Foundation Cracks in the Upper Midwest: When to Worry & How to Repair Them

Your home’s foundation is essential to its stability, but in Minnesota, North Dakota, and South Dakota, harsh winters, expansive soil, and moisture fluctuations can put it at risk. If you’ve noticed foundation cracks, you may be wondering whether they’re minor or signs of a bigger issue.

Understanding foundation cracks when to worry will help you take action before more extensive foundation repair is needed.

Hairline Cracks

These thin, surface-level cracks appear in concrete foundation walls or floors. They are often difficult to notice but can develop over time.

Vertical Cracks in Foundation Walls

These cracks run up and down and are commonly found in poured concrete walls. They can vary in width and may expand due to shifting soil or seasonal changes.

Horizontal Cracks in Basement Walls

These cracks run side to side and are typically found in block basement walls. They can be long and continuous, forming parallel to the ground.

Stair-Step Cracks in Brickwork

These cracks follow a diagonal, stair-step pattern along mortar joints in brick or concrete block walls. They are often a sign of foundation movement or settlement.

If you’ve noticed any of these cracks in foundation, it may be time to repair foundation cracks before they worsen.

• Cracks are growing – If a crack increases in width or length, it suggests ongoing foundation movement that may worsen.
• Walls are bowing – Horizontal cracks with inward movement indicate that excessive pressure is being applied to your basement walls.
• Water is seeping through cracks – Leaking cracks in vertical, horizontal, or stair-step patterns can lead to basement moisture issues, mold, and further structural damage.
• Floors feel uneven – If you notice dips, slopes, or soft spots, your foundation may be shifting and affecting the subflooring.
• Doors and windows are sticking – Difficulty opening or closing doors and windows is often a sign that foundation movement is warping your home’s structure

Soil Composition & Its Role in Foundation Cracks

• Minnesota & North Dakota – Clay-rich soil expands when wet and contracts when dry, leading to seasonal foundation movement.
• South Dakota – A mix of sandy and loamy soils can lead to uneven foundation settlement over time.
• Floodplain Areas & River Basins – Homes near the Red or Missouri River often experience foundation moisture problems due to high water tables.

Weather Patterns & Their Impact on Foundation Cracks

• Freeze-Thaw Cycles – Long, harsh winters in MN, ND, and SD cause water in the soil to freeze and expand, putting pressure on foundation walls.
• Drought & Heavy Rainfall – Dry periods cause soil shrinkage, while sudden downpours erode soil around foundations.
• Spring Snowmelt – Melting snow saturates the ground, increasing hydrostatic pressure and leading to foundation cracks and water intrusion.

1. Cracks Expanding & Structural Weakness

Foundation cracks widen over time, making them harder and more expensive to fix. 

2. Increased Repair Costs

A minor foundation crack repair may be a simple fix now, but delaying it could lead to more extensive repairs, potentially doubling the cost as the damage worsens.

3. Basement Water Damage & Mold Growth

• High humidity levels in Minnesota and North Dakota make basements more prone to water through foundation cracks.
• Cracks allow moisture in, leading to mold and mildew.

2. Know Your Foundation Repair Options

• Foundation Piers – Ideal for stabilizing shifting foundations surrounded by expansive clay soil.
• Wall Anchors – Best for reinforcing basement walls experiencing bowing due to hydrostatic pressure.
• Basement Waterproofing – Prevents water from seeping through foundation cracks, reducing flood risk and mold growth.