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Rainwater tank calculator for Wollongong

Wollongong averages about 1,128 mm of rain a year (long-term average at the Bureau of Meteorology’s Wollongong station). Every square metre of roof collects roughly 1 litre per millimetre of rain, so a typical Wollongong home can harvest a lot of water.

Rain you can collect in a year

Roof areaMetal roof (×0.9)Tiled roof (×0.8)Average per day (metal)
80 m²81,216 L72,192 L223 L
100 m²101,520 L90,240 L278 L
150 m²152,280 L135,360 L417 L
200 m²203,040 L180,480 L556 L
250 m²253,800 L225,600 L695 L
300 m²304,560 L270,720 L834 L

Work it out for your roof

The calculator below is pre-filled with Wollongong’s average rainfall. Change the roof area, daily use and tank size to match your home.

Your measurements

Rainwater tank calculator

Estimates only. Check sizes, coverage and quantities with your supplier, engineer or certifier before ordering. Standards references are a guide, not compliance advice.