Measuring flow rates
Old and inefficient taps and showerheads can run at a flow rate of between 15 and 22 litres of water per minute, while water efficient models use less than 9 litres per minute. But how do you know if the tapware you have installed is appropriate for your home?
If you have an old, inefficient showerhead, then upgrading to a new water efficient showerhead is a great way to save water and cut costs on your energy bills. There are however some circumstances when you should not upgrade to a water efficient model. These situations include when:
- You have a gravity fed hot water system
- You live in a location that has low mains pressure
- Your current showerhead may already be water efficient
In any of these situations, it is likely that your showerhead is already using less than 9 litres of water per minute. ;To find out for sure, you can pick up a flow rate test cup from you local plumbing supplier or do a simple bucket test, following the instructions in the video below.
Measuring flow rates using the bucket test
You will need a bucket, a timing device, and a showerhead or tap.
- Place a bucket under the showerhead or tap.
- Turn on both the taps to full flow.
- Run the water for 10 seconds before turning off, capturing all of the water in the bucket.
- Measure the amount of water captured.
- Multiply this amount by six to calculate the flow rate per minute.
If the flow rate is greater than 9 litres it is worth considering upgrading your showerhead or tapware. For tapware, avoid restricting the flow on bath taps as it will just lengthen the time it takes to fill the bath. There are a range of tap restrictors available with different flow rates for laundry, kitchen and bathroom sinks.
