Hi, I've got a leaking / not working internal stop cock which I need to replace. The pipework between the internal stop cock and the street stop cock is lead and I don't fancy digging a trench etc and paying Thames Water to connect new plastic pipework. The pipework from the internal stop cock internally is copper.

Can I cut the old lead pipe close to the stop cock and connect one of these lead to MDPE couplers? http://www.toolstation.com/shop/p74879 Then connect 25mm pipe through the sub floor void in the hallway and then below the new screed that will be put down in the kitchen and then connect a new internal stop cock in the kitchen?

Also, does the MDPE in the floor void need to be lagged / insulated / boxed in something?And how should I run the MDPE under the screed - in the insulation or chase out the screed afterwards?

Thanks in advance.

You need a lead loc.
The plumbers merchant will know what you mean.
You may also need to file down the lead pipe to get
it to fit into it as lead varies quite a bit.
They come in different sizes and will allow you to connect straight
onto a 15 or 22mm copper pipe. From there you can connect a stop valve.

This may be a stupid question but what's the difference between a lead loc and the lead to mdpe coupler in the link?
Also why would you go for copper rather than MDPE?
There's quite a long run (around 9m) from where the current stopcock is in the hallway (under the floor) to where I want to put it in the kitchen.
Should I keep it where it is even though it's not accessible unless I pick up the flooring or move it to the kitchen?

Thanks

Pipe under floor has to be insulated.

You cannot bury mains pipe in concrete. It has to be accessible but a flexible pipe can be fitted in a tube duct so it can be pulled out.

Tony

What do you recommend insulating it with? Would this be suitable or should I be looking for something else?

http://www.ebay.co.uk/itm/28mm-Pipe-Insulation-Armaflex-32mm-Thick-x-2m-Pipe-L440-/200579244310?pt=UK_Home_Garden_Hearing_Cooling_Air&hash=item2eb3746116#ht_2754wt_698

Thanks

Philmac universal coupler is the best fitting for what you want.

Get a Real Plumber in & he'll wipe a lead ball joint on it in minutes.......................

As the answers above indicate, manipulating, or even working with in-situ lead service pipe is nowadays a contentious issue.
Some Utilities will insist that the lead is replaced if their attention is drawn to it or before they will make any connections at the external stop-tap.

AAMOI: when i was young, i was taught to use "Bobbins" to bend thin wall 3" and 4" closet bends - a waste of time, i never had occasion to use. Lead wiping is going the same way.