Rainwater Collection Tank Size Calculator
Size a rainwater tank from roof area, rainfall and demand.
Compare Your Options And Get Clear Answers
Size a rainwater tank from roof area, rainfall and demand.
Rainwater Collection Tank Size Estimator
Enter your numbers below for an instant estimate.
How It Works
Key concepts behind this calculator
Enter Values
Fill in each field with your own numbers.
Calculate
Results update as you change the inputs.
Review
Read the breakdown and the explanation.
Adjust
Change values to compare scenarios.
Rainwater Quick Guide
Typical values for reference.
| Roof | Annual yield | Tank | Use |
|---|---|---|---|
| 50 sq m | 28000 L | 2000 L | Garden |
| 100 sq m | 56000 L | 5000 L | Home |
| 150 sq m | 84000 L | 8000 L | Toilets |
| 200 sq m | 112000 L | 10000 L | Full |
| Rule of Thumb | Check inputs | Use as a guide | Round sensibly |
Rainwater Collection Tank Calculator FAQ
Answers to common questions about this calculator.
Enough to cover your demand through the longest dry spell.
It gives a quick estimate of rainwater collection tank size from the values you enter.
No. It is a planning estimate, so check important figures with a professional or official source.
Yes. Edit any field and the result updates when you calculate.
