What is the minimum grade fall away from foundation walls?

What is the minimum grade fall away from foundation walls?

• A. 2 inches within 5 feet
• B. 4 inches within 10 feet
• C. 6 inches within 10 feet
• D. 8 inches within 15 feet

Answer: (C)

Water around a foundation must slope away from the wall to shed water and protect the foundation. The required grading is a drop of six inches within the first ten feet from the foundation. That means at ten feet out, the soil should be six inches lower than right at the wall, creating a gravity-driven path for water away from the foundation. This helps prevent water intrusion, basement moisture, and related damage.

The other options don’t meet this standard. A small drop over a shorter distance isn’t enough, and a larger drop over a longer distance isn’t the specified minimum within the first ten feet. The rule specifies six inches within ten feet as the minimum.