PVC Drainage Pipe Calculator

Last updated: 2026-08-24

PVC Drainage Pipe Calculator — Size PVC sewer pipes using Manning's formula. Calculate flow capacity and velocity for gravity drainage systems.
Inputs
Result
Enter values and press Calculate

How to use it

  1. Calculate pipe length with 10% waste: 20m x 1.10 = 22m
  2. Calculate 3m lengths needed: 22m / 3m = 7.33 -> 8 lengths
  3. Calculate elbows: 4 branches x 2 = 8 elbows
  4. Calculate couplings: 20m/3m + 4 branches = 10 couplings
  5. Calculate tees: 4 branches / 2 = 2 tees

Common mistakes

  • ⚠️ Use slope inferior to the 1% (risk of obstrucción per sedimentación)
  • ⚠️ Instalar pipe of PVC to water caliente sanitaria without Verify temperature máxima (60°C)
  • ⚠️ Not prever registros of limpieza each 15 m in tramos rectos

Worked example

Calculate PVC drainage pipes for a 20m run with 4 branches.

For a {length}m run: {barras_3m} lengths of 3m pipe, {codos_ud} elbows, {manguitos_ud} couplings and {tee_ud} tees.

Input guide

FieldTypical range
longitudTotal length of drainage pipe run
tramosNumber of branch connections