Foundation (pin piles if geotech-required)

Two foundation worlds

Conventional spread footings on a flat, well-drained lot with cooperative soils: dig the footings, set rebar, pour concrete, set anchor bolts, strip forms. Three to four weeks. Cost is included in the GC's bid line.

Engineered foundation when the geotech requires it (steep slope, landslide-prone, peat, liquefaction): typically pin piles or helical piles driven to bearing, then a grade beam or pile cap connecting them. Specialty crew, longer schedule, $20,000 – $60,000 added.

The geotech report (step 1.3) tells you which world you're in. The structural engineer (step 2.3) designs to it.

Inspection

SDCI inspects after foundation forms and rebar are in but before concrete pours. A failed inspection here is a Friday-to-Monday-or-later setback because the inspector has to come back, and the GC can't pour with rebar exposed for days.

What can go wrong

• Soils don't match the geotech. Excavator opens the foundation hole and finds something different than the borings predicted. Triggers a geotech re-evaluation and possibly a redesign.
• Wet weather. Seattle. Foundations get pushed by rain. A 3-week foundation can become 5 weeks in November–February.
• Unmarked utilities. Utility as-builts are sometimes wrong. A surprise gas line, abandoned sewer, or fiber drop in the foundation area can stop work for days.

This is when the project becomes real

Up to this point you've been spending money on paper. From here on, the cottage is physically there. It's the moment most homeowners describe as the project finally becoming real.