A vertical foundation crack runs up and down a foundation wall, commonly caused by normal concrete shrinkage as it cures, or by minor, even settling of the foundation beneath it. These cracks are usually less concerning than horizontal or diagonal cracks, though width and consistency still matter when assessing them.
Vertical cracks are also the most common type found during a home inspection, simply because concrete shrinkage happens to some degree in nearly every poured foundation.
What Does a Vertical Foundation Crack Indicate?
- Normal concrete shrinkage during curing
- Minor, even settlement of the foundation
- Occasionally, early signs of more significant movement if widening
- Generally lower risk than horizontal or stair-step cracks
Why Are Vertical Foundation Cracks Important?
Most vertical cracks under about an eighth of an inch wide are simple shrinkage cracks that pose no structural threat and can often be sealed rather than structurally repaired. That said, a vertical crack that’s noticeably widening, especially if it’s wider at the top or bottom than the middle, can indicate settling that deserves a closer look rather than being dismissed automatically as harmless.
Sealing a vertical crack promptly, even a minor one, is still worthwhile since an unsealed crack can become an entry point for water and eventually contribute to a larger moisture problem inside the wall. A qualified inspector will typically also look at whether a vertical crack lines up with other clues, like a nearby window that no longer opens smoothly, before concluding the crack is purely cosmetic shrinkage.
Vertical Foundation Crack vs. Diagonal Foundation Crack
A vertical crack runs straight up and down, typically from shrinkage or even settling. A diagonal crack runs at an angle and more often signals differential settlement, where one part of the foundation has moved more than another, making it generally the more concerning pattern.