How much salt would I need to float in my bath? © Getty Images

How long does a shower have to be, to use the same amount of water as a bath?

Many believe that showering uses less water than filling up a bathtub, but that all depends on how long you shower for!

Asked by: Lawrence Berry, by email

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A bath filled about a third of the way up (which takes the water level over your belly button when you lie down) requires around 75 litres. An ordinary electrically heated shower puts out four litres per minute. So a 19-minute shower is just more than a bath. If you have a power shower, flow rates could be doubled and you’d need just 10 minutes.

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