornerstone foundation evaluation looks like
Nicholas walks the full perimeter outside, reads the soil and drainage, goes into the basement or crawl, and measures cracks where they matter. If nothing needs doing, we tell you that. If something does, you get a written explanation of what's happening and what it takes to fix it — no scare tactics, no inflated scope.
Call (812) 850-5320 to get a free evaluation scheduled.