Measure the distance

If you're a plumber and are installing a meter, the distance you need to allow between the pipes depends on the size of the meter.
 

To work out the distance you need to allow for these meters, measure between the ends of the threads.

Pipes without a bridging piece

This is where you start and finish measuring.

Then use these measurements to work out your distance.  
 
Meter size - DN Distance to allow
Drinking water Drinking water
20 mm 260 mm
25 mm 310 mm
32 mm 350 mm *
40 mm 350 mm *
50 mm light 340 mm *
The right angle stop valve and elbow have male BSP threads.  * This doesn't include the distance for the backflow prevention device.
Recycled water Recycled water
20 mm 270 mm
25 mm 265 mm
The right angle stop valve has a female BSP thread. The elbow has a female BSP thread.

We need you to allow a minimum of 300 mm clearance around these meters. This helps us safely read, maintain and exchange them in the future.

When you've got your distance right, you need to insert a bridging piece where the meter will go. It should look like this.

Pipes with a bridging piece

We take the bridging piece away when we install the meter.


When you do this correctly, we won't have any problems installing a meter later on. This is what it will look like.

Pipes with a meter

We can't install meters when the pipes aren't the right distance apart.

To work out the distance you need for these meters, you measure between the flange ends. These ends have flat surfaces instead of threaded ones.

Heavy duty meter diagram

These meters have extra parts - you need to allow distance for these too.


Then use these measurements to work out your distance.

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 


We need you to allow a minimum of 500 mm clearance around these meters too. This is so we can exchange them in future.

Pipes with a meter

We can install a meter when the pipes are the right distance apart.