Slab-on-Grade Foundation Crack & Settlement Inspection

Why it matters

Slab cracks indicate settling, water infiltration risk, or structural movement—early detection prevents $500–3000+ in epoxy injection repairs or floor damage. Unlike basement/crawlspace homes, slab homes have fewer inspection options; regular monitoring is critical.

How to do it

• 1

  Walk the interior perimeter of the slab (basement or main floor) and note any visible cracks.

• 2

  Inspect the exterior foundation line from the outside; look for new cracks or widening of existing ones.

• 3

  Use a ruler or caliper to measure any cracks >1/16 inch wide; document width, length, and direction (vertical, horizontal, diagonal).

• 4

  Look for stair-stepping patterns (cracks that follow mortar joints or step diagonally), which indicate settling.

• 5

  Note any wet spots, efflorescence (white powder), or damp patches on or near the slab.

• 6

  Take photos of all cracks; if >¼ inch or new, consult a structural engineer or foundation specialist ($300–500 evaluation).