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Drainage falls · ratios · heights

Fall & Ratio Calculator

Enter a length and a designed ratio (or pick a preset from AS/NZS regulations) to get the required height drop.

Inputs
M
1 : N
Result
Required fall (height drop)
mm
Equivalent m
Gradient %
Per metre mm/m
Compliance awaiting input
Reference notes
Select an application and ratio to see the relevant AS/NZS guidance.