Foundation
Upheaval
in Maryland

Most foundation problems in Maryland are about the ground sinking. Upheaval is the opposite: a section of slab or footing pushing upward instead of settling down. It's less common than settlement, but it comes from the same clay soil behaving differently under different conditions.

Maryland's Piedmont clay swells when it absorbs water and shrinks as it dries out. Where drainage concentrates water against one section of a footing or slab, that clay can swell enough to push the concrete upward rather than settling it.

They're genuinely opposite movements, which is exactly why OBW distinguishes them rather than treating every foundation problem the same. A sinking foundation moves a whole section down as a coordinated unit, and it often shows little to no interior cracking, since the structure isn't racking or twisting. Upheaval pushes a section up, and it frequently does produce cracking, just in the reverse pattern of ordinary settlement: wider at the bottom, narrower toward the top. Both are read against a fixed reference, exterior grade for sinking, crack orientation and elevation for upheaval, rather than assumed from a generic checklist.

Shallow footings are also vulnerable to frost heave, expansion of soil moisture as it freezes below a footing that wasn't set deep enough to clear the frost line, roughly 30 inches in Maryland's climate. Both causes, clay swelling and frost heave, trace back to water and how it's managed around the foundation, not to a structural defect in the concrete itself.

Upheaval shows up as a slab or floor section that's noticeably higher than the surrounding area, cracks that are wider at the bottom and narrower toward the top, the reverse of the pattern typically seen with settlement, or doors and windows binding from a direction opposite what you'd expect from a sinking foundation. A free OBW foundation inspection measures the affected section and checks the drainage and grading conditions around it to confirm upheaval rather than settlement before recommending a fix, since the correction for each is different.

Because upheaval is driven by water reaching the soil beneath the foundation, correcting drainage and grading at that section is the first step. Addressing it without fixing the water source usually means the same movement returns after the next wet season. For slab specific upheaval, slab foundation repair addresses the affected section once the underlying moisture issue has been resolved. Backed by a written workmanship guarantee, terms vary by service, ask your inspector.