Proper way to connect a 15mm pipe to a shower body - all buried in a wall

[richards1978]

Hi everyone,

Short version:
How should 15mm copper pipe runs be connected to a 1/2 bsp port on a concealed/buried shower body?

Long version:
When removing the old tiles from our bathroom with the plan to give everything a refresh with some new tiles, I managed to uncover the buried pipework for the (concealed) shower mixer body.

This isn't a problem, as I was expecting this and was going to retank everything and tile over it. However the piepwork ow just buried in the wall and covered in plaster without any sleeving, and then connects to the shower mixer body with a 15mm compression fitting (bes 6685 - I looked it up).

Thanks

I'm sure I've heard that pipes shouldn't be buried unprotected directly in plaster and that compression fittings should never be buried and made inaccessible, but wanted to see what people's views are on this while I have everything open and accessible, and before I bury it all again.

 

[Wayners]

Some prefer surface mounted showers mixer and pipes now because of problems.
Other way is to install access panels.
Some have access from room wall behind.
Access is something you should consider

 

[Madrab]

We always wrapped copper when it was to be imbedded in concrete or plaster but then found out it wasn't required and it seems (edit) it may be a bit of an urban myth

This is more about concrete but includes plaster in it's comments - https://blog.copper.org/water-servi...er-tube-in-concrete-and-plumbing-applications

 

[denso13]

The pipes are fine, but you'd normally have space around the valve/connections which is covered by the shower valve wall plate.

 

[steven lee]

Madrab is spot on, we always taped or sleeved copper going into plaster. Apart from corrosion it also lets the pipe move a touch when it heats and cools. For the 1/2 inch ports I would use 15mm x 1/2 female irons soldered on, not compression, because a buried compression fitting you can never get at again is asking for trouble. If you can manage it, leave the mixer connections behind a removable panel instead of burying them solid.

 

[MeldrewsMate]

I have seen iron pipework rotted to bits in damp plastered walls, haven't met a similarly affected copper pipe yet, however the advice around allowing movement is worth listening to. PVC tape is good for chemical protection, two or three loose wraps accommodates some movement.

 

[richards1978]

Thanks - that was my worry on the compression fittings. The shower unit is chased into a wall, so access will be

Really good advice on the wrapping too. I didn't think about how the wrapping also allows the pipe to move slightly as it expands.