Outside our house water feed

[Rudie]

Hi all

Wanting to get a cold supply of water to rear of garden that’s about 20m away. I have a down stairs shower room where I’m hoping I can tap into the cold water supply and feed outside with a iso valve maybe on the inside in case I need to cut off the water but was looking at the thermal type feed that are lie a hose pipe to feed outside? It will be buried in trunking underground maybe a few inches and covered in a combo of slabs and gravel.

So my questions are is this feasible? And will the pipe be safe over winter and will the pressure be ok if I tapped out of the toilet feed or shower feed?

Thanks in advance.

 

[Madrab]

Any buried pipe really needs to be far enough down to avoid mechanical and freezing damage. Mains water pipe is typically buried at least 750mm deep for that reason. Probably wouldn't need to be that far down if it's well insulated but I would recommend it's placed a fair amount more than a couple of inches.

Pressure and flow at the outlet will be dictated by the available mains pressure and flow.

 

[oldbuffer]

As Madrab, plus:
1. If your downstairs shower WC are tank fed rather than mains fed, you may be disappointed with the outside tap's flow rate.
2. An outside tap requires the following to be fitted within the thermal envelope of the property:
2.1 An isolation valve.
2.2 A double check valve.
2.3 A drain off point.
3. Fitting an outside tap with a built in check valve is not permitted for new installations.

 

[Rudie]

thanks guys. got a double check valve ready to connect to one of the existing pipes.
the water is mains fed not tank fed.
the second iso valve you specify above - whats that one for if i already have a double check valve?

 

[Madrab]

A double check valves stop backflow, an ISO valve is to isolate the supply, there is only one ISO valve referenced - 2.1?

 

[Rudie]

Ah yes sorry get you now. I wrongly assumed the double check valve had an iso in there.

Internally what would I fit first from the main, the double check valve and the iso before it goes external?

 

[Madrab]

ISO - Double check - drain off - if this is for an outside tap and the pipe is rising.

If the pipe isn't rising then no point for a drain off. If that's the case then isolate and drain off at the outlet, or at least leave it open. This is just in winter or course to avoid the above ground pipe freezing