3m run 10mm Microbore flow restrctn guesstimate / wisdom

[gsportgeorge]

Hi,

I plan on running a hot and cold supply to a very small hand basin and toilet cistern (no hot to the toilet mind) and the only neat short way to do it involves about 3m burried in a wall with two 90 degree bends in it.

There has been an old lead pipe doing this job for the last hundred years or so but hasnt been working in my time in the house.

My plan was to run 10mm microbore copper in a suitable pipe conduit (lime)plastered into the wall for some of its run and behind tiles and tileboard for the rest (where is passes through main bathroom).


Will 3m of 10mm microbore kill the flow to a ridiculous degree?

Is this plan even OK? I can always claim that the pipe is a replacement for the lead rather than a "new" installation if it makes a difference.

Thanks

George

 

[gas4you]

It is my understanding that all hot & cold pipes have to be accessible for inspection when chased or buried in walls and screed etc.

So this would probably mean they have to be in a duct.

If you have a gravity HW system, then this will not work satisfactorily anyway.

You would need good mains pressure to get a good flow out of microbore.

 

[gsportgeorge]

Sorry, should have said, it is being fed off a combi so mains pressure.

I have done a fair bit of searching and the point about being "withdrawn for inspection" keeps coming up, but this is virtually impossible without building enormous access panels. How is a duct distinguished from conduit?

 

[gas4you]

To me the duct would have to be able to be opened its full length for inspection.

I am only a gas heating engineer, so I am not up on the finer points of water regulations.

 

[blondini]

I did a much longer run in 10mm plastic and it was goooooood.
//www.diynot.com/forums/viewtopic.php?p=1008151#1008151

 

[cowboyplumber]

done this before. worked fine.

 

[gsportgeorge]

Thanks that sounds reasonable. I am putting isolation valves on both lines below this section where they are easily accessible, and if the pipe ever leaks I am happy to break back into the chased section of wall to fix or replace, (or at least happier than I would be trying to explain to my wife why there have to be two exposed pipes running accross the wall on the stairs...)

George