Plastering around microbore CH pipe

[Lobster]

I've just had a plumber connect up a couple of new radiators today (yeah, I know; but I run out of time) using 10mm microbore.

After some discussion, as it's an essentially solid floor, he's ended up running the microbore concealed behind the skirting, and the flow and return emerge from the wall just above the skirting from what is now a 1" square hole in the plaster (the wall structure is solid brick with internal sand-cement plaster).

My question is, what would be the best way of filling these holes back to a flush surface, so that the surface doesn't crack when the pipes get hot? The wall is currently freshly skimmed and will be emulsioned when the plumbing etc is done.

Thanks

[Lobster]

On 31 Oct 2014, "Phil L" grunted:

Thanks for that.

It's probably a generous inch, TBH...! Thinking further on this, maybe the answer is to wrap a slack collar of some sort around the pipe; fill around that with conventional plaster/polyfilla etc; and then when dry remove the collar and fill the remaining hole with caulk. Otherwise am a bit worried with getting the larger area flat enough to look OK?

[Tim Watts]

Yes - that's what I'd do. You need a bit of sheet foam, 3-4mm thick - like the stuff used to pack electronics for shipping.

4" filler blade should do it - flatness that is...

Personally I would leave the foam around the pipe.

[stuart noble]

Good thinking Tim! Removing the collar would be the worst part and isn't necessary. Those foam camping mats that turn up in the Pound Shops now and then are ideal for this sort of thing

[Lobster]

On 02 Nov 2014, stuart noble grunted:

Thanks guys - will report back how well it works in due course!

[Lobster]

On 03 Nov 2014, Lobster grunted:

Well... having now fitted the skirtings, unfortunately this isn't going to work. I found some of the sheet foam, which would have been perfect for the job if the pipes simply emerged from the wall more-or-less at right angles; however they don't; the angle is relatively shallow and then they travel away from the rads at an angle, only just below the surface of the wall, until they vanish below the top of the skirting.

Without replumbing, the only solution is going to be to cover it all in caulk. Hey ho.

[Tim Watts]

Photos?