Foundation Crack Diagnosis 101

Cracks in a foundation can range from harmless settling to critical structural damage requiring immediate repair.

Vertical vs. Horizontal

• Vertical cracks that are less than one-eighth of an inch wide are often the result of minor soil settlement and are usually harmless.
• Horizontal cracks indicate that lateral pressure from the soil is pushing against the foundation wall.
• Diagonal cracks usually signal that the frame is twisting or that the foundation is settling unevenly.

Measurement Tools

• A crack width gauge is essential for monitoring the growth of any existing fissures over time.
• Laser levels can help determine if the floor joists are now sloping due to foundation movement.
• Water staining often accompanies foundation issues, so check for damp spots near the cracks.

Always contact a professional geotechnical engineer for a formal assessment of significant foundation damage.