I have a poured basement foundation on a 1920s home in the pacific northwest (zone 8). We've had a few cold winters, and there are signs of frost heave in the concrete around the house. The walkway, for instance, is all busted out and unlevel.
More urgently, I noticed recently the basement wall is pitched inward, about 1/2" per 4'. Also the forms are not totally level. I did not notice this before (lived here 6 years). Yet, I did not see any evidence of shear or stress fractures in the foundation. there are no cracks or signs of stress. Also the interior walls are not pitched at all.
Is it possible the house has settled with some geologic movement? Or the original pour is off? Is this any sign of danger, and what remediation would be considered?