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)

This question tests the requirement that ground around a foundation must slope away to keep water from pooling against the wall and seeping into the structure. The minimum fall from the foundation should be six inches over the first ten feet, so the ground drops enough to reliably channel rainwater away. This distance and amount of slope help reduce hydrostatic pressure against the foundation and minimize moisture problems that can lead to leaks or frost issues. Why the other options aren’t the minimum: a smaller drop within the same or a shorter distance doesn’t meet the standard needed to ensure effective drainage, while a larger drop in a longer distance exceeds the minimum and isn’t the stated requirement.

This question tests the requirement that ground around a foundation must slope away to keep water from pooling against the wall and seeping into the structure. The minimum fall from the foundation should be six inches over the first ten feet, so the ground drops enough to reliably channel rainwater away. This distance and amount of slope help reduce hydrostatic pressure against the foundation and minimize moisture problems that can lead to leaks or frost issues.

Why the other options aren’t the minimum: a smaller drop within the same or a shorter distance doesn’t meet the standard needed to ensure effective drainage, while a larger drop in a longer distance exceeds the minimum and isn’t the stated requirement.