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A drainage slope calculator determines the required grade for surface drainage and French drain systems. The minimum slope for surface drainage is 1–2% (1–2 inches per 10 feet); French drains require at least 1% slope (1/8 inch per foot). Inadequate slope causes standing water and foundation problems.

Stapsgewijze handleiding

  1. 1Input base values
  2. 2System computes results

Uitgewerkte voorbeelden

Invoer
Enter the required values
Resultaat
Result computed by the formula

Veelgemaakte fouten om te vermijden

  • Precision loss
  • Ignoring variables

Veelgestelde vragen

What does this calculator do?

Input base values

How do I use this calculator?

System computes results

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