Design tools
Rainwater tank sizer
Live BOM 10-year monthly rainfall average, roof catchment and demand - monthly water balance for Carat, Platin and Sapphire bands.
catchment
Rainfall and roofs
BOM 10-year monthly rainfall average and roof catchments. Your answers stay if you go back.
Uses the 10-year monthly rainfall average from the nearest BOM Climate Data Online station when 10 complete years are available. Shorter records show an N-year average instead.
Roof catchments
If BOM is unavailable, enter 12 monthly rainfall totals (mm) manually.
Results are indicative for early design only. Confirm sizing with a licensed plumber, hydraulic consultant, or GRAF Australia for site-specific conditions and council requirements.
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