What we see across the city.
Bellingham is really two cities for a concrete crew. Up on the hills, off streets like Eldridge and around Sehome, you have older homes on glacial till with stepped footings and the occasional settling wall. Down in the flats near the bay and out toward the Lettered Streets, the ground is softer river-valley fill that moves with the seasons and cracks slabs that weren't isolated or reinforced. We work both ends of it every week.
The two problems we get called for most are failing post-and-pier crawlspaces under the older housing stock, and garage and basement slabs that were poured straight on dirt with no vapor barrier and now sweat all winter. Both are fixable. The crawlspaces get new concrete footings and steel posts; the slabs get torn out and re-poured over a real subbase and vapor barrier so they stop wicking moisture.
Common home styles
Craftsman bungalows and pre-war homes on the hills, mid-century houses east of I-5, and newer slab-on-grade construction in the developments on the edges of town.
Soil and water
Glacial till on the higher ground, soft fill and a high water table in the flats near the bay. Our rain keeps both saturated for months, which is why drainage is part of almost every repair we do here.