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Average Grade Plane Calculator

This calculator determines the average grade plane elevation and can also clarify if a particular floor is considered a story above grade plane. Please refer to the blog post on this topic for an explanation of how the calculation is performed.

Instructions for the calculator:

1. For each segment, enter the elevation of each endpoint (Point 1 and Point 2). Enter the length of the segment.
2. Repeat for each segment around the perimeter of the building.
3. The Average Grade Plane calculation is displayed at the bottom.
4. If you are looking to determine if a particular floor is a story above grade plane, enter the elevation of that floor level and the floor level above.
5. The calculator checks these elevations against the 3 criteria and displays if the floor is a story above grade or not.