Filling over radiator pipes for tiling help please

[Prbmoran]

I have had the poly plumbing pipes from the radiator chased into the wall. For this to be done a slim channel has been cut out of the wall. I need to tile over this now- what is my best bet to fill over this hole and pipes? The channel is very narrow and i dont want to cut out the plaster and replace it all. I am worried that if I tile straight over the gap my tile adhesive will affect the pipes if it touches them? Or if i just fill the hole with foam or lightweight filler can it touch the pipes or will it damage them if they expand with the heat? Any ideas or suggestions greatly appreciated. Thanks

 

[Qwerty]

If you can try and wrap the pipe in the foil type wrap around insulation, then tile over as usual. Make sure that there is enough room for expansion (hardly any to be fair).

Any photos?

 

[PaulSmith]

What about pvc channel then a little bonding plaster or thin slither of plasterboard.