The answer typically falls between a third and half of the post's height and at least six inches below the frost line.
The line varies by latitude, it is deeper closer to the poles. The maximum frost depth observed in the contiguous United States ranges from 0 to 8 feet (2.4 m). Below that depth, the temperature varies, but is always above 0 °C (32 °F).
How much insulation do I need? In Mecklenburg County the insulation requirements are: R-19 in a floor above a crawl space or garage, R-15 in the exterior wall cavity or R-13 in the exterior wall cavity plus an R-2.5 continuous insulation and R-38 in the attic.
So the frost line in northern states would be deeper than here in the south. For example, the New England region has a frost line of 48 inches (that's a lot of digging)! The frost line in Mecklenburg County is approximately 12 inches (significantly less digging).
The coldest states, including Alaska, Minnesota, and North Dakota, have the deepest frost lines amongst all states. For instance, Alaska leads with an impressive 100-inch frost line depth, followed by Minnesota at 80 inches and North Dakota at 75 inches.
Yes, a Zoning Use Permit is required for structures 12 feet or less in any dimension. This permit assures that the structure is located far enough from property lines and other buildings/structures. A building permit is required for anything measuring over 12 feet in any dimension.
The frost line in Mecklenburg County is approximately 12 inches (significantly less digging). Soil depths below the frost line are relatively constant in temperature. Positioning mains below the frost line provides thermal insulation to the water line that helps prevent water from freezing within.
Yes, if this is your primary residence that you own, and you perform all the work yourself. Do I need a permit for a shed or “temporary” structure? Yes, a Zoning Use Permit is required for structures 12 feet or less in any dimension.