Paver Repair & Re-Sanding in China Township

The township's 2004 master plan, drawing on the county soil survey, places lake-plain clay and silt under most of China Township, with soils that drain poorly and hold a seasonal high water table. The same plan names frost heave among the reasons many gravel county roads come out of winter in poor shape. A patio rests on the same kind of ground.

Frost heave takes freezing weather, a frost-susceptible soil and water at once. As the cold works down, water wicks up toward it and freezes into ice layers that push the surface up. Silts are among the most prone soils, clay heaves less severely, and clean, drained gravel rarely heaves. The damage comes from uneven lift: a corner that stays wetter, beside a downspout or on the low side of the lot, can rise farther. Spring thaw runs top-down, so meltwater stays trapped in softened soil until the frozen layer beneath has thawed.

Not every low spot is frost. About 46% of the township's homes went up between 1990 and 2009, so a patio laid with one has seen 15 or more winters. CMHA, the paver industry's technical association, traces most dips to a base that settled, often from poor compaction; too-thick bedding and a saturated base are other causes. It wants at least 4 inches of compacted base under a patio or walk on well-drained soil and 6 under a driveway, more where soils stay wet. Lots near the Belle River valley or Beaubien Creek sit close to mapped wetlands and floodplain. Whether the pavers sit in White Pines Estates off King Rd or behind a home on Wadhams Rd, the repair starts with the layer that gave way. Drainage work is outside what we do; the estimate flags it when water is the cause.