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Rainwater tank size calculator

Find out the right rainwater tank size for your property, depending on your intended use and the number of people living there.

Rainwater tanks can store water for future use and help you to save money on your water bill.

If you are planning to use your rainwater tank as a stormwater management device to meet Auckland Unitary Plan rules, see our Stormwater device sizing tool.

What will you use the rainwater tank for? Outdoor activities (e.g. garden watering, car washing). Indoor non-drinking water only (e.g. toilet, laundry). Indoor non-drinking water and outdoor activities (e.g. toilet, laundry, garden watering). All water usage (e.g. drinking water, toilet, garden watering).

What size of roof area will contribute rainwater to the tank?

This is the estimated roof area with gutters that will collect water and distribute it into your rainwater tank.

m²

How many people live in your household?

Calculate rainwater tank size Reset

Rainwater tank size calculator

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