According to the code, under which condition are footings required to be stepped?

According to the code, under which condition are footings required to be stepped?

• A. stepped footings are not permitted
• B. if the ground surface slopes more than one unit vertical to ten units horizontal or where necessary to change the top footing surface elevation
• C. only when necessary to change the top footing surface elevation
• D. only when the ground surface slopes more than one unit vertical to ten units vertical

Answer: (B)

Stepping footings follows the grade to keep the footing tops aligned and prevent differential settlement when the ground isn’t level. The code requires stepping if the ground slope is steeper than 1 vertical unit in 10 horizontal units, or whenever it’s necessary to change the top footing surface elevation to maintain a proper, even top surface along the footing line. This covers both challenging slopes and practical needs to adjust elevations. The other statements aren’t correct because stepping is allowed under certain slopes, not forbidden; stepping isn’t limited only to cases where the top footing elevation must change—the slope threshold itself triggers stepping; and the reference ratio uses horizontal distance (1:10), not a vertical-vertical comparison.

Stepping footings follows the grade to keep the footing tops aligned and prevent differential settlement when the ground isn’t level. The code requires stepping if the ground slope is steeper than 1 vertical unit in 10 horizontal units, or whenever it’s necessary to change the top footing surface elevation to maintain a proper, even top surface along the footing line. This covers both challenging slopes and practical needs to adjust elevations.

The other statements aren’t correct because stepping is allowed under certain slopes, not forbidden; stepping isn’t limited only to cases where the top footing elevation must change—the slope threshold itself triggers stepping; and the reference ratio uses horizontal distance (1:10), not a vertical-vertical comparison.