These are the required pipe distance measurements for installing light or heavy duty water meters to meet installation standards.
Find out more about how to install a meter correctly from our Water meter installation guide.
20 mm to 50 mm light duty meters
You need to measure between the ends of the threads to work out the distance needed to allow for these light duty meters. The arrows on the image show where to start and finish measuring.
Once you've done this, use the measurements below to work out your distance.
You need to allow a minimum of 300 mm clearance around light duty meters. This helps us to safely read, maintain and exchange them in the future.
The arrows show where to start and finish measuring.
* This doesn't include the distance for the backflow prevention device.
The right-angle stop valve and the elbow for the recycled water meters below have female BSP threads.
| Meter size (DN) – recycled water | Distance to allow – recycled water |
|---|---|
20 mm | 270 mm |
25 mm | 265 mm |
The bridging piece
When you have your distance right, you need to insert a bridging piece where the meter will go. We'll remove the bridging piece when we install the meter.
If everything is done correctly, we won't have any problems installing a meter later on.
The bridging piece.
A correctly installed meter.
50 mm to 300 mm heavy duty meters
To work out the distance required for heavy duty meters, measure between the flange ends. Flange ends have flat surfaces instead of threaded ones.
Heavy duty meters have extra parts. These must also be allowed for.
Use the measurements below to work out your distance. Allow a minimum of 500 mm clearance around the meters so we can exchange them in future.
| Meter size | Gate valve | Dirt box | Distance piece inlet | Meter | Distance piece outlet | Meter assembly space |
|---|---|---|---|---|---|---|
50 mm heavy duty | 175 mm | 208 mm | 372 mm | 311 mm | 150 mm | 1,216 mm |
80 mm | 203 mm | 252 mm | 396 mm | 413 mm | 240 mm | 1,504 mm |
100 mm | 229 mm | 260 mm | 476 mm | 483 mm | 300 mm | 1,748 mm |
150 mm | 267 mm | 406 mm | 762 mm | 500 mm | 450 mm | 2,385 mm |
200 mm | 292 mm | 428 mm | 1,000 mm | 520 mm | 600 mm | 2,840 mm |
250 mm | 330 mm | 522 mm | 1,250 mm | 450 mm | 750 mm | 3,302 mm |
300 mm | 356 mm | 580 mm | 1,500 mm | 500 mm | 900 mm | 3,836 mm |