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Drainage Calculator — Free Online Calculator

Calculates the length and number of drainage channels or pipes required.

What is it?

The guttering calculator works out the number of gutters, downpipes and outlets needed to drain rainwater from your roof.

Formula

Gutters = ⌈eaves length / section length⌉ Downpipes = ⌈house height / section length⌉ × number of drain points Outlets = number of drain points

Example

Eaves 30 m, house height 5 m, 4 drain points, 3 m sections. Gutters: ⌈30 / 3⌉ = 10. Downpipes: ⌈5 / 3⌉ × 4 = 8. Outlets: 4.

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