Every Detroit home develops cracks over time. Michigan’s clay soil, freeze-thaw cycles, and older housing stock make foundation movement inevitable — but not all cracks are equal. Here’s how to tell which ones need immediate attention.

Hairline Cracks (Low Concern)

Thin cracks less than 1/8 inch wide in poured concrete are typically shrinkage cracks that form as concrete cures. These are cosmetic unless they show water infiltration or widening over time.

Horizontal Cracks (High Concern)

Horizontal cracks in block or poured concrete basement walls are serious. They indicate lateral soil pressure — the wall is being pushed inward. This requires structural repair promptly.

Stair-Step Cracks in Block Walls (Moderate to High Concern)

Stair-step cracks following the mortar joints indicate differential settlement — one section of the foundation is moving more than adjacent sections. Severity depends on width and whether it’s progressing.

Diagonal Cracks from Corners (Moderate Concern)

Cracks at 45-degree angles from door or window corners are typically settlement-related. Single small cracks may be stable; multiple widening diagonal cracks indicate ongoing movement.

Vertical Cracks with Displacement (High Concern)

If one side of a crack is higher or lower than the other (displacement), the foundation has shifted differentially — this requires engineering assessment.

313 Foundation Fix provides free inspections throughout Detroit and Wayne County. Call (313) 751-9872 to schedule.

Learn more about our foundation crack repair, or see our foundation repair in Dearborn page.