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Rainwater Drainage and Roof Gutter Sizing

Roof drainage calculation, gutter sizing, downpipe sizing and rainfall intensity data.

rainwaterdrainagesizingCalculator

Overview

Engineering reference data for Rainwater Drainage and Roof Gutter Sizing in sanitary drainage.

Key Formulas

Manning's Equation

Q=1nARh2/3S1/2Q = \frac{1}{n} A R_h^{2/3} S^{1/2}

Open channel flow.

Slope

S=ΔhLS = \frac{\Delta h}{L}

Hydraulic gradient.

Variables

SymbolDescriptionUnit
QQFlow ratem³/s
nnManning roughness
AAFlow area
RhR_hHydraulic radiusm

References