What is the recommended slope around foundations for proper drainage?

The recommended slope around foundations for proper drainage is a 6-inch fall within 10 feet. This guideline is designed to ensure that water drains away from the foundation effectively, preventing water accumulation that can lead to soil saturation and potential damage to the foundation.

A 6-inch slope within 10 feet translates to a 5% grade, which is generally accepted in construction practices. This gradient is steep enough to promote quick drainage while still being manageable for landscaping and maintaining soil erosion control. Proper drainage is critical in minimizing issues such as hydrostatic pressure against the foundation walls, which can lead to cracking, settling, and other structural problems.

While the other options may suggest adequate slopes, they either fall short of the ideal drainage requirement or may introduce complications in maintaining proper landscaping practices.