joining blue alkathene

[johnnyisajoiner]

Hi All members,
I have been asked recently to remodel a customers kitchen which involves knocking out an external wall to put in bi-fold doors. However on the wall side where the doors need to go the blue alkathene comes up through the concrete floor right in the centre of the proposed door opening, and joins to 15mm copper into stop tap under existing sink. I am needing advice on digging up the pipe from the concrete floor, joining with a coupling to a suitable pipe that will need to be reburied in concrete/cement based filling so I can relocate stop tap in sink unit in new proposed position. I await your replies.
Many thanks
Johnny

 

[AWheating]

you need to move it from outside, dig and find pipe and relocate. I would not advise running the pipe in a screed.

 

[johnnyisajoiner]

you need to move it from outside, dig and find pipe and relocate. I would not advise running the pipe in a screed.

The alkathene runs from the front of the house (water meter and stop tap) under front garden and then right under the house from front to back under a solid floor and emerges through kitchen floor screed. Do you mean it would be better if I found the pipe in front garden joined it there and then re-routed it around the side of the house to the wall I need it on and then into the house?
This would involve lifting the flags around the side of the house to dig a new pipe in. What would be best to insulate the section of alkathene above ground level where it leaves the ground and up to above DPM level to house entry? It is turning into a bigger job than they expected but if thats what they want, I guess its gotta happen that way unless there is an easier method.

 

[stevetheplumber]

id just go to 22mm copper or hep and sleeve it in floor in an ideal world there shouldnt be a join in the screed but we all live in the real world
any half decent mercants will have the right fittings not having seen it i cant say for sure but you may already have the fittings on the pipe which you could reuse

 

[johnnyisajoiner]

stevetheplumber, what would you sleeve it with would the 9mm walled insulation sleeving do it or would it be better in plastic pipe sleeving?

 

[sparky]

Blue alkathene? Was this used before blue MDPE?

 

[GQuigley67]

I would sleeve it in plastic pipe, and seal from one end that way if you have a leak it will show

 

[johnnyisajoiner]

Blue alkathene? Was this used before blue MDPE?

Not sure, it may well be called MDPE but I always knew it as alkathene from way back and just call it that now, the pipe I was referring to is approx 10 years old so it may be Medium density polyethylene as opposed to alkathene.

 

[AWheating]

it should not be run under the house, how do you know it does?

 

[johnnyisajoiner]

it should not be run under the house, how do you know it does?

Just a bit of digging revealed it dissappearing under the house. It is in a direct line from the stopcock on the street to the kitchen at the rear of the house where it pops up again 6" inside the inner wall under the sink unit. It is a persimmon of yorkshire built house renowned for their short cuts and dodgy work.