When Is a Foundation Crack a Structural Concern?

How serious Are the Cracks In Your Foundation?

Is the foundation of your home in jeopardy?

Replacing a foundation can cost up to $40,000(Ouch!). So obviously no one wants to get to that point…

Any cracks can be troubling. At the very least, they can let in insects (termites can get in through a crack as narrow as 1/64 of an inch!) and allow radon entry. Water and moisture usually come through cracks as well. Once that happens, mold can result.Finished basements can be ruined.


Not all cracks are a structural concern.

 In fact, most foundation cracks are not a sign of structural damage.

when is a foundation crack a structural concernMost foundation cracks are settlement cracks. This means that the soil underneath your home has settled, or moved, in a way that now the weight of your home is distributed unevenly on the foundation.This unbalanced pressure can cause cracks in the foundation walls and floors.

Settlement cracks in a poured concrete foundation are typically:

  • Vertical in nature
  • Thin (no wider than 1/4 of an inch)
  • Level on each side

Settlement cracks can become a structural concern if:

  • They become wider than 1/4 of an inch
  • They continue to widen
  • One side of the crack becomes higher than the other
  • Shearing(one side of the crack doesn’t match the other side) occurs

If this becomes the case, it’s best to have a foundation expert take a look at your foundation. They can determine how serious the crack, or cracks, are and how best to fix them.  An injection of urethane or epoxy may be recommended, and, at times, metal pins to be inserted on each side of the crack.

Horizontal cracks in a foundation wall are almost always a structural concern. They are a likely a sign that the foundation walls are failing under the pressure of the surrounding soil. Of course, these walls are made to support this surrounding weight. But they may fail if additional, unanticipated loads are put upon the

foundation crack repair

These may include:

  • backfill around the foundation being compacted improperly or too soon
  • hydrostatic pressure against the foundation walls due to a high water table or poor drainage
  • heavy equipment operated too soon or too close to the walls
  • tree roots expanding too close to the walls increasing the surrounding soil pressure


What about foundation walls made from concrete, or cinder, block?

Concrete block foundations actually have more compression strength than a poured concrete foundation-meaning it can hold more weight on top of the foundation. But as far as lateral strength(pressure from surrounding soil against the walls), concrete block foundations are weaker. They often crack in the middle of the wall in a horizontal fashion and bow inward. This is a structural crack. If these walls crack in a stair-step manner (horizontal, then vertical, then horizontal), they are usually not a structural concern unless they are in combination with wall movement and horizontal and vertical cracks.

No matter what the situation is, foundation cracks should be repaired. Taking care of them early can save money and headaches later on.

Need help? Call us at 978-687-4195

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