fitting a check valve to a 25mm MDPE outside supply spur

[AJ16]

I've want to take a spur off the short section of 25mm MDPE pipe going into the house just just after the stop tap. It's to get full pressure for the outside taps otherwise the 15mm pipes snake all the way through the house to the outside tap. The question is what should be done to comply with regs and avoid any possible siphoning back into the supply? Is is permissible to fit an inline check valve into the spur line before it reaches the taps? Mains pressure is 6Bar.
Thanks

 

[Ermintrude]

stopcock then drain off then tee. On branch ISo double check drain off. Assuming it's just for a tap?

 

[AJ16]

stopcock then drain off then tee. On branch ISo double check drain off. Assuming it's just for a tap?

Yes it's for a couple of outside taps. The MDPE pipe would run about 20metres to the first tap which is 900mm above ground level, then another 30metres down the garden to the second tap. The second tap has a drain valve in the feed pipe as it's at a lower levee because the garden slopes down.

Where in the branch should the check valve/isolating valve be fitted? I'm guessing that the DCV should be close to the start of the branch and with it's own stop tap first (for winter), then maybe a check valve afterwards or maybe just in each tap?
cheers

 

[AWheating]

Tee the mdpe together and fit double checks as the new runs come out of the ground. External lag everything above 750mm below ground level. Any valves fitted must be accessible for use and maintenance

 

[AWheating]

Also if you have an internal water meter you will need to get the new taps metered.

 

[AJ16]

All understood, many thanks