Tell him to lower the finished soil level so that the soil and any mulch are at least 6 inches below the bottom edge of your siding. Henrico County, Virginia, gives the same siding clearance in its residential inspection guidance. [Henrico County guidance](https://henrico.gov/bldg/residential-building/inspection-requirements__trashed/slab/)

Foundation height and siding clearance are separate measurements because siding sometimes overlaps the foundation. For houses with siding, the IRC calls for the top of a concrete or masonry foundation to sit at least 6 inches above finished grade. [ICC explanation of R404.1.6](https://media.iccsafe.org/news/icc-enews/2016v13n7/2015_res_essentials_p70.pdf)

The excavated area also needs to drain. Slope the soil away from the house, ordinarily dropping at least 6 inches over the first 10 feet. If the brick pad or property line prevents that slope, provide a drain or swale with an outlet. A narrow trench beside the foundation could become a trough that holds water. [IRC R401.3](https://codes.iccsafe.org/content/IRC2021P2/chapter-4-foundations)

For your snow conditions, I’d aim for 8 to 12 inches of siding clearance where practical to give you some extra margin. Six inches won’t protect against every snowfall, so keep piled snow away from that wall.

Since you already have substantial water damage, have the lower wall opened and inspected during the repair. Lowering the soil will prevent further burial, but damaged sheathing, framing, and flashing still need attention.