Residential Estimator automatically adjusts the foundation depth based on a foundation zone. The Residential Estimator has three standard foundation zones:
Mild: Foundation depth of 18".
Moderate: Foundation depth of between 30" and 42".
Extreme: Foundation depth of 54".
To use the default foundation zone displayed to the right, which is based on the ZIP/Postal Code, select Use Default here. The default zone displays in the "Defaults" column, and is based on the following map in the United States:
To set a different foundation zone, select one of the zones listed above. Residential Estimator also allows you to select Mild/Moderate and Moderate/Extreme.
Note: Residential Estimator does not adjust a basement foundation, since the basement wall extends below the frost line.