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Water Meter Reading – Calculator


Water Meter Reading, how?

An increasing number of people have water meters at their property nowadays in the UK, especially on new houses, but how do you take a water meter reading and what do the numbers on a meter mean?

Here we guide you through a typical water meter….

Water Meter Reading
Water Meter Reading

Water Meter Reading – numbers?

The numbers in the diagram below are from a made up water meter reading. But what do the numbers mean? First of all, meters may vary but this is for a typical UK water meter with five black numbers and three red numbers, then a dial numbered 0 to 9 and a small cog. All mean different things!

Water Meter Reading - how to read
Water Meter Reading – numbers meaning

A simple place to start with a water meter reading is the right hand most black number. Each digit is one meter cubed (imagine a cube one meter high, wide and deep). It does not sound much but that is 1,000 litres of water!

Remember 1 litre of water is 1kg so 1,000 litres 1,000kg or one tonne.

The second most simple number on a water meter reading are the red numbers. The right hand most number on that (there are usually three) is one litre. We discuss this more on our quick guide on how to read a water meter, which is related to this longer guide.

So combine these two, and it is fairly simple to see that the water meter reading in the diagram above is for 323,501 litres of use – or about one-eight of an Olympic sized swimming pool which is 2.5million litres. Interesting fact…

How long would it take to fill an Olympic sized pool?…

Here are the steps to calculate that…

  • Step 1 – Regular tap pressure in the UK would be about 12.5 litres per minute
  • Step 2 – So that is 200,000 minutes to fill the pool
  • Step 3 – Which is 3,333 hours
  • Step 4 – That is 139 days to fill an Olympic swimming pool with a tap
  • Step 5 – Roughly speaking that is £3,500 of water on a meter reading!

We have a page dedicated to swimming pool leak detection and if you want to know how much water your swimming pool holds, look at our water volume calculator. We also have a really useful article on Water Flow Meters (compared to water pressure gauges).

Water Meter Calculator

In order to calculate how much water you are using in a given time using your water meter readings, here is what you need to do…

  • Take a reading of your water meter using the guide above
  • Take a note of the number of litres it was at
  • Leave your meter for a set period of time such as a day or a week
  • Look at what the new number is on the water meter reading
  • Subtract the first number from the second number
  • This will show how many litres you have used in that period of time

What is normal water usage in the UK?

An average UK home uses in the region of 140 to 150 litres per day.

But this may vary according to the number of people in the house.

How much water is used to flush the toilet?

  • Flush the toilet? – an average toilet flush is about 8-10 litres
  • Have a shower? – an average shower is about 100-150 litres
  • Have a bath? – an average bath uses about 80-100 litres
  • Using the Washing Machine? – a washing machine uses 50 litres per wash
  • Using the Dish Washer? – a dish washer uses about 10 litres per clean
  • Washing your Hands? – uses on average 5 – 10 litres per hand wash
  • Cleaning your Teeth? – uses on average 10-15 litres of water

We have a variety of other tools to help understand water leaks too.

Water Leak Detection Service
Water Leak Detection Service

So an important question is clearly?

Will my Water Meter show a leak?

The answer to this might surprise you, basically yes it could help to show you have a leak at your home. How? – assuming all your devices are off in the property (dishwasher, washing machine etc) and nobody is running a tap or visiting the toilet, if your water meter is running, you may have a toilet water leak. Use the guide at the top of this page to see how much water you are losing and the speed you are doing so.

For example, if in 10 minutes your right-hand most red number moves on 2 digits, that is 2 litres of water. That might not sound like much but it would be 12 litres an hour or 288 litres a day. Enough water used to have a few baths.

So clearly you can see the scale of the leak. Generally, the bigger the leak the more potential for damage you have, the greater the possible cost (directly and indirectly) and it can increase the chances of finding it. If you are wondering about a leak on a boiler or central heating system, you may find our Boiler Pressure Leak Calculator handy.

The last thing to say is that, often, water leaks are fairly small drips or trickles but even they can cause a lot of problems over time. Of course although a water meter might help highlight you have a water leak, it will not tell you where it is.

Our pages on finding water leaks and calculating the cost of water from a leak are useful to check out if you have worked out the size of your leak.

If you need a professional leak detection specialist, get in touch with us.

Whilst on the subject of water leaks and water meters, our guide to who is responsible for a leak outside a house is a useful read too. We also have an interesting guide to pure water and how we use it in some of our tests. Finally, on a similar theme a very informative guide to UK Water Test Kit Strips and how they work, and a related guide to Drinking Water Test UK.

We mention water meters in our UK water usage calculator too.

What are the units on a water meter?

Water Meter Reading

In the UK our water meters (whether digital or analogue) most often show cubic meters of water usage at a property, usually the black numbers on a meter. Each cubic metre (M³) is made up of 1,000 litres which are the red numbers to the right of the water meter dial. The other readings are normally fractions of those amount to track small levels of water usage, which is useful when measuring water leaks.

Is it worth going on a water meter?

Water Meter Reading

Switching to a metered water service, with a water meter could be beneficial, especially if you are someone who is a low water usage person. It is most likely worthwhile doing some estimates yourself based on your local water company in the UK. It might be worth looking at what information they provide, either online or by contacting them.