Start with conditions, not a product
Cracks and sticking doors are clues, not diagnoses -- and near Concord, Piedmont red clay means soil moisture, grading, drainage, framing, and foundation type have to be considered together first.
Build a complete scope
- What was measured and over how long before a cause was assigned
- Whether the structure sits on mill-era piers, postwar block, or new fill
- Where storm water collects against the wall on a rolling lot
- The repair specified, and the options weighed and rejected
- Access, restoration of grade and finishes, and the warranty in writing
Concord context
Concord's three housing eras fail in three different ways, and identifying which one a house belongs to is most of the diagnosis. Mill-era and older in-town properties typically sit on brick or stone piers and unreinforced perimeter walls, where movement shows as sagging floors and separated piers rather than a single crack. Postwar houses are usually block crawl-space walls, vulnerable to lateral pressure from uphill water on these rolling lots. The newest subdivision construction is on engineered fill, which raises different questions about compaction and about the age of the fill. Beneath all three, Piedmont clay swells when wet and shrinks when dry, which is why movement in Concord is frequently seasonal rather than progressive -- and why measuring across a full wet-and-dry cycle before committing to piers is often the more economical decision.