The patterns that matter
Stair-step cracks through brick mortar joints. Cracks wider than a quarter inch, or wider at one end than the other. Gaps opening at the top corner of interior doorframes. Doors and windows that stick in the same spot year-round rather than seasonally. Floors that visibly slope — roll a ball and watch.
Hairline cracks in drywall corners and thin vertical cracks in a poured wall are usually normal curing and seasonal movement.
Start with drainage, not piers
Most residential foundation movement traces back to water: downspouts dumping at the wall, negative grading, or a plumbing leak under the slab. Fixing piers without fixing water means paying twice.
Hire in the right order
Independent structural engineer first ($400–$900, no repairs sold). Take their written scope to two or three repair companies and compare bids against the same specification. Confirm the workmanship warranty transfers to a future buyer.