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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.

Trin-for-trin guide

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

Løste eksempler

Input
Enter the required values
Resultat
Result computed by the formula

Almindelige fejl at undgå

  • Precision loss
  • Ignoring variables

Ofte stillede spørgsmål

What does this calculator do?

Input base values

How do I use this calculator?

System computes results

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