Chasing copper into wall for concealed shower mixer

[adcworks]

Hi guys,

I have spent a good deal of time googling and reading forum posts on the question of how to install concealed copper pipework for a concealed shower mixer into concrete walls.

The answers vary so wildly that I am none the wiser. I've seen suggestions to run the copper through flexi conduit or solid plastic pipes. I've seen pvc coated copper pipes suggested. I've seen denso wrapped and foil wrapped copper suggested. And i've seen "no the water regs. do not allow it" suggested.

I am adamant that I do not want to dot and dab board up. Nor do I want to box in. I would like a concealed mixer installed in the concrete wall.

Am I permitted to do this for 15mm copper cold and hot pipes as per water regulations?

What do I need to do to get this done how I want but also within the water regulations.

And finally the cavity will be plastered in afterwards, or should i use some kind of foam first?

Thanks so much would like to start in 2 days

 

[ChrisR]

The water regs don't say much - only what you've read.
So it's up to you.
Everyone has to tile over them, despite any reg.
I like foam for the fill, it has many plus points, unless your tiles are small compared to the hole they're covering.

 

[plummerman]

your pipwork has got to be protected from the concrete. it eats it up

An your pipework must be allowed to expand and contract or joints/fittings can crack other than that you can do as you please.

Personally i place hessian pipe laggin in the chase, place pipe in an clip back then foam over the top, cut it flush once it's gone off and bobs your uncle

 

[adcworks]

so are you guys saying not to plaster over the cavity once the pipes are in? you guys just foam it up, cut flush and tile directly over? does that not leave a waterproofing problem around the edges of the plaster that comes to the cavity edge?

i am still unclear on actual material to put over copper pipes. i could find nothing on hessian lagging. what do you think about this stuff?

http://www.screwfix.com/prods/21356...m;jsessionid=3FV4PJ2LN55E0CSTHZOCFFQ?ts=77767

 

[adcworks]

so my electrician is working in the bathroom today, really nice guy, seems to know his stuff. so i asked him about the shower mixer. he said he knows quite a few plumbers and they all just put the copper piping in the cavity and if anything just to be sure they use denso but not often. then just plaster over the top.

if it's good enough for plumbers, should i be worrying so much about what to cover these bloody pipes with!?

 

[petetheleak]

Run the pipes in plastic , then again you have the potential with leaks if using compression fittings. Do as others have said, Denso is fine . If tiles are sealed / grouted there will be no problem with leaks .It only takes a min to rattle in some foam and once trimmed gives a nice level tiling surface. Stops any rattling of pipes as well.