On Wed, 31 Mar 2021 14:08:29 +0100, Tim Lamb
wrote:

In message , Andrew
writes
On 30/03/2021 12:34, The Natural Philosopher wrote:
On 30/03/2021 09:44, Mike Halmarack wrote:
On Tue, 30 Mar 2021 08:54:41 +0100, Tim Lamb
wrote:

In message , The Natural Philosopher
writes
On 29/03/2021 21:16, Tim Lamb wrote:
In message , Mike
Halmarack* writes
On Mon, 29 Mar 2021 17:04:07 +0100, Andrew
wrote:

On 29/03/2021 16:56, Mike Halmarack wrote:
Same old problem. Rising main to upstairs flat running through my
airing cuboard. Bits of blue pipe, bits of black, with
couplers, all
hanging loose, unbracketed.
Management company's plumber says it's fine but it keeps
leaking from
different joints.

Though the whole rising main running through the three flats
should be
replaced it very likely won't be.

So my question is: if I cut out the whole run through my airing
cupoard leaving a stub coming up through the floor and one
poking out
of the ceiling, then put a single length of pipe between the two
is there a better quality joining method, more effective than the
standard couplers to complete the job?
Maybe something resembling heavy duty heatshrink or the like?


You could try that but not reconnect the ends and then wait for
someone to come along and fix it. :-)

Remind us what you would be cutting - original (?imperial) copper,
black PVC or something else. I don't think you can easily join
black PVC to blue MDPE, especially with those nasty hand-tightened
compression fittings that are used on MDPE these days.

Sometimes I'm a bit excessive on the details so I have to try to keep
it brief. I was hoping that blue and black with couplers woud be
enough clues.
As it is, the two stubs would be black, so with black between, the
match might a better one than the current.
* Have a look at *Johnson couplings*. The *black* pipe may be 1/2"
alkathene.


rising main is at least 22m and more commonly bigger

MDPE

Black of an unknown age. 1960's mains piping commonly 1/2", 3/4" 1.0"
bores.

I must get that vernier gauge from Lidl. Hope they've still got one.

Well, yes, but to this level of accuracy, what's wrong with e.g. a
screw clamp applied, then removed and measured with a tape measure?
IIRC most rising mains today are 25mm blue MDPE - and the couplers
for that work very well.


He is living in a block of flats built in the 1960's. That stuff
didn't exist then. Keep up.

Has he said that? I guessed '60's because I knew black imperial sized
alkathene was in use then.

Early 70's really, if that would make much difference.
--

Mike