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Design tools
Rainwater tank sizer
Live BOM monthly rainfall, roof catchment and demand - monthly water balance for Carat, Platin and Sapphire bands.
catchment
Rainfall and roofs
BOM monthly rainfall and roof catchments. Your answers stay if you go back.
Enter your 4-digit postcode
Live BOM Climate Data Online monthly rainfall.
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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