Garden Tap from washing machine valve ?

[jitasb]

Hello.


I am looking to install an outside tap.
It will be fixed to external house wall above a drain and the best access to cold water water supply is thru the wall to the utility area where I have a sink and a washing machine.


The pipe work under the sink is a bit restricted and not very long and there doesn't seem to be much give in it. So I am now unsure of my original approach to cut the pipe and install a copper Tee fitting. Not having done soldering before I was going to install a compression Tee and then take pipe out from there to the wall then thru the wall to the garden tap.
But I don;t want to cut out a section then find that I can't squeeze in the tee-fitting and my water supply to the sink and washing machine would be buggered. So I have some questions please which I hope some experienced people might be able to answer.


1. What is the approach if there is very little give in the pipe to fit a Tee-fitting ? Is there a way to cut out a larger section then somehow 'rebuild' it. I guess the same question is if you have cut out a section which is too big...how do you 'repair' it ?


2. In the same area, there is an existing elbow in the pipework for the washing machine. This has the standard washing machine valve (15mm) fitting with blue handle. The washing machine standard hose connects to this valve.
I was wondering if this could be used with a Y-splitter of some kind so using the same valve to feed both the washing machine and some new pipework leading to the garden tap. The new pipework to the garden tap would have its own isolation valve and check valve so the water would be separate.


Would the downside be the water pressure ? As i presume that the washing machine valve reduces the water from the standard 15mm ...I think I read it reduces it to 5 or 6mm ? So that might not be enough for garden tap needed for hose , washing car , pressure wash etc ?
But also, fitting the required isolation valve and check valve to new pipework ...does this not also reduce the water pressure from the initial 15mm ??


3. Is copper still the best way to go with regards to pipework and valves etc ? I see that that Hep20 seems be getting some good reviews ?


Many Thanks.

 

[Howsie]

Sorry I can't post more from my phone but doesn't forget to sleeve the pipe though the wall and fit a double check valve.

 

[Best]

The washing machine valve is no use for supplying a tap. You might be best getting a plumber in as they know all the tricks to do it right and to regs.
But if want to try it, you could consider using a 15mm brass tee in place of the washing machine valve (if that is suitable) and go from there. One end will do for to the washing machine valve and the other to the new tap.
You need a 15mm full flow isolator valve, tap, 15mm double check valve.
Also need an outside tap flange or other means of linking tap.
You could use push fit fittings inside, but I would use copper pipe plus brass (or soldered) fittings.)
DO NOT buy those nasty DIY tap kits that come with a hose and self cutting valves!

 

[Riley]

I didn't think you could fit those double check valve taps mate as they can be removed leaving no check valve in situ

 

[Best]

I didn't think you could fit those double check valve taps mate as they can be removed leaving no check valve in situ

Tbh I know you are supposed to fit a double check valve anyway, but no idea if tap can be just ordinary non check valve type.
I will add that to the post. Used to be the building inspectors looked for the little nut below the tap to confirm it had the check valves. They fail anyway.

 

[Howsie]

CV belongs inside to protect from the weather.

 

[jitasb]

The washing machine valve is no use for supplying a tap. You might be best getting a plumber in as they know all the tricks to do it right and to regs.
But if want to try it, you could consider using a 15mm brass tee in place of the washing machine valve (if that is suitable) and go from there. One end will do for to the washing machine valve and the other to the new tap.
You need a 15mm full flow isolator valve, tap, 15mm double check valve.
Also need an outside tap flange or other means of linking tap.
You could use push fit fittings inside, but I would use copper pipe plus brass (or soldered) fittings.)
DO NOT buy those nasty DIY tap kits that come with a hose and self cutting valves!

Ahh thanks.
yes..I could use a Tee-fitting in place of the washing machine valve. Then re-use the valve from one output and set up new pipework for the garden tap from other output.

 

[jitasb]

Tbh I know you are supposed to fit a double check valve anyway, but no idea if tap can be just ordinary non check valve type.
I will add that to the post. Used to be the building inspectors looked for the little nut below the tap to confirm it had the check valves. They fail anyway.

From what I have read about it recently. The double check valve has to be inside. So the outside tap has no requirement to have a check valve in it. I presume this is because they can fail outside due to frost etc, but are ok inside.

 

[Spanner2k7]

From what I have read about it recently. The double check valve has to be inside. So the outside tap has no requirement to have a check valve in it. I presume this is because they can fail outside due to frost etc, but are ok inside.

This is correct, the only time you can fit a outside tap with a check is you are doing a direct replacement.
As to the original post, as you has lack of pipe work to cut into, and you are going to use compression, I would remove the washing machine tap and work from there. You could put a compression tee where the washing machine tap was. And if you don't mind a chrome nut on a brass fitting use existing nut and Oliver.